日韩美女激情,福利视频免费观看,欧美麻豆久久久久久中文 http://www.hnanf.cn/en/category/blogs/ Thu, 21 Aug 2025 09:51:42 +0000 en-US hourly 1 https://wordpress.org/?v=6.8.3 http://www.hnanf.cn/wp-content/uploads/2024/04/cropped-logo-32x32.png Blog Archive - SANDI TECHNOLOGY CO. http://www.hnanf.cn/en/category/blogs/ 32 32 How 3D printing can solve the problem of high casting scrap rate: revolutionize casting process, improve quality and efficiency http://www.hnanf.cn/en/blogs/how-3d-printing-solves-the-problem-of-high-scrap-rates-in-casting/ Thu, 21 Aug 2025 09:48:39 +0000 http://www.hnanf.cn/?p=2377 Castings scrap rate remains high? In this paper, an in-depth analysis of industrial 3D printing through the moldless, one-piece molding and digital simulation, from the source to eliminate porosity, shrinkage and other defects, and comprehensively improve the casting quality and production efficiency.

3D打印如何解決鑄造高報廢率問題:革新鑄造工藝,提升品質與效率最先出現在三帝科技股份有限公司

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As the cornerstone of industrial manufacturing, the foundry industry has long faced a number of deep-rooted challenges. Among them, high scrap rates are a "hidden cost" that not only means direct waste of raw materials, but also leads to long product development cycles, high rework costs, and the loss of valuable market opportunities. For some complex structure, high technical requirements of the castings, the yield of the traditional process will drop dramatically. This predicament has prompted the industry to urgently seek a technological change that addresses the root causes of the problem. In this context, additive manufacturing (commonly known as 3D printing) with its unique advantages for the traditional casting industry to provide a subversive whole chain digital solutions for the transformation and upgrading of the industry provides a new path.

Chapter 1: Deep Dive: The Root Challenge of Traditional Casting Defects

1.1 Common casting defects and their deep causes

Casting defects are the direct cause of high scrap rates. These defects are not accidental, but are dictated by the physical and process limitations inherent in conventional casting processes.

firstlystomatogether withshrinkage. Porosity mainly originates from the involvement or inability to effectively discharge gases (e.g. hydrogen, mold outgassing) in the liquid metal during the pouring and solidification process. When the dissolved gases in the liquid metal are released due to reduced solubility during cooling and solidification, bubbles will form inside or on the surface of the casting if they are not discharged in time. Related to this is shrinkage, which is a natural phenomenon of volume contraction of the metal during solidification. If the cooling system is not properly designed, resulting in local mold temperature is too high, or insufficient complementary shrinkage, it will form internal voids or depressions, the so-called shrinkage holes.

Next.sandwichedtogether witherror type (math.). In conventional sand casting, sand molds and sand cores usually need to be assembled and bonded after being made from multiple pieces separately. In this process, any tiny rupture of the sand core or improper bonding may lead to sand particles being caught in the metal liquid, forming sand entrapment defects. In addition, if the mold parting surface or the sand core is not positioned accurately, it may also lead to the casting of the upper and lower parts of the misalignment of the mis-shape defects.

endcold storagetogether withcrackles. When the fluidity of the metal liquid is poor, the pouring temperature is too low, or the runner design is narrow, the two metal streams are solidified without being fully integrated at the leading edge, leaving a weakly connected cold segregation. And during cooling and solidification, if there are uneven stresses within the casting, thermal cracks may occur during shrinkage.

1.2 The traditional mold manufacturing "high cost" and "low efficiency" dilemma

Another core pain point of the traditional casting process is its mold manufacturing process. Traditional wood or metal core box manufacturing is a labor-intensive, highly skilled worker-dependent process with long lead times and significant costs. Any minor design change means that the mold needs to be rebuilt, resulting in high additional costs and weeks or even months of waiting time.

This over-reliance on physical molds also fundamentally limits the design freedom of castings. Traditional mold-making processes are unable to mold complex internal runners and hollow structures in one piece, which must be disassembled into multiple independent sand cores and then assembled by complex tooling and labor. 2. This process limitation forces designers to compromise and sacrifice part performance for manufacturability, such as simplifying cooling channels to accommodate drilling processes that do not allow for optimal cooling.

To summarize, the high scrap rate of traditional casting is not an isolated technical problem, but a product of its core processes. The traditional "physical trial and error" mode makes the foundry in the discovery of defects, need to go through a long process of mold modification and retesting, which is a high-risk, inefficient cycle. 3D printing's revolutionary value is that it provides a "moldless" solution, fundamentally reshaping the entire production process, will be the traditional "physical trial and error" mode, will be the traditional "physical trial and error" mode, will be the traditional "physical trial and error" mode, will be the traditional "casting" high scrap rate is not an isolated technical problem, but its core process products. The revolutionary value of 3D printing is that it provides a "moldless" solution that fundamentally reshapes the entire production process, transforming the traditional "physical trial-and-error" model into a "digital simulation validation" that puts the risk in front of the process, thus eliminating most of the causes of scrap at the source.

Chapter 2: 3D Printing: A Revolutionary Breakthrough from Technology to Solution

2.1 Moldless production: eliminating the root causes of obsolescence

The core advantage of 3D printing is its "moldless" production method, which allows it to bypass all of the mold-related challenges inherent in traditional casting, thus radically reducing scrap rates.

Directly from CAD to sand mold. Binder Jetting in Additive Manufacturing is the key to making this happen. It works by precisely spraying liquid binder onto thin layers of powder (e.g. silica sand, ceramic sand) from an industrial-grade printhead based on a 3D CAD digital model. By bonding layer by layer, the 3D model in the digital file is constructed in the form of a solid sand mold or sand core. This process completely eliminates the need to rely on physical molds. Because there is no need for lengthy mold design and manufacturing, the mold-making cycle can be shortened from weeks or even months to hours or days, enabling "print-on-demand" and rapid response to design changes, dramatically reducing up-front investment and trial-and-error costs.

One-piece molding and complex structures. 3D printing's layered manufacturing approach gives unprecedented design freedom. It is able to mold complex sand cores that would traditionally have to be split into multiple parts, such as the meandering runners inside an engine, into a single monolithic piece. Not only does this simplify the casting process, but more importantly, it completely eliminates the need for core assembly, bonding and misalignment, thus eradicating common defects such as sand entrapment, dimensional deviations, and misshaping caused by such issues.

2.2 Optimization process: data to guarantee casting quality

The value of 3D printing goes beyond "moldlessness" itself. It elevates the manufacturing process to a whole new digital dimension, allowing data to be verified and optimized before physical manufacturing, turning "after the fact" into "before the fact".

Digital Simulation and Design. During the digital design phase prior to 3D printing, engineers can use advanced Finite Element Analysis (FEM) software to perform accurate virtual simulations of the pouring, make-up shrinkage and cooling processes. This makes it possible to anticipate and correct potential defects that could lead to porosity, shrinkage or cracks before actual production. For example, by simulating the flow of the liquid metal in the runners, the design of the pouring system can be optimized to ensure smooth filling and effective venting. This digital foresight greatly improves the success rate of the first trial run and guarantees casting yields at the source.

Excellent sand properties. 3D printed sand molds, due to their layer-by-layer construction, can achieve uniform densities and air permeability that are difficult to achieve with traditional processes. This is crucial for the casting process. Uniform gas permeability ensures that gases generated inside the sand mold can escape smoothly during the pouring process, significantly reducing porosity defects caused by poor venting.

Cooling with shape. Conformal cooling technology is another revolutionary application of 3D printing in the field of casting molds. Mold inserts manufactured through metal 3D printing have cooling runners that can be designed to exactly mimic the surface contours of the casting. This achieves fast, uniform cooling, significantly reducing deformation and shrinkage due to uneven shrinkage, thus dramatically reducing the scrap rate. According to data, molds with follow-through cooling can reduce injection cycle times by as much as 70%, while significantly improving product quality.

From "physical trial and error" to "digital foresight". The core contribution of 3D printing is to transform the traditional foundry model of "trial and error" into "anticipatory manufacturing". It enables foundries to perform numerous iterations in a digital environment in a cost-effective manner, which is a fundamental shift in mindset and business process. This "hybrid manufacturing" model makes 3D printing easier to adopt by traditional foundries and enables the most efficient production. For example, 3D printing can be used to create the most complex and error-prone sand cores, and then combined with sand molds made using traditional methods to "build on the strengths".

Chapter 3: SANTI TECHNOLOGY: A Digital Engine to Empower the Foundry Industry

3.1 Core equipment: "hard power" for casting innovation

As a pioneer and leader in the field of additive manufacturing in China, 3DPTEK provides strong "hard power" support for the foundry industry with its self-developed core equipment.

The company's core product lines are3DP Sand Printerthat highlights its leadership in technology. Flagship devices3DPTEK-J4000With an extra-large molding size of 4,000 x 2,000 x 1,000 mm, it is highly competitive on a global scale. This extra-large size allows large, complex castings to be molded in one piece without the need for splicing, further eliminating potential defects caused by splicing. At the same time, for example

3DPTEK-J1600PlusDevices such as these offer high accuracy of ±0.3 mm and efficient printing speeds, ensuring that superior quality is achieved while producing quickly.

In addition, SANTI Technology'sSLS (Selective Laser Sintering) Equipmentseries, such asLaserCore-6000The machines are also excellent in the field of precision casting. This series of equipment is particularly suitable for the manufacture of wax molds for investment casting, providing a more accurate solution for high-end, fine parts in aerospace, medical and other fields.

It is worth mentioning that SANDI Technology is not only an equipment supplier, but also an expert in material and process solutions. The company has developed more than 20 binders and 30 material formulations, compatible with cast iron, cast steel, aluminum, copper, magnesium and other casting alloys. This ensures that its equipment can be seamlessly integrated into a wide range of casting applications, providing customers with comprehensive technical support.

3.2 All-link services: integrated casting solutions

The competitive advantage of SANDI Technology lies not only in its hardware, but also in the integrated solutions it provides along the whole chain. The company has a strong "Trinity" innovation system - "research institute + post-doctoral workstation + R&D team". This model ensures continuous technology iteration and innovation momentum, and its accumulation of more than 320 patents is a strong proof of its technological leadership.

The company offers a "one-stop" turnkey service from design and 3D printing to casting, machining and inspection. This vertically integrated model greatly simplifies the customer's supply chain management, reduces communication costs and risks, and allows the foundry to focus on its core business.

3.3 Classic Case: Data-Driven Proof of Value

Successful cases are the most persuasive tool to convince potential customers. Through a series of real-world projects, SANDY Technology has quantified the significant business value that 3D printing technology brings.

in order toAutomotive water-cooled motor housingAs an example, this case perfectly demonstrates how the 3DP sand casting process solves the one-piece molding problem of "large size, thin wall, complex spiral cooling channels". 21. The successful application of this technology in the field of new energy vehicles has proved its significant advantages in the production of high-performance, complex structure castings.

On the otherIndustrial pump bodyIn the case of SANDI, SANDI adopted the hybrid manufacturing model of "3DP outer mold + SLS inner core". This complementary strategy shortened the production cycle by 80%, and at the same time improved the dimensional accuracy of the castings to CT7 level, which perfectly proved the powerful effect of the hybrid manufacturing mode.

The joint venture project with Xinxin Foundry provides the strongest business argument. By introducing 3D printing technology, the foundry achieved a turnover increase of 1,35%, doubled its profitability, halved its lead time and reduced its costs by 30%. This series of quantitative data provides irrefutable proof of the return on investment of 3D printing technology in the foundry industry.

The following table visualizes how 3D printing can address the pain points of the foundry industry on both a technical and business value level:

Casting defects or pain pointsCauses and limitations of traditional crafts3D Printing Solutions and Value
stomaPoor mold venting; liquid metal entrapped in gasUniform, controlled sand permeability; digital simulation optimizes pouring system
shrinkageUneven cooling; inadequate retractionPredictive optimization by numerical simulation; uniform cooling by shaped cooling channels
Sandwich, Mis-shapeMulti-core assembly, bonding and misalignment; parting face fit errorsOne-piece molding of complex sand cores eliminates assembly; no physical parting surfaces required
High molding costsRequires physical molds, highly skilled labor, long lead timesMold-less production; print directly from CAD files, manufacture on demand
Inefficiency and long lead timesLong mold making; repeated trial and errorReduced cycle time of 80%; rapid iterative design possible; print on demand
Increased business valueLow margins and erratic deliveryTurnover up 1,35%, margins doubled; costs down 30%

Chapter 4: Looking to the future: digitalization and sustainability in the foundry industry

3D printing technology is leading the foundry industry from the traditional "manufacturing" to "smart manufacturing" fundamental transformation. According to the relevant report, the scale of China's additive manufacturing industry continues to grow at a high rate, and in 2022 it will exceed RMB 32 billion. This data clearly shows that digital transformation has become an irreversible industry trend.

In the future, 3D printing will be deeply integrated with artificial intelligence (AI), IoT and other technologies to achieve full automation and intelligent management of production lines. Foundries can use AI algorithms to optimize casting parameters and IoT sensors to monitor the production process in real time, thus further improving yield rates and production efficiency.

In addition, the unique advantages of 3D printing in realizing complex lightweight design will help automotive, aerospace and other downstream industries to improve product performance and reduce energy consumption, which is a perfect fit for the requirements of global sustainable development. 3D printing's on-demand production mode and extremely high material utilization (can be recycled more than 90% unbonded powder), also significantly reduces the generation of waste, for the casting industry to bring the environmentally friendly development path for the foundry industry.

concluding remarks 3D printing is not the end of casting, but its innovator. It gives the traditional foundry industry unprecedented flexibility, efficiency and quality assurance through its two core advantages of "moldless" and "digital". It enables foundries to free themselves from the plight of high scrap rates and enter a new era of greater efficiency, competitiveness and embrace of innovation. For any foundry seeking to stand out in a competitive market, embracing 3D printing technology, represented by SanDi Technology, is no longer an optional choice, but a necessary path to the future.

3D打印如何解決鑄造高報廢率問題:革新鑄造工藝,提升品質與效率最先出現在三帝科技股份有限公司

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How 3D printing can eliminate casting shrinkage by optimizing internal structure http://www.hnanf.cn/en/blogs/casting-shrinkage-cavity-issues/ Thu, 21 Aug 2025 08:44:33 +0000 http://www.hnanf.cn/?p=2374 Is casting shrinkage your problem? This article provides an in-depth analysis of how industrial 3D printing can solve the casting shrinkage problem from the root by optimizing the internal structure and shape-following cooling by virtue of the freedom of mold-free design, and achieve a comprehensive improvement in cost, time and quality.

3D打印如何通過優化內部結構來消除鑄件縮孔最先出現在三帝科技股份有限公司

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Shrinkage, as hidden in the casting of the internal "dark wound", is the traditional casting process in a common, difficult to eradicate defects. It not only affects the beauty of the casting, but also directly threatens its strength and mechanical properties. When the molten metal in the solidification process volume contraction, and do not get enough liquid metal supplement, it will be in the casting or the surface of the formation of voids, that is, we often say shrinkage or shrinkage! The  

Eliminating shrinkage holes has always been a complex challenge for foundries and engineers, with traditional methods often relying on experience and adjusting mold design, pouring systems and cooling processes through trial and error . However, with the advent of additive manufacturing technologies, especially industrial-grade sand 3D printing, casting design and production have been revolutionized, providing unprecedented new ways to completely solve shrinkage problems.  

1. Root causes of casting shrinkage: geometrical limitations of conventional molds

To understand how 3D printing solves problems, it is first necessary to deeply analyze the pain points of traditional casting. The main reasons for shrinkage formation can be attributed to two things:

  1. Compensate for shrinkage deficiencies: As a casting solidifies and shrinks, it needs to be constantly replenished with liquid metal through the pouring system and riser. If the replenishment channels are not properly designed or are insufficient, the liquid metal cannot be transported to the areas most in need of replenishment, resulting in the creation of voids. ?
  2. Uneven solidification: If the cooling rate of different areas of the casting is not consistent, the heat is difficult to effectively disseminate, the formation of hot joints (hot spot). These hot spots are the last solidified areas, when the surrounding metal has solidified, they lack the liquid metal supplement, very easy to form shrinkage holes. ?

In conventional casting, molds and cores are manufactured with physical tools whose geometry is limited by machinability and releaseability. For example, the holes drilled for cooling water paths can only be straight lines. . This makes it difficult for engineers to design complex, curved make-up shrinkage channels or follow-through cooling channels inside the mold to precisely control the solidification process, thus increasing the risk of shrinkage defects The  

2. 3D printing solutions: freedom of design to give "life" to molds and dies

The core strengths of industrial sand 3D printers areDesign Freedomcap (a poem)No mold productionIt prints sand molds and cores layer by layer directly from 3D CAD files. . This characteristic radically breaks through the geometric limitations of conventional processes and provides several powerful means of eliminating shrinkage as follows:  

Option 1: Optimize the fill and contraction channel, precise infusion

Using 3D printing technology, engineers can design the optimal make-up shrinkage system inside the mold without having to consider machinability.

  • Integrated pouring system: Traditionally, the sprue system (including the sprue and riser) has to be fabricated and assembled separately. 3D printing allows the entire sprue system, the filler riser and the mold itself to be printed in one piece. This integrated design ensures a seamless connection and precise alignment of the channels, greatly reducing the risk of shrinkage failure due to assembly errors. ?
  • Design of precise filler risers: 3D printing allows the precise design and printing of shrinkage risers above the hot joint areas of the casting, ensuring a constant flow of molten metal to fill the void created by solidification shrinkage. It has been shown that overflow risers above the casting can effectively vent gases, thus reducing porosity defects in the casting. ?
  • Eliminate undercutting and complex structural barriers: In traditional processes, complex undercuts and internal passages require multiple cores to be assembled, which not only increases assembly errors, but can also easily lead to dislodged or misaligned cores. 3D printing allows multiple individual cores to be combined into a single, complex, integrated core, eliminating the need for assembly altogether, and improving the accuracy and quality of the casting. ?

Option 2: Conformal cooling for uniform solidification

For the molds themselves, 3D printing can be equally revolutionary. ByConformal cooling(conformal cooling) technology, which allows the design of cooling channels inside the mold that match the surface contour of the casting. The  

  • Principle: Conventional cooling channels are drilled in straight lines and do not cover all the areas that need to be cooled, resulting in uneven temperatures in the mold . Conformal cooling, on the other hand, uses 3D printing to integrate curved, serpentine cooling waterways into the mold so that they fit snugly on the surface of the casting . ?
  • Advantage: This design results in more uniform cooling and significantly reduces the risk of localized overheating of the mold. A more balanced temperature gradient means that the solidification process is more controlled, radically reducing the formation of hot joints and thus preventing shrinkage. It has been demonstrated that the use of a form-following cooling mold reduces the temperature variation during mold cooling to as low as 18°C, thus significantly reducing the risk of casting warpage. ?

Scenario 3: Digital Simulation and Rapid Iteration to Prevent Problems Before They Happen

The digital workflow of 3D printing provides engineers with valuable opportunities for "trial and error" before going into production. The  

  • Casting simulation software: Engineers can use casting simulation software (e.g. Cimatron) to simulate the flow and solidification of molten metal. If the simulation results show a risk of shrinkage, the mold design can be quickly adjusted, e.g. by changing the location of the sprue or riser, and then tested virtually again. ?
  • Rapid prototyping and iteration: If a physical prototype is required, 3D printing can print a mold or core in hours or days. This allows engineers to iterate and validate designs multiple times at a fraction of the cost and speed. This agile development model is unimaginable in traditional casting, which requires expensive mold making and long waiting times. ?

3. Not just eliminating defects, but a leap in efficiency

The use of 3D printing technology to solve the problem of casting shrinkage, bringing not only the improvement of product quality, but also a series of chain of business value:

  • Reduce costs: 3D printing significantly reduces production costs by eliminating the expensive physical mold and tooling manufacturing aspects . According to research, 3D printing can save up to 50%-90% compared to traditional methods . ?
  • Shorten the delivery time: Mold making time has been reduced from weeks or even months to hours, allowing companies to respond more quickly to market demands . In one case, a company was able to reduce lead times by 9 weeks by using a sand 3D printer. ?
  • Reduce scrap rates: The accuracy and consistency of the molds have been greatly improved, reducing casting defects due to human error or mold wear, thus significantly reducing scrap rates. ?
  • Simplify the process: Consolidating multiple parts into a single integrated component simplifies complex assembly processes and reduces reliance on highly skilled labor. ?

Conclusion: 3D printing - a "cure" for the foundry industry

Casting shrinkage is not an isolated technical problem, but the traditional casting process in the face of complex design and high-precision requirements of the systematic challenges exposed. Industrial sand 3D printers, with their unique technological advantages, offer a "cure" for the problem at its source. It eliminates the risk of shrinkage by giving engineers unprecedented design freedom, enabling them to build optimized internal structures and cooling systems. The  

For the pursuit of excellent quality, efficient production and cost optimization of modern foundry enterprises, 3D printing is no longer dispensable "additional options", but to promote industrial upgrading, in the fierce competition in the market to win the first chance of the key technology. It is not just a piece of equipment, but also to the "digital casting" bridge to the future, so that the former "casting problems" to be solved! The

3D打印如何通過優化內部結構來消除鑄件縮孔最先出現在三帝科技股份有限公司

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2025 Sand 3D Printer Selection Guide: Choosing the Right Machine Parameters Based on Casting Size and Material http://www.hnanf.cn/en/blogs/2025-sand-mold-3d-printer-selection-guide/ Thu, 21 Aug 2025 08:05:26 +0000 http://www.hnanf.cn/?p=2371 2025 How to choose a sand 3D printer? 3DPTEK full-size models (J1600/J2500/J4000) + open-source material process, help foundry enterprises to accurately select the model, reduce costs 30%+, improve the casting accuracy to ±0.3mm.

2025 砂型 3D 打印機選型指南:根據鑄件尺寸、材質選對設備參數最先出現在三帝科技股份有限公司

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In the casting industry towards intelligent process, sand 3D printer with "mold-free, high-precision, complex structure molding" advantage, become the key equipment to enhance the competitiveness of enterprises. However, there are many models of sand 3D printers on the market (molding size from 500×500×500mm to 4000×2000×1500mm, suitable for materials covering silica sand, zirconia sand, ceramic sand, etc.), if the selection is not appropriate, it will not only lead to idle equipment, waste of costs, but also affect the delivery of production due to the substandard quality of printing. This article takes 3DPTEK sand 3D printer as an example to analyze how to accurately match the parameters of the equipment based on the size and material of the casting and maximize the benefits of equipment investment.

I. Equipment selection strategy based on casting size

The size of the casting is a central factor in determining the specification of a sand 3D printer, which needs to be selected with a balance between current needs and future developments:

  1. Statistical analysis of existing casting dimensions
    1. Enterprises need to comprehensively sort out the past 1-2 years of casting orders, categorized by product type (such as automotive parts, aviation structural components, pumps and valves shells), statistics on the length, width and height of each type of casting size range, drawing size distribution histogram. For example, an automobile foundry statistics found that 60% engine block castings in 300-500mm in length, width 200-350mm, height 150-250mm;
    1. Identify the "core size range" with the highest percentage and use it as a basis for filtering printers. As in the case above, 3DPTEK's 3DPTEK-J1800(molding size 1800×1200×1000mm) can easily cover most of the engine block sand printing needs, to avoid "small horse-drawn cart" (equipment molding size is too large, waste of equipment space and printing costs) or "too big to use" (equipment) (equipment molding size is not enough to print large castings).
  2. Considering future business expansion
    1. Combined with the enterprise's market planning for the next 3-5 years, new product development plan, prejudge the casting size changes that may be involved. If you plan to develop the wind power equipment castings business, you need to investigate in advance the size of wind power hubs, blades and other large castings (wind power hub diameter of up to 3-5 meters), to reserve enough space for equipment upgrades;
    1. If large castings are only occasionally undertaken, consider 3DPTEK's 3DPTEK-J4000 Ultra-large size printer (maximum molding size 4000×2000×1500mm), or "sand cut block + combined assembly" printing strategy (3DPTEK equipment supports localized printing, which facilitates the operation of the cut block), to reduce the cost of equipment procurement.
  3. Handling of special size requirements
    1. For castings with special dimensions such as extra-long, extra-wide, extra-thin, etc. (e.g., elongated shaft castings with an aspect ratio of more than 5:1, thin-walled parts with a thickness of less than 5mm), it is necessary to examine the printing accuracy and stability of the equipment in addition to the molding dimensions. 3DPTEK's bonded injection technology ensures that the molding of special-sized castings is performed with a high degree of precision of ±0.3mm, thus avoiding the scrapping of castings due to deviations in dimensions. avoid scrapping the castings due to dimensional deviation.

Second, suitable for the casting material equipment parameters selection

Different casting materials (e.g. cast iron, cast aluminum, cast steel) have different requirements for sand strength, air permeability and gas generation, which need to be matched with the corresponding equipment parameters and material technology:

  1. Material properties and sand demand analysis
    1. Cast iron parts: due to the good fluidity of iron and moderate solidification shrinkage, the strength of the sand mold is required to be high (tensile strength ≥ 0.8MPa) to prevent the sand mold from erosion and breakage during pouring. The high-strength furan resin binder matched with 3DPTEK equipment, together with silica sand, can meet the needs of sand mold printing for cast iron parts;
    1. Aluminum casting: Aluminum liquid solidification speed is fast, easy to absorb air, the sand type is required to have good air permeability (air permeability value ≥ 150) and low outgassing (outgassing ≤ 15ml/g), to avoid casting porosity defects. 3DPTEK's open-source material process can be adjusted according to the needs of the binder formula, suitable for ceramic sand, zirconia sand and other low outgassing, high air permeability sand, to meet the casting of aluminum casting sand print.
  2. Material compatibility and parameter adjustment
    1. The 3DPTEK sand 3D printer supports a wide range of casting sands (including quartz sand, pearl sand, chromite sand, etc.), allowing companies to choose sand materials flexibly according to casting materials and cost considerations. For example, when producing high-end stainless steel castings, zirconium sand (high temperature resistant and chemically stable) is used with 3DPTEK's special binder to improve the sand mold's anti-washout and anti-sticking properties;
    1. The nozzle parameters (e.g., orifice diameter, spraying frequency) and heating and curing parameters (curing temperature and time) of the equipment need to be precisely adjusted according to the characteristics of the sand material and the type of binder. For example, when using fine-grained quartz sand, it is necessary to reduce the diameter of the spray hole (e.g., from 0.3mm to 0.2mm) and increase the spraying frequency to ensure that the binder evenly covers the sand particles; for thermosetting binder, it is necessary to optimize the heating curing curve (e.g., increase the curing temperature from 150℃ to 180℃, and extend the curing time from 30 seconds to 45 seconds), so as to ensure that the strength of the sand pattern curing.
  3. New material application and technical support
    1. As the casting industry's demand for high-performance, lightweight castings increases, new types of sand materials (such as composite sand mixed with metal powders and nano-modified sand) are gradually being applied. 3DPTEK continues to research and develop new material processes that can be customized to meet the needs of enterprises and customize material solutions to help them quickly realize the application of new materials in sand printing.

Comprehensive Advantages of 3DPTEK Sand 3D Printers

  1. Full-size product matrix: 3DPTEK has a full line of sand 3D printers ranging from 1.6 meters to 4 meters in size, including 3DPTEK-J1600Pro,3DPTEK-J1600Plus,3DPTEK-J1800,3DPTEK-J1800S,3DPTEK-J2500,3DPTEK-J4000 A variety of models, such as to meet the different sizes of enterprises, different sizes of castings printing needs, to avoid enterprises due to the limitations of equipment specifications missed orders.
  2. open source material processIt supports users to adjust the binder and sand material formula as needed to reduce the material cost 20%-30%. At the same time, it is equipped with high-performance resin binder, curing agent and cleaning agent to ensure the stable quality of sand molding and solve the problems of material selection and process optimization of the enterprise.
  3. High-precision molding technologyThe company adopts piezoelectric inkjet technology, high-resolution inkjet system, and special binder formula to realize ±0.3mm high-precision printing, which effectively reduces the machining allowance of the castings, improves the quality of the castings and the production efficiency, and is especially suitable for aerospace, automotive and other industries with stringent requirements for precision.
  4. Flexible area molding without sand boxAs 3DPTEK-J4000 Innovative use of sandbox-free flexible area molding technology, support for local printing, can economically and efficiently realize the manufacture of oversized sand molds, compared with the traditional box printing, the equipment footprint is reduced by more than 30%, and the printing cost is reduced by 15%-20%.

Through the above selection strategy based on casting size and material, combined with the comprehensive advantages of 3DPTEK sand 3D printers, enterprises can accurately match the parameters of the equipment to achieve a high degree of compatibility between equipment performance and production needs, and at the same time improve the quality of castings, reduce production costs and enhance market competitiveness.

2025 砂型 3D 打印機選型指南:根據鑄件尺寸、材質選對設備參數最先出現在三帝科技股份有限公司

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Industrial Wax Mold 3D Printer: A Complete Guide to Large-Scale Casting in 2025, 80% Cycle Time Reduction + Accuracy Enhancement Solutions http://www.hnanf.cn/en/blogs/industrial-grade-wax-mold-3d-printer-2025-large-casting-guide/ Wed, 20 Aug 2025 09:21:38 +0000 http://www.hnanf.cn/?p=2365 In the field of large-scale casting (aerospace turbine blades, automotive engine components, heavy machinery shells), traditional wax mold making has long been subject to "long cycle time, low precision, complex junction [...]

工業級蠟模 3D 打印機:2025 年大型鑄造全指南,縮短 80% 周期 + 提升精度方案最先出現在三帝科技股份有限公司

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In the field of large-scale casting (aerospace turbine blades, automotive engine components, heavy machinery housings).Traditional Wax Mold MakingConstrained by the three major pain points of "long cycle time, low precision, and difficulty in realizing complex structures", it takes 2-3 weeks to manually make a set of wax molds for turbine blades, with an error of more than 0.5mm, and it is impossible to complete the design of internal cooling channels. And the design of internal cooling channels cannot be completed.Industrial Wax Molds 3D printer(The emergence of SLS (SLS technology as the core) has completely changed the status quo: large wax molds can be printed in 3 days, with an accuracy of ±0.1mm, and complex structures that are not possible with traditional processes can also be realized. In this article, we will analyze the definition, advantages, workflow, selection guide and 2025 hot models of industrial wax 3D printers, which will provide foundries with hands-on solutions for technological transformation and cost reduction.

I. What is an industrial-grade wax 3D printer? Core Definition + Comparison to Traditional Processes

Industrial-grade wax mold 3D printers are based onSelective laser sintering (SLS) TechnologyIt is an industrial machine for the production of high-precision wax molds made of casting wax powder / wax-like powder, which are fused layer by layer and can be used directly for lost wax investment casting. It has significant advantages over the traditional wax molding process and is especially suitable for large casting scenarios (part sizes above 500 mm):

comparison dimensionIndustrial Wax Mold 3D PrinterTraditional wax molding process (handmade / CNC)
production cycle3-7 days (large wax models)2-4 weeks
Dimensional accuracy±0.1mm±0.5-1mm
Complex structure realizationEasy printing of internal cooling channels, thin-walled honeycomb structuresMultiple sets of wax molds need to be disassembled and are prone to assembly errors.
labor costAutomated printing, one person can operate multiple machinesDependence on skilled tradesmen, high labor costs 300%
Material utilization90% above (unsintered wax powder recyclable)60%-70% (cutting / manual waste)
Design IterationCAD files can be reprinted within a few hours after modification.Need to remake the mold, long cycle time

The 4 core benefits of industrial-grade wax mold 3D printers for foundries (solving industry pain points)

1. Reduced cycle time 80% for fast response to order requirements

It takes 3 weeks to make a wax mold of a large automotive engine block using traditional processes, but an industrial-grade 3D printer can do it in just 3 days. An aerospace foundry used LaserCore-5300 to print a wax model of a turbine blade, from design to finished product in 48 hours, shortening 80% compared with the traditional process, and compressing the trial production cycle of a new product from 3 months to 1 month, thus seizing the first opportunity in the market.

2. 5 times higher accuracy and lower casting scrap rate

Industrial-grade wax mold 3D printer has an accuracy of ±0.1mm and surface finish Ra≤1.6μm, which can reduce the casting post-treatment process. Due to the large error of wax mold made by traditional process, the casting scrap rate is more than 15%; while the 3D printed wax mold reduces the scrap rate to below 5%, and a foundry produces large valve castings and reduces the loss of scrap by 800,000 RMB annually.

3. Breaking through structural limitations and realizing difficult casting

No need to consider "mold release" issues, allowing for designs not possible with conventional processes, especially for high-end manufacturing:

  1. Aerospace:Multi-layer cooling channels inside the turbine blades(The traditional process requires 5 sets of wax molds to be disassembled, while 3D printing molds the mold in one go, with no assembly errors);
  2. Cars:Engine block integrated runners(Reduced post-drilling process and increased fluid efficiency by 10%);
  3. Heavy machinery:Thin-walled honeycomb structure for large shells(Wall thickness as low as 2mm, weight reduction 20%, strength increase 15%).

4. Long-term cost reductions 40%, offsetting equipment investment

Despite the high initial investment ($50,000+) for an industrial-grade wax-molded 3D printer, the cost advantage is significant when calculated over the full lifecycle:

  • Eliminate mold costs: Traditional large CNC wax mold mold costs over 200,000 yuan, 3D printing can be completely eliminated;
  • Reduced labor costs: 1 person can operate 3 machines, reducing 80% labor compared to the traditional process;
  • Reduction of scrap loss: precision improvement has reduced the casting scrap rate from 15% to 5%, saving more than 500,000 yuan in material cost per year.

Industrial Wax Mold 3D Printing Workflow: 6 Steps from Design to Wax Mold (for Large Casting)

The industrial wax 3D printing process is highly automated and does not require complex human intervention. The core steps are as follows (for example, wax molding of a large turbine blade):

  1. Digital Design and OptimizationThe 3D model of the wax mold is constructed in SolidWorks/AutoCAD, the shrinkage is reserved according to the casting metal properties (e.g. steel needs to be enlarged from 1%-2%), and the structure of the sprue and the vent is designed and exported as an STL format file;
  2. Device parameter settingLoad casting wax powder into a printer (e.g. LaserCore-6000) and set the parameters: layer thickness 0.08-0.35mm, laser power 55-300W, molding rate 80-300cm3/h to ensure that it is suitable for large wax models;
  3. automated printingAfter the equipment is started, the laser sinter the wax powder layer by layer according to the slicing trajectory. It takes 10-20 hours for a large wax model (e.g. 1050×1050×650mm) to be printed unattended at night without human intervention;
  4. Cleaning up after printingAfter the wax mold is completed, remove it from the molding chamber, blow off the excess wax powder on the surface with compressed air (this wax powder can be recycled directly), and inspect the wax mold for holes and cracks (the defect rate of 3D printed wax molds is less than 1%);
  5. Wax mold assembly (mass production)If batch casting is required, individual wax molds are attached to a "wax tree" to improve pouring efficiency;
  6. Suitable for lost wax castingThe wax mold is immersed in ceramic slurry to form a high-temperature-resistant ceramic shell, which is then burned in a 700-1000°C kiln to remove the wax mold (the ash content of the 3D printing wax mold is <0.1%, and the combustion is complete with no residue), and then the metal can be poured in.

How to choose industrial-grade wax 3D printers for foundries? 4 core selection criteria

1. Prioritizing molding space: adapting to the needs of large-scale casting

Large casting parts (such as automotive engine blocks, aerospace frames) with dimensions of 500-1000mm, need to choose the molding space ≥ 500 × 500 × 500mm model:

  • For small and medium-sized foundries (part sizes 500-700mm): A model with a molding space of 700×700×500mm (e.g. LaserCore-5300) is available;
  • Large foundries (part size 700-1000mm): We recommend a model with a molding space of 1050 x 1050 x 650mm (e.g. LaserCore-6000).

2. Technology Type Lock SLS: Ensuring strength and precision of wax molds

SLS technology sintered wax powder by laser, the wax molds have high density (≥0.98g/cm3) and high strength (flexural strength ≥15MPa), which can withstand the external force during ceramic paste coating and handling to avoid deformation. Wax molds made by other technologies (e.g. FDM) have low strength, are easily damaged and are not suitable for large-scale casting.

3. Focus on core parameters: accuracy, speed and material compatibility

  • accurate: Choose a ±0.1mm model to ensure casting dimensions are met and to minimize post-processing;
  • Molding rateThe priority is given to models with more than 200 cm3/h (e.g. AFS LaserCore-6000 up to 300 cm3/h) to increase the efficiency of the production of large wax molds;
  • Material compatibility: A wide range of casting waxes (e.g. low ash casting waxes, high temperature waxes) are required to support the casting of different alloys (aluminum alloys, steel, titanium alloys).

4. Software and services: making the transition less difficult

  1. The software must be compatible with the main CAD formats (STL/OBJ) and come with casting simulation (optimization of the structure of the wax model and reduction of defects);
  2. Service providers need to provide full-process support: free operator training (to ensure that the operation is mastered within 3 days), equipment installation and commissioning, 24-hour after-sales response (domestic door-to-door service ≤ 24 hours).

V. 2025 industrial-grade wax mold 3D printer popular models recommended (suitable for different casting needs)

Based on industry feedback and actual application cases, the following 3 models in 2025 are outstanding in the large casting field, covering entry to high-end scenarios:

modelsMolding space (mm)Type of technologyaccurateMolding rateApplicable ScenariosCore Advantages
AFS-500 (entry level)500 x 500 x 500SLS±0.1mm80-150cm3/hIndustrial tools, small and medium-sized castings (up to 500mm)Cost-effective, low power consumption (15KW), suitable for small and medium-sized foundry trial production
LaserCore-5300 (mid- to high-end)700 x 700 x 500SLS±0.1mm150-250cm3/hAerospace turbine blades, automotive parts (500-700mm)Rapid iteration, stable accuracy, suitable for multi-material printing
LaserCore-6000 (high-end)1050 x 1050 x 650SLS±0.1mm250-300cm3/hLarge automotive engine blocks, aerospace frames (700-1000mm)Extra large molding space, high efficiency of mass production, suitable for high production foundries

Model highlights analysis

  1. AFS-500Low entry cost, easy to operate, 1 person can manage multiple machines, suitable for small and medium foundries trying 3D printing for the first time, for small and medium-sized wax molds such as industrial tools, valves, and so on;
  2. LaserCore-5300The wax molds of turbine blades are widely used in the aerospace industry. The wax molds have a high surface finish and do not need to be polished, increasing the yield of the castings to more than 95%;
  3. LaserCore-6000The machine is one of the few in China that can print 1050mm wax models, and can nest 20 small and medium-sized wax models (e.g., automotive parts) in a single run, which increases the utilization rate of the machine by 60%.

Industrial Wax Mold 3D Printing Common Problems + Expert Solutions

1. High initial investment in equipment? -- Phased investment reduces risk

Small and medium-sized foundries can purchase entry-level models (e.g., AFS-500) for wax molding of high value-added parts (e.g., precision valves), quickly recoup their costs through high-margin orders, and then upgrade to higher-end models after 1-2 years.

2. Incomplete burning of wax molds leading to defective castings? -- Optimization of sintering and firing parameters

  1. When printing: Adjust the laser power (55-80W) to ensure that the sintered density of the wax mold is ≥0.98g/cm3 and to reduce the internal porosity;
  2. Firing: gradually increase the kiln temperature from 700°C to 1000°C and hold for 2-3 hours to ensure complete vaporization of the wax model (can be verified by the change in weight of the ceramic shell).

3. Wax powder recycling is difficult, material waste? -- Configure automated recycling system

By choosing the wax powder recycling equipment with automatic screening and drying function, the unsintered wax powder can be reused directly after treatment, and the material utilization rate is increased from 90% to more than 95%, which saves 200,000 yuan of material cost per year.

4. Unskilled team operation, affecting productivity? -- Give preference to "equipment + training" as an all-in-one service.

Choose a service provider that provides free training (such as AFS brand), 1 to 1 teaching operators to master the daily operation of the equipment, troubleshooting, to ensure the normal operation of the equipment.

VII. Conclusion: Industrial-grade Wax Mold 3D Printer, "Must-have Equipment" for Foundry Transformation

In the increasingly competitive large-scale foundry industry, "high precision, fast cycle time, low cost" has become the core competitiveness -- industrial-grade wax mold 3D printers help foundries break through the limitations of traditional processes by shortening the cycle time by 80%, increasing the accuracy by 5 times, and reducing the cost by 40% in the long run. to help foundries break through the limitations of traditional processes.

In 2025, the commercialization of models such as the LaserCore series will provide a fast track from design to wax mold for industries such as aerospace, automotive and heavy machinery. For foundries, choosing the right industrial-grade wax 3D printer will not only reduce costs and increase efficiency, but also unlock difficult casting orders and secure a place in high-end manufacturing - the core value of industrial-grade wax 3D printing in the future of the foundry industry.

工業級蠟模 3D 打印機:2025 年大型鑄造全指南,縮短 80% 周期 + 提升精度方案最先出現在三帝科技股份有限公司

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4-Meter Large-Scale Sand Casting 3D Printer: Unlocking Large-Scale Casting Manufacturing by 2025, Reducing Cycle Time by 80% + Cost Reduction Solutions http://www.hnanf.cn/en/blogs/4-meter-class-large-sand-mold-casting-3d-printer/ Wed, 20 Aug 2025 07:58:59 +0000 http://www.hnanf.cn/?p=2360 In the field of large casting manufacturing (e.g., engine blocks, industrial machinery shells, aerospace components), the traditional sand molding process has long been subject to "size limitation, long cycle time, high cost [...]

4 米級大型砂型鑄造 3D 打印機:2025 年解鎖大型鑄件制造,縮短 80% 周期 + 降本方案最先出現在三帝科技股份有限公司

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In the field of manufacturing large castings (e.g. engine blocks, industrial machinery housings, aerospace components).Traditional sand molding processConstrained by the three major pain points of "size limitation, long lead time and high cost" for a long time - it takes several months to make a 4-meter sand mold, and it needs to be assembled manually by disassembling several groups of sand cores, with a scrap rate of more than 15%.4-meter large-scale sand casting 3D printer(in the form of) 3DPTEK-J4000 On behalf of the emergence of), completely break this dilemma: 1 time printing to complete the 4-meter overall sand, shorten the cycle of 80%, reduce the cost of 40%, but also to achieve the complex internal structure of the traditional process can not be completed. In this paper, we will analyze the core parameters, advantages, application scenarios and industry value of this equipment, and provide technical transformation guidelines for heavy manufacturing enterprises.

First, the 4 major pain points of the traditional large-scale sand molding process, 4-meter 3D printing how to crack?

Traditional large-scale sand mold manufacturing (size over 2 meters) needs to go through "mold making - sand core disassembly - manual assembly", there are difficult to solve the pain points, but 4-meter sand 3D printing through the "integrated molding + digital process" to achieve a comprehensive breakthrough. process" to realize a comprehensive breakthrough:

Type of pain pointStatus of traditional crafts4-Meter Sand 3D Printing Solution
long lead time4-8 weeks to produce a 4-meter sand mold (2-4 weeks for molding alone)2-5 days to complete the entire sand mold printing, full cycle time reduction 80%
Structural limitationsComplex internal channels, topology optimization structure requires more than 10 groups of sand cores to be disassembled, which is prone to assembly errors.Print complex structures in one piece, no need to disassemble, error ≤ 0.3mm
high costLarge metal molds cost over $500,000 and require 10 people/day for manual assembly.No mold costs, automated printing reduces 80% labor
High scrap rateSand core splicing gaps lead to casting defects, scrap rate 15%-20%Seamless sand molding + simulation optimization to reduce scrap rate to below 5%
4 meters, large sand 3D printer

Second, 4-meter-class large sand 3D printer core analysis: 3DPTEK-J4000 parameters and technical advantages

1. Key parameters: meeting the full scenario requirements for large castings

3DPTEK-J4000 As a benchmark equipment in the industry, it is not a simple enlargement of a small printer, but an exclusive design for large-scale sand manufacturing with the following core parameters:

  1. Maximum molding size: 4000mm x 2000mm x 1000mm (can print the whole sand pattern of 4 meters long and 2 meters wide without splicing);
  2. Process Type: Inkjet binder injection (3DP), suitable for special casting sands such as quartz sand, ceramic sand and ceramic sand;
  3. Accuracy and Resolution: Dimensional accuracy ±0.3mm, nozzle resolution 400dpi, surface finish up to Ra6.3μm;
  4. Layer thickness and efficiencyLayer thickness can be adjusted to 0.2-0.5mm, and 2-3 sets of medium-sized sand patterns (e.g. 2-meter-long pump body sand patterns) can be printed in a single day;
  5. Material utilization: 100% of uncured sand recycled with less than 5% of material waste.

2. Core technology: "sand-free flexible area molding" cost reduction

Traditional 4-meter sand molding equipment needs to be fixed large sand box, a single print needs to be filled with tens of tons of sand, the cost is extremely high. And 3DPTEK-J4000 A breakthrough was achieved with the "Sandless Flexible Area Molding Technology":

  • Eliminates the need for a fixed sand box, dynamically adjusts the sand bed area to the size of the sand pattern, and reduces the amount of 70% sand used;
  • Elimination of large sanding box infrastructure investment (traditional sanding box cost more than 200,000 yuan);
  • Equipment purchase cost is the same as 2.5-meter class equipment, with a 50% return on investment.

The 5 core advantages of 4-meter sand 3D printing: directly enhancing enterprise competitiveness

1. Shorter cycle time 80% to seize the market opportunity

It takes 6 weeks to make a 4-meter engine block sand mold by traditional process, but 3DPTEK-J4000 takes only 3 days to finish printing, and the whole cycle from design to casting delivery is compressed from 3 months to 1 month. A heavy machinery company used it to make large gearbox shell sand mold, new products on the market 2 months ahead of schedule, to seize a share of 30% market segment.

2. Achievement of "oversized + complex" integrated molding

No need to consider the constraints of "stripping" and "splicing" of conventional processes, making it possible to accomplish difficult designs:

  • Aerospace: 4-meter-long turbine casing for theInternal multi-layer cooling channels(The traditional process requires 12 sets of sand cores to be disassembled, while 3D printing molds them in a single pass);
  • Energy sector: 3-meter diameter wind turbine flangesTopology-optimized weight-reducing structures(Weight reduction 20%, strength increase 15%);
  • In the field of industrial machinery: 4-meter-long pump bodies for theSpiral Worm Structure(No splicing seams, 8% increase in fluid efficiency).

3. Long-term cost reduction 40% with short payback period

Despite the high initial investment in the equipment, the cost advantage is significant when calculated over the full life cycle:

  1. Save mold cost: large castings need to replace 2-3 sets of molds per year, 3D printing can be completely eliminated, saving more than 1 million yuan per year;
  2. Reduce scrap loss: a foundry with its production of large valve sand mold, scrap rate from 18% to 4%, reducing annual losses of 500,000 yuan;
  3. Digital inventory: sand patterns are stored as CAD files, eliminating the need to stack physical patterns in the warehouse and saving 100 square meters of storage space.

4. Support "batch + customized" dual-mode production

The 4-meter molding space not only prints large sand molds, but also allows for the nested mass production of small parts:

  1. 200 small pump body cores can be nested in a single print run (traditional processes require batch production);
  2. Supports "1 set of large sand molds + batch of small sand cores" mixed printing, increasing equipment utilization by 60%;
  3. Fast response to customization needs, modifications to the design only require updating the CAD file, no need to recreate the mold.

5. Comply with environmental requirements and help green production

Global environmental regulations are tightening (e.g., China's "dual carbon" policy, EU carbon tariffs), and 4-meter sand 3D printing meets environmental needs through two major technologies:

  1. Use of low VOC binders (emissions below national standard 60%) to reduce air pollution;
  2. Sand 100% is recycled and reused, reducing solid waste emissions by more than 100 tons per year, which meets the requirements for green factory certification.

Fourth, 4-meter sand 3D printing 4 major industry application scenarios (with actual cases)

1. Automotive and commercial vehicle sector: core components for new energy trucks

  • Application: 4-meter long new energy heavy truckIntegral motor housingThe sand molding of large engine block;
  • Case in point: a car company uses 3DPTEK-J4000 Printing the sand mold of the motor shell, the cycle time is shortened from 4 weeks to 3 days, and the casting has no defects at the thin wall (2.5mm), realizing a weight reduction of 30% for the motor and a range increase of 100km.

2. Aerospace and defence: large lightweight structural components

  • Application: 4 meters longAero-engine turbine casing, Missile Launcher Tank Sand Type;
  • Advantage: integrated printing to avoid sand core splicing errors, casting dimensional accuracy up to CT7 level, to meet the aerospace "zero defect" requirements.

3. Industrial machinery and energy sector: core components for heavy equipment

  • Application: 4 meters longLarge Pump Body Worm CasingThe sand molding of wind turbine gearbox shells with a diameter of 3 meters;
  • Case: A heavy industry enterprise uses it to print the sand pattern of the pump body, the surface finish of the fluid channel is improved by 50%, the efficiency of the pump body is improved from 75% to 82%, and the annual energy consumption is saved by 1.2 million yuan.

4. In the field of art and architecture: oversized bronze sculptures

  • Application: 60 meters long bronze sculptureSegmented sand molding(e.g. the "Nine Horses" sculpture in Nanjing);
  • Benefits: Eliminates the need for large wood moldings, allows for complex artistic textures, and reduces the sculpture production cycle from 1 year to 3 months.

Fifth, choose the right solution: 3DPTEK "equipment + ecological" integrated services

The success of 4-meter sand 3D printing requires not only high-quality equipment, but also a complete ecological support. 3DPTEK provides "end-to-end" solutions to reduce the difficulty of enterprise transformation:

  • Proprietary materialsMore than 30 sand-binder formulations (e.g., low viscosity binder for aluminum alloy casting, high temperature resistant binder for steel casting) ensure casting quality;
  • intelligent software: It comes with casting simulation system, which can simulate the flow of metal liquid, cooling contraction, optimize the sand design in advance, and reduce the cost of trial and error;
  • Full Process Service: Full process support from CAD modeling, sand printing to post-processing of castings, free operator training (3 days to master the operation of the equipment);
  • after-sales service24-hour door-to-door service at home, 5 service centers abroad (Germany, the United States, India, etc.), spare parts arrival cycle ≤ 72 hours, to ensure that the equipment is on throughout the year ≥ 95%.

Future Trends in Large-Scale Sand 3D Printing in 2025: Toward "Bigger and Smarter"

1. Continuing size breakthroughs: 6-10 meter class devices in development

3DPTEK has started the research and development of 6-meter-class sand printer, which can realize the whole printing of "8-meter-long ship propellers" and "10-meter-diameter nuclear power equipment shells" in the future, and completely eliminate the defects of large casting splicing.

2. AI+3D Printing: Realizing Intelligent Control of the Whole Process

Integrated AI system for automated completion:

  • Optimization of sand mold design (automatically generate the optimal structure according to the casting material and size);
  • Printing process monitoring (real-time adjustment of binder injection volume to avoid sand cracks);
  • Quality prediction (AI algorithms predict possible defects in castings and adjust the process in advance).

3. Multi-material composite printing: expanding application boundaries

The future equipment can realize "sand + metal powder" composite printing, printing high-temperature-resistant metal coatings on key parts of the sand mold (e.g., the sprue), adapting toTitanium alloy, ultra-high strength steelRefractory alloy casting, expanding the application in the field of high-end equipment.

Conclusion: 4-meter sand 3D printing opens a new era of large casting manufacturing

For heavy manufacturing enterprises, 4-meter-class large sand casting 3D printer is no longer a "technological novelty", but a "necessity to enhance competitiveness" - it breaks the traditional process of It breaks the size and cycle time limitations of traditional processes, and realizes the triple breakthrough of "large-scale + complexity + low cost".

The commercialization of 3DPTEK-J4000 and other equipment has provided a fast track from design to casting for automotive, aerospace, industrial machinery and other industries. In the future, with the research and development of 6-10 meter-class equipment and the integration of AI technology, large casting manufacturing will enter a new stage of "full digitalization, zero defects and greening", and the enterprises that take the lead in laying out this technology will have an absolute advantage in the market competition.

4 米級大型砂型鑄造 3D 打印機:2025 年解鎖大型鑄件制造,縮短 80% 周期 + 降本方案最先出現在三帝科技股份有限公司

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Sand 3D Printing: Reshaping the Metal Casting Industry by 2025 with 80% Cycle Time Reduction + Cost Reduction Solution Explained http://www.hnanf.cn/en/blogs/sand-mold-3d-printing-technology-transforming-the-metal-casting-industry-by-2025/ Wed, 20 Aug 2025 06:17:48 +0000 http://www.hnanf.cn/?p=2358 How Sand 3D Printing Technology Reinvented Metal Casting? 2025 Analyzing its core advantages of shortening 80% sand cycle time and reducing cost by 40%, breaking through the limitations of complex structures, with 3DPTEK equipment parameters and case studies from automotive/aerospace industry to help foundries transform.

砂型 3D 打印技術:2025 年重塑金屬鑄造行業,縮短 80% 周期 + 降本方案解析最先出現在三帝科技股份有限公司

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In the metal casting industry, theConventional sand mold makingLong limited by "long cycle time, low complexity, high cost" three major pain points - the production of a set of complex sand mold takes weeks, and it is difficult to realize the internal cooling channels, thin-walled structure and other complex designs. Andsand mold 3D printing technology(The emergence of (binder jetting technology as the core) has completely changed the status quo: it takes only 24-48 hours from the CAD model to the finished sand model, complex structures are molded in one go, and the material utilization rate is increased by more than 90%. This article will comprehensively analyze the principle of sand 3D printing, core advantages, industry applications and 3DPTEK equipment selection, to provide foundries with technical transformation and cost reduction and efficiency of the practical guide.

I. What is Sand 3D Printing? Core Definition + Process Characteristics (different from traditional mold making)

Sand 3D printing is based onPrinciples of Additive ManufacturingThis is an industrial technology that directly transforms digital CAD models into solid sand molds / cores. Instead of the traditional "mold-making - sand-turning" process, the sand mold is formed by laying sand layer by layer on the printer and curing it by spraying a binder. The core process isBinder jetting technologyThe J1600Pro, J2500, and J4000 models from 3DPTEK, for example, offer significant advantages over conventional molding:

comparison dimensionSand 3D PrintingTraditional mold making process
production cycle24-48 hours2-4 weeks
Complex structure realizationEasy printing of internal channels, thin-walled partsDifficult to realize, need to split multiple sand cores
Tooling CostsNo need for physical molds, cost is 0Customized wood / metal molding required, high cost
Material utilization90% or more (uncured sand can be recycled)60%-70% (much cutting waste)
Design FlexibilitySupports real-time modification of CAD models for fast iterationModification of the design requires re-modeling and long lead time

Second, the foundry must use sand 3D printing 4 core reasons (to solve the industry pain points)

1. Reduced cycle time 80% for fast response to order requirements

While traditional processes take 2-4 weeks to produce complex sand molds (e.g. pump bodies, turbine casings), sand 3D printing takes only 1-2 days. Especially suitable forPrototype molding, small batch customization, emergency spare parts productionScenario -- A foundry uses the 3DPTEK J1600Pro to print sand molds of pump bodies from design to delivery in just 36 hours, a reduction of 80% compared to the traditional process, helping to bring products to market 2 weeks earlier.

2. Breaking through structural limitations and realizing difficult casting

Sand 3D printing eliminates the need for "mold release" issues, making it easy to create designs that would be impossible with traditional processes:

  1. in the field of aerospaceTurbine blade internal cooling channels(The traditional process requires more than 5 sets of sand cores to be disassembled, which is prone to assembly errors);
  2. AutomotiveLightweight thin-walled motor housing(Wall thickness can be as low as 2mm, conventional sand type is prone to fracture);
  3. industrial machineryIntegrated oil passages transmission housing(Reduces post-drilling process and reduces scrap rate).

3. Long-term cost reductions 40%, offsetting equipment input costs

Despite the high initial investment in sand 3D printers, the cost advantage is significant when calculated over the full life cycle:

  • Elimination of mold production costs (a set of large metal mold cost more than 100,000 yuan, 3D printing can be completely eliminated);
  • Reduced scrap rate (digital design + simulation optimization, casting scrap rate reduced from 15% to less than 5%);
  • Reduced labor costs (automated printing eliminates the need for manual assembly of multiple sand cores, reducing labor by 50%).

4. Comply with environmental requirements and realize green production

As global environmental regulations tighten (e.g., the EU REACH standard), sand 3D printing meets the need for environmental protection through two main technologies:

  • adoptionLow Emission Binder(3DPTEK proprietary formulation with VOC emissions below industry standard 50%);
  • Uncured sand can be 100% recycled, reducing solid waste generation and environmental treatment costs.

Three, sand 3D printing principle: 4 steps from design to sand (full process automation)

Sand 3D printing (binder jetting technology) is a simple, highly automated process that requires no complex human intervention, with the following core steps:

  1. Digital Design and Simulation: Engineers use CAD software to build sand models, and simulate the flow of liquid metal, cooling and shrinkage processes through the 3DPTEK casting simulation system to optimize the pouring system and riser position of the sand model, so as to avoid defects such as shrinkage holes and porosity in the castings;
  2. Layer-by-layer molding: The printer automatically lays down 0.26-0.30mm thick sand (quartz sand/chromite sand optional) and then, based on the slicing data, sprays the binder on the area to be cured and builds up the sand pattern layer by layer;
  3. Curing and sand cleaning: After printing, the sand model is left to cure (strengthen) in a closed environment for 2-4 hours, after which the uncured loose sand (which can be recycled directly) is blown out with compressed air;
  4. Casting and post-processingThe molten metal (aluminum alloy, steel, copper alloy, etc.) is poured into the sand mold, which is then cooled, cracked and removed for finishing - the entire process requires no human intervention in the sand mold making process.

Parameters of 3DPTEK Sand 3D Printer (Applicable to Different Industries)

3DPTEK, as an industry leader, has introduced several models of sand printers covering small to very large casting needs with the following core parameters:

modelsPrint size (L × W × H)layer thicknessApplicable ScenariosSuitable for casting alloys
3DPTEK-J1600Pro1600×1000×600mm0.26-0.30mmSmall and medium-sized sand molds (e.g., motor housings, small pump bodies)Aluminum, cast iron
3DPTEK-J25002500×1500×800mm0.26-0.30mmMedium to large sand molds (e.g. gearbox housings, turbine housings)Steel, copper alloys
3DPTEK-J40004000×2000×1000mm0.28-0.32mmOversized sand molds (e.g. ship propellers, large valves)Stainless steel, specialty alloys

Core AdvantagesAll models support "sand + binder" custom formulations, and 3DPTEK has over 30 proprietary formulations to match the needs of different alloys (e.g., aluminum alloy casting for low-viscosity binder, steel casting for high-temperature-resistant sand).

V. Sand 3D printing 4 major industry application scenarios (with actual cases)

1. The automotive sector: core support for the electrification transition

  • Application Scenarios:Electric vehicle water-cooled motor housing, lightweight battery tray sand molding.;
  • Example: A commercial electric truck manufacturer used the 3DPTEK J2500 to print a sand mold of the motor case, realizing an "integrated cooling channel" design, which improved the motor cooling efficiency by 30%, while reducing the weight of the case by 25% and increasing the range by 50km.

2. Aerospace industry: high-precision casting of complex parts

  • Application Scenarios:Turbine blades, aero-engine combustion chamber sand molding.;
  • Advantage: The dimensional accuracy of the sand mold reaches CT7 level, which meets the requirement of "zero error" for aerospace parts, and at the same time, avoids the scrapping of blades caused by the assembly error of traditional sand cores.

3. Industrial machinery industry: core components for large equipment

  • Application Scenarios:Sand molding of large pumps and compressor housings.;
  • Case: A heavy industry enterprise used 3DPTEK J4000 to print a 4-meter-long pump body sand mold, the traditional process requires the production of three sets of metal molds (costing more than 300,000 yuan), 3D printing directly eliminates the cost of molds, and shortens the production cycle from 4 weeks to 3 days.

4. Energy and marine industry: manufacture of very large castings

  1. Application Scenarios:Ship propeller, wind turbine shell sand molding.;
  2. Advantage: The J4000 model's 4-meter wide print size allows for the printing of very large sand molds in one pass, eliminating the need for splicing and reducing mold-fitting defects in castings.

Why choose 3DPTEK sand 3D printing solution? (4 core competencies)

1. Full-scene equipment coverage, adapting to different capacity needs

From 1.6-meter compact machines (J1600Pro) to 4-meter ultra-large machines (J4000) forSmall batch trial production to large scale mass productionThe J1600Pro is available for small and medium-sized foundries with a capacity of 5-8 sand molds per day, and the J4000 is available for large foundries with a capacity of 2-3 oversized sand molds per day.

2. Proprietary material formulas to ensure casting quality

3DPTEK has more than 30granuleExclusive formulation for bonding agents, optimized for different alloys:

  1. Aluminum alloy casting: low viscosity binder, good sand permeability, reduce casting porosity;
  2. Steel casting: high-strength binder, sand mold high temperature resistance (more than 1500 ℃), to avoid the defect of sand washing;
  3. Copper alloy casting: low ash binder to prevent inclusions on the casting surface.

3. Integrated technical support to reduce the difficulty of transition

Provide "equipment + software + service" full-process support:

  1. free of chargeCasting Simulation Software(Optimize sand design and reduce trial and error costs);
  2. Inside the casting technology center, can assist customers in sand testing, casting process debugging;
  3. Provide operator training (1 to 1 instruction to ensure equipment operation within 3 days).

4. Global after-sales network to ensure production stability

The equipment has been landed in more than 20 countries in Europe, Asia, the Middle East, etc., and the after-sales response speed is fast:

  1. Domestic 24-hour door-to-door service (48 hours for remote areas);
  2. 5 service centers abroad (Germany, India, USA, etc.) for quick replacement of spare parts;
  3. Free equipment maintenance 2 times a year to extend the life of the equipment (average life of more than 8 years).

VII. Future Trends of Sand 3D Printing in 2025 (3 Directions to Watch)

1. AI+3D Printing for Zero Defect Casting

The future of sand 3D printing will be integratedAI Design Optimization System-- Input casting parameters (material, size, performance requirements), AI can automatically generate the optimal sand structure, while real-time monitoring of the printing process, by adjusting the amount of binder injection, sand laying thickness, to avoid cracks, uneven density and other problems in the sand, to achieve "zero defects " production.

2. Closed-loop sand recycling, material utilization rate of 98%

exploit (a resource)Automatic Sand Recovery SystemIn addition, the uncured sand and old sand will be screened, decontaminated and recycled, and the material utilization rate will be increased from the current 90% to more than 98%, which further reduces the material cost and meets the requirements of the "Double Carbon" policy.

3. Multi-material composite printing to expand application boundaries

The future of sand 3D printers will enable "sand + metal powder" composite printing - printing metal coatings on critical parts of the sand model (e.g., gates) to improve the sand model's high-temperature resistance, and to accommodateUltra-high strength steel, titanium alloyRefractory alloys such as casting, expanding the application in the field of aerospace, high-end equipment.

VIII. Conclusion: Sand 3D printing is not an "optional technology" but a "must-have transformational tool"

In the increasingly competitive metal casting industry, "fast response, complex structure, green cost reduction" has become the core competitiveness - sand 3D printing by shortening the cycle time of 80%, realizing difficult designs, long-term cost reduction 40% and help foundries break through traditional process constraints.

3DPTEK, as a leading company in the field of sand 3D printing, provides customized solutions for foundries of different sizes through multiple models of equipment, exclusive material formulations, and integrated technical support. Whether in the automotive, aerospace, industrial machinery or energy sectors, choosing sand 3D printing means choosing the double advantage of "cost reduction and efficiency + technological leadership", which is also the core way for foundries to survive in 2025 and beyond.

砂型 3D 打印技術:2025 年重塑金屬鑄造行業,縮短 80% 周期 + 降本方案解析最先出現在三帝科技股份有限公司

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Industrial SLS 3D Printers: A Revolutionary Solution for Precision Manufacturing of Complex Parts, Technology Analysis and Industry Applications 2025 http://www.hnanf.cn/en/blogs/industrial-sls-3d-printer-precision-manufacturing-for-complex-parts/ Wed, 20 Aug 2025 03:41:18 +0000 http://www.hnanf.cn/?p=2355 Learn about the principles, advantages, materials and applications of industrial-grade SLS 3D printers! In 2025, we will analyze how it breaks through the traditional process, realizes the precision manufacturing of complex parts, shortens the cycle time of 70%, and reduces the cost of 40%, and adapts the 3DPTEK equipment to aerospace/automotive/medical/casting scenarios.

工業級 SLS 3D 打印機:復雜零件精密制造的革新方案,2025 年技術解析與行業應用最先出現在三帝科技股份有限公司

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In the wave of transformation and upgrading of the modern manufacturing industry, theHigh precision, high durability, complex structural partsDemand continues to rise. Traditional manufacturing methods are repeatedly limited in small lot production, rapid prototyping and machining of complex geometries, and theIndustrial Grade SLS 3D PrinterWith Selective Laser Sintering (Selective Laser Sintering) technology, become the core equipment to break through these bottlenecks. This article will comprehensively analyze the principle, advantages, applicable materials, industry applications and future trends of industrial-grade SLS 3D printing, to provide manufacturing enterprises with technology selection and production optimization reference.

I. What is an Industrial Grade SLS 3D Printer? Core Definition and Technical Characteristics

Industrial-grade SLS 3D printers use a high-powered laser toNylon, composite polymers, specialty casting sands/waxesThe industrial-grade equipment for selective fusion of powder materials and other materials to build up solid 3D parts layer by layer. Its core technical characteristics are significantly different from desktop-level SLS equipment:

comparison dimensionIndustrial Grade SLS 3D PrinterDesktop SLS Devices
Molding spaceLarge (some models up to 1000mm)few
production efficiencyHigh, supports mass productionLow, mostly single-piece printing
Quality of partsStable and meets mass production standardsLower precision, suitable for prototyping
Material compatibilityHiro (engineering plastics, casting sand, wax)Narrow (mostly basic nylon powder)

In addition, industrial-grade SLS printing requires no support structure (unsintered powder naturally supports the part), making it easy to accomplish things that are impossible with traditional processes.Complex internal channels, lightweight lattice structures, active componentsAll-in-one molding.

4 Core Benefits for Manufacturers Choosing Industrial SLS 3D Printing

In the aerospace, automotive, medical, foundry and other fields, industrial-grade SLS technology has become the key to improve productivity and innovation, the core advantages are reflected in the following four points:

1. No upper limit of design freedom, breaking through the traditional process limitations

No support structure is required, allowing engineers to designComplex internal cavities, integrated moving parts, topology-optimized lightweight structure-- such as hollow structural parts in aerospace and complex runner components in automotive engines -- are difficult to achieve with traditional processes such as CNC machining and injection molding.

2. Strength of parts up to standard, directly used in mass production scenarios

SLS printed parts are not "prototypes" but finished parts with useful functionality. Commonly usedPA12 (nylon 12), PA11 (nylon 11), glass fiber reinforced nylonThese materials have mechanical properties close to those of injection-molded parts, as well as excellent chemical resistance and impact resistance, and can be used directly in mass-production scenarios such as automotive interior parts and medical and surgical tools.

3. Reduced production lead time 70%, rapid response to market demand

From CAD model to finished part, industrial-grade SLS prints in3-7 daysThis is much faster than traditional mold making, which typically takes weeks. For R&D teams in prototype validation, small batch customized production, and emergency spare parts replenishment, this advantage can dramatically shorten the time-to-market cycle and seize the market opportunity.

4. Supporting scale-up and transition production to reduce costs

Industrial-grade SLS equipment can nest dozens or even hundreds of parts in a single print run, making it ideal forSmall batch mass productionSLS can also be used as a "bridge manufacturing" tool - using SLS to quickly produce transitional parts before committing to expensive injection molds, avoiding risky tooling investments and reducing upfront production costs.

Third, the core material of industrial-grade SLS 3D printing: more than nylon, casting application materials into a new hot spot

Nylon is the first material that comes to mind when you think of SLS materials, but industrial-grade equipment has achieved multi-material compatibility and specialized materials, especially in the foundry sector, are driving the digital transformation of traditional casting processes:

1. Foundry sand: direct production of metal casting sand molds / cores

by combiningQuartz Sand / Ceramic SandMixed with a special binder for laser sintering, industrial-grade SLS printers can directly print sand molds and cores for metal casting, with core benefits including:

  • Suitable for pump bodies, turbine housings, automobile engine blocks, etc.Complex internal cavity castings.;
  • Eliminates the need for traditional wood/metal molds, reducing mold costs and lead times;
  • High precision of sand size (error ≤0.1mm), smooth surface, improve the yield of castings.

2. Casting wax: efficient production of wax molds for investment casting

Industrial grade SLS devices can printLow ash casting waxIt is used for investment casting of aviation turbine blades, jewelry, and precision hardware, as opposed to traditional CNC machining of wax molds:

  • Low surface roughness (Ra≤1.6μm) to meet the needs of precision parts casting;
  • Ash content <0.1%, no residue when casting dewaxing, avoid casting defects;
  • Shortened production cycle time 50% for rapid production of small quantities of precision wax molds.

3DPTEK Industrial SLS Casting Equipment Recommendation

As a leading brand in the industry, 3DPTEK offers specialized models for foundry scenarios, adapted to the needs of industrial-grade production:

  • SLS Sand 3D PrinterThe molding length is up to 1000mm, which supports the mass production of large-size casting sand molds and is suitable for casting of large mechanical parts;
  • SLS Wax Mold 3D Printer: High-resolution printing (layer thickness 0.08mm), compatible with standard casting wax formulations for seamless integration into traditional investment casting processes.

Industrial-grade SLS 3D printing works: from design to finished product in 5 steps

The industrial-grade SLS print process is highly automated, with a 5-step core process that eliminates the need for complex manual intervention:

  1. 3D design and pre-processing: Completion of the part design in CAD software, optimization of the structure (e.g., increase of wall thickness, nesting arrangement) by means of special software, and generation of STL files that are recognized by the SLS equipment;
  2. Powder laying: The equipment automatically spreads the powder material evenly on the molding platform, and the layer thickness is controlled at0.08-0.35mm(precision adjustable);
  3. Selective Laser Sintering: High-power laser scanning based on the cross-section trajectory of the part fuses and solidifies the powder particles to form a single-layer part structure;
  4. pile up layer by layer: The molding platform is lowered one level, the machine is re-laid with new powder, and the laser sintering step is repeated until the part is fully formed;
  5. Cooling & Powdering: The parts are cooled slowly in a closed environment (to avoid deformation), and the unsintered powder is removed after cooling (recyclable, with a material utilization rate of more than 90%).

V. Industrial SLS 3D Printer Industry Applications: Typical Scenarios in 4 Major Fields

With the advantages of high precision, high compatibility and fast production, industrial-grade SLS technology has landed in many key industries, and the typical application scenarios are as follows:

1. Aerospace: combining light weight with high reliability

  • give birth to a childLightweight ducting, air handling componentsThe weight of the part is reduced 30%-50% through lattice structure optimization, while strength is guaranteed;
  • Manufacturing of complex structural satellite components, aircraft interior mounts without assembly, reducing the risk of failure.

2. Automotive: rapid prototyping combined with low-volume mass production

  • R&D phase: rapid printingHousing, bracket, dashboard prototypeThe design is validated in 3 days, shortening the development cycle;
  • Mass production stage: small batch production of customized automotive interior parts and maintenance spare parts, avoiding investment in molds and reducing costs.

3. Medical field: personalization and safety at the same time

  • customizablePatient-Only Anatomical Models(e.g., orthopedic surgical planning models) to help physicians accurately develop surgical plans;
  • Produces personalized orthopedic instruments and surgical tools with materials that meet medical grade standards and biocompatibility.

4. Foundry sector: promoting the digital transformation of traditional processes

  • Large metal castings: Direct printing of sand molds/cores for complex parts such as pump bodies and turbine housings;
  • Precision parts casting: Printing of low ash wax molds for investment casting of precision parts such as aerospace turbine blades and jewelry.

Case Study: European Automotive Supplier Uses SLS 3D Printing to Reduce Cost by 40% and Increase Efficiency by 70%

A European automotive supplier needed to customize tooling for a short-term production task. The traditional solution used CNC machining, which required a 10-day lead time and high equipment costs; it switched to CNC machining.3DPTEK Industrial Grade SLS 3D PrinterAfter:

  • Material Selection: High strength PA12 powder is used, the strength of the part meets the requirements of the tooling;
  • Production cycle time: only 3 days from design to finished product, 70% shorter than CNC machining;
  • Cost Control: No need for molds and complex machining, reducing overall costs by 40%;
  • Result: Successful completion of a short production run and verification of the feasibility of SLS technology in tooling manufacturing.

3DPTEK Industrial Grade SLS 3D Printer: Why is it the Industry's Preferred Choice?

Among the many brands of industrial SLS equipment, 3DPTEK has become a popular choice for manufacturing companies due to its "mass-production oriented" design philosophy, which is reflected in its core competence in four ways:

  1. Large size and high speed at the same timeSome models have a molding length of up to 1000mm, which supports the production of oversized parts. Meanwhile, the printing speed is 20% higher than the industry average, which improves the efficiency of mass production;
  2. Strong multi-material compatibilityThe machine can be adapted to a wide range of materials such as engineering plastics, casting sand, casting wax, etc., so that one machine can meet the needs of multiple scenarios;
  3. Full Process Solutions: Provides a wide range of services from printing devices toCasting simulation software, post-processing equipmentThe all-in-one solution eliminates the need for additional third-party tools;
  4. Global Technical Support: Full-cycle service covering equipment installation, operation training and after-sales maintenance to ensure stable operation of the production line.

VIII. Future Trends of Industrial SLS 3D Printing in 2025: 3 Directions of Concern

With the advancement of material science and automation technology, industrial SLS printing will develop to higher efficiency, wider application and higher quality, and the 3 major trends in the future are obvious:

  1. Increased print speed without sacrificing accuracy: Through laser power optimization and multi-laser simultaneous sintering technology, the printing speed will be increased by more than 50%, while maintaining a high accuracy of 0.08mm;
  2. Expansion of material categoriesHigh-temperature composite materials (such as PEEK-based powders) and metal-based composite powders will be gradually landed, expanding the application of SLS in high-temperature and high-strength scenarios;
  3. Closed Loop Intelligent ProductionThe integrated real-time monitoring system monitors the printing process through AI algorithms and automatically adjusts the laser parameters to realize "zero-defect" mass production and reduce the scrap rate.

IX. Conclusion: Industrial Grade SLS 3D Printing, More Than a "Printer", It's a Tool for Manufacturing Innovation

Industrial-grade SLS 3D printers are no longer just "prototyping machines", they are "design-production-application" machines that are capable of linking the entire design-production-application process.Production-grade solutionsIndustrial SLS technology provides efficient, cost-effective solutions to the lightweight needs of the aerospace and automotive industries. Whether it's the lightweight needs of aerospace, the rapid response needs of the automotive industry, the personalization needs of the medical field, or the digitalization needs of the foundry industry, industrial-grade SLS technology provides an efficient, cost-effective solution.

For manufacturing companies, choosing the right industrial-grade SLS equipment (such as 3DPTEK's sand/wax mold models) not only improves productivity, but also breaks through the limitations of traditional processes and seizes the high ground for innovation - which is the core value of industrial-grade SLS 3D printing in the future of manufacturing.

工業級 SLS 3D 打印機:復雜零件精密制造的革新方案,2025 年技術解析與行業應用最先出現在三帝科技股份有限公司

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3D printing sand casting, a must for traditional foundry owners http://www.hnanf.cn/en/blogs/3d-da-yin-sha-xing-zhu-zao-chuan-tong-zhu-zao-chang-lao-ban/ Thu, 20 Mar 2025 08:31:14 +0000 http://www.hnanf.cn/?p=2146 This article analyzes the depth of the technology, from the principle, to solve the core problem, to procurement assessment, talent needs, for the foundry bosses comprehensive interpretation. Help you accurately determine whether to introduce this technology, enhance enterprise competitiveness, realize the transformation and upgrading, seize the market opportunities!

3D打印砂型鑄造,傳統鑄造廠老板必看最先出現在三帝科技股份有限公司

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In the traditional foundry industry, sand mold making has always been a key link affecting productivity, cost and molding capability of complex structure castings. With the increasing market demand for high-precision, short-delivery and complex structure castings, the traditional manual molding and mold manufacturing methods have been difficult to meet modern manufacturing requirements. Sand 3D printers, as an advanced additive manufacturing technology, can directly print complex sand molds and cores without the need for molds, dramatically shortening the production cycle, reducing costs, and enhancing design freedom. In this article, we will discuss why traditional foundries should consider introducing sand 3D printing technology to enhance competitiveness, optimize production processes, and meet market demand for efficient and accurate casting. The following is written exclusively for foundry owners, and we hope it will inspire you.

As a foundry owner, do you encounter this situation often?

--Customers want to do small quantities of trial parts, do a metal mold to 200,000, the result of the order is only 50 pieces, a calculation found that the mold cost more than the money earned, can only give up the order!
--The customer had an order for an aerospace part with honeycomb structure, and the traditional sand core assembly error was bigger than the part size, so it was a big headache to stare at the scrapped casting!
--Competitors with 3D printing took a well-known automotive battery pack orders, their own offer is lower than others 30% or did not win the bid, and finally inquired about the delivery of people faster than us 2 months, very helpless!

--Customers do not move to change the design of the warehouse piled up more than 300 sets of scrap molds, checking the accounts found that the mold inventory occupied half a year of profit, which is too painful to taste!

--Customers sent a complex structure of the pieces over, and said that the price is not a problem, an assessment found that the traditional casting process can not be done, looking at such a high value-added orders can only be given up!

Below we help all bosses one by one to sort out clearly, an article to let you fully understand the 3D printing sand casting technology!

What is sand 3D printing?

Sand 3D printing is a relatively new technology, simply put, is like building blocks, with special materials layer by layer "pile" out of the casting sand.

In the past, the traditional method of making sand molds may need to make molds first, and then use the molds to shape, the process is more complicated, and if you want to make some sand molds with very strange and complex shapes, it will be particularly difficult and costly. But sand 3D printing is different, it works with a 3D model in your computer. You input the data of the 3D model of the designed casting into the 3D printer, and the printer will, according to the shape and structure of the model, put special sand or sand-like materials, according to the layer by layer in a precise way and bonded up, just like using countless thin "sand pieces" gradually built into a complete sand mold. In this way, no matter how complex the shape, as long as it can be designed in the computer, it can be printed out, and the speed is quite fast, and do not need to make complex molds like the traditional method, can save a lot of time and cost it.

Principle of Sand 3D Printer

Sand 3D printing is usually done usingBinder Jetting (BJ)The basic principle is as follows:

  1. spread sand: The printer spreads a specific casting sand (e.g. silica sand, ceramic sand or coated sand) evenly over the printing platform.
  2. spray binder: The spray nozzles precisely spray the binder according to a computer model (CAD data) to bond the sand grains in a specific area.
  3. pile up repeatedly: The platform is lowered, sand is spread again and the binder is sprayed, curing and molding layer by layer until the entire sand print is completed.
  4. reprocess: Remove unbonded loose sand, harden and clean the printed sand model, which can then be used for metal casting.

What are the core problems addressed by 3D printed sand casting?

The existence or birth of each technology must have its "mission". Commonly known as a solution to a particular problem, to meet market demand, this is the value of its existence. Below we take a look at the sand 3D printing technology to solve the thorny problems encountered in the traditional casting, as follows:

  • Manufacture of complex shaped partsTraditional sand casting to manufacture complex shapes is difficult and costly, such as aviation engine blades inside the fine cooling channels, traditional processes are difficult to accurately mold. 3D printing sand based on digital models, can easily turn complex shapes into reality, from the dense concave, raised automotive engine block sand, to have a subtle biomimetic structure of the shell of the medical device sand, can be perfectly rendered.
  • long production lead timeTraditional sand casting need to go through a long process of designing molds, manufacturing molds, debugging molds, large-scale mold manufacturing cycle often exceeds a few months. 3D printing sand without mold production, directly according to the digital model printing, design modification is only required to operate the model on the computer, reprinting can be, can significantly shorten the production cycle. Such as research and development of new automotive engine block, the traditional casting mold scrap remake at least two weeks, 3D printing sand can be completed on the day of the new model printing, the next day can be put into casting.
  • Difficulty in cost controlTraditional casting mold manufacturing material waste is serious, the utilization rate of complex mold materials is less than 30%, and high labor costs. 3D printing sand on-demand printing, accurate sand, material utilization rate of more than 90%, reduce waste. High degree of automation of the printing process can reduce labor costs. Take a small foundry as an example, with an annual production capacity of 5,000 pieces of small pipe fittings castings, after the introduction of 3D printed sand, the material cost will be reduced by 150,000 yuan per year, and the labor cost will be cut by 200,000 yuan.
  • Low precision of castingsThe traditional sand mold due to mold wear, parting surface fitting error, casting size deviation often exceeds ±1mm, subsequent machining allowance, material waste, and prone to local loosening, sand entrapment and other defects, resulting in uneven mechanical properties of the casting. 3D printing of the sand model by the digital model of the precise drive, sand size accuracy of up to ±0.5mm, can achieve uniform compactness, to avoid uneven sand loose, and at the same time optimize the solidification process to significantly reduce shrinkage holes, shrinkage, to ensure reliable internal quality of the casting. At the same time, the solidification process is optimized, greatly reducing shrinkage holes and shrinkage loosening, and ensuring stable and reliable internal quality of castings.
  • High environmental pressureTraditional casting mold manufacturing produces a large amount of waste metal, waste plastic, sand processing waste sand piles up. 3D printing sand production, unused sand can be recycled and reuse, very little waste, and the printing process does not require a large number of chemical binders, reducing the emission of hazardous gases, and improve the workshop environment. According to statistics, after the adoption of 3D printing sand mold, the casting workshop waste emissions reduced by more than 80%, dust, harmful gas concentration of environmental standards.

How does a foundry evaluate if they need to buy a sand 3d printer?

The price of a sand 3D printer is not cheap (usually the larger the size the more expensive), to buy is relatively cautious, especially small and medium-sized foundries. In order to help bosses to assess whether there is a need to buy, we have specially organized the following some evaluation points, to give the boss of the traditional foundry a reference, and then according to their own situation to decide whether to buy:

production requirement

  • Product complexity: If the foundry often produces complex shapes, castings with fine structure or internal channels, such as aero-engine blades, automobile cylinder blocks, etc., the traditional process is difficult to meet the requirements, sand 3D printer can play an advantage.
  • Production size and lot size: For small-volume, multi-variety casting production, sand 3D printers offer the flexibility to quickly switch products without the need to make molds, reducing costs and cycle time. However, for large-scale, single-species castings, traditional processes may be more cost-effective.
  • Delivery period requirementsThe sand 3D printers allow for shorter lead times and quicker order response if the customer has stringent lead times.

cost-effectiveness

  • Investment in equipmentThe cost of purchasing a sand 3D printer, installation and commissioning costs, and maintenance costs need to be taken into account.
  • running cost: Includes printing materials, energy consumption, and labor costs. Compare with the traditional casting process and analyze the high and low long-term running costs.
  • potential gainConsider the potential benefits of using sand 3D printers in terms of improved product quality, shorter cycle times, and lower scrap rates.

technical capability

  • Employee Skills: Evaluate how well your current employees know 3D printing technology and whether you need to train or recruit specialized talent.
  • Technical Support: To understand the technical support capability of the equipment supplier, including whether the services such as installation and commissioning, training and fault repair are timely and effective.

market competition

  • Industry Trends: Keep an eye on your peers to see if they are already adopting sand 3D printing, and if competitors are already using it and gaining an advantage, foundries may need to consider purchasing it in order to remain competitive.
  • client needThe purchase of sand 3D printers can help to meet the needs of customers who want to see foundries adopting advanced technologies to improve product quality and productivity, as well as to increase their competitiveness in the marketplace.

environmental requirement

  • If the local environmental protection requirements are strict, the traditional casting process is under great pressure in terms of waste sand treatment and exhaust gas emission, etc., sand 3D printers can help enterprises meet the environmental protection requirements due to the advantages of high material utilization rate and low waste.

What kind of talent is needed for sand 3D printing?

Considering that many traditional foundry enterprises may not be equipped with 3D printing sand casting related professionals, we have specially organized the position of workers need to have what aspects of the skills and usual job duties, so that factories in the recruitment of reference.

Professional Requirements:

  1. Mechanical Engineering, Materials Science, Foundry Engineering, Additive Manufacturingand other related majors;
  2. Familiarity with sand 3D printing (Binder Jetting) technology and experience in operating related equipment is preferred;
  3. skillful useCAD, 3D modeling software (e.g. SolidWorks, AutoCAD, Magics, etc.), with basic data processing skills;
  4. Understand the casting process, familiar with sand material properties, post-treatment process and common casting defects analysis;
  5. Ability to maintain and troubleshoot equipment and independently solve common problems in equipment operation;
  6. Good teamwork skills, able to work closely with casting engineers and production team to optimize the production process;
  7. Strong learning ability to quickly grasp new technologies and a keen interest in the application of additive manufacturing in the foundry industry.

Job Description:

  1. be in charge ofSand 3D Printerday-to-day operations, including equipment commissioning, print job execution and quality control;
  2. Process 3D printing data, including CAD model optimization, slicing and printing parameter settings;
  3. Supervise the printing process to ensure that the quality of the sand mold meets the casting requirements and that the necessary post-processing (e.g., cleaning, hardening, etc.) is performed;
  4. Responsible for the maintenance of equipment, troubleshooting and solving problems in the printing process to ensure stable equipment operation;
  5. Collaborate with the casting technology team to optimize the process of 3D printing sand molds to improve casting quality and production efficiency;
  6. Research and introduce new materials and processes to continuously improve the application of sand 3D printing in casting production;
  7. Responsible for in-house training of personnel on 3D printing technology to improve the overall technical level of the team.

summarize

In summary, sand 3D printing technology has brought many opportunities and changes for traditional foundries, which can effectively solve a series of thorny problems faced by the traditional casting process, such as the manufacturing of complex shaped parts, long production cycle, difficult to control the cost, poor casting accuracy and environmental protection pressure. Through a comprehensive assessment of production demand, cost-effectiveness, technical capabilities, market competition and environmental requirements, foundry owners can be more scientific and rational judgment whether to introduce sand 3D printer. Equipped with professional technical personnel, is to ensure that this technology in the foundry in the smooth landing, play the key to maximize performance.

In the increasingly competitive foundry market, take the initiative to embrace new technologies, and actively make changes, may be able to seize the first opportunity to realize the transformation and upgrading of enterprises and sustainable development. For traditional foundries, sand 3D printing technology is not only a technology change, but also a breakthrough in the development of bottlenecks, enhance core competitiveness of the perfect opportunity. I hope that all foundry bosses can combine the actual situation of their own enterprises, fully weigh the pros and cons, to make the most suitable for the long-term development of the enterprise's decision-making, so that the enterprise in the tide of the times to ride the waves, sailing to a broader market blue sea.

3D打印砂型鑄造,傳統鑄造廠老板必看最先出現在三帝科技股份有限公司

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What core problem do sand 3D printers solve? This article tells you the truth http://www.hnanf.cn/en/blogs/sand-3d-printers-solve-core-problems/ Sun, 12 Jan 2025 08:24:49 +0000 http://www.hnanf.cn/?p=2083 Many foundries want to buy sand 3D printer but it is not very understanding of what it can solve the core problem, read this article you will be able to understand everything, you can make a preliminary guidance on whether to purchase equipment.

砂型3D打印機解決了什么核心問題?這篇文章告訴你真相最先出現在三帝科技股份有限公司

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In modern manufacturing, casting process has been an important method to produce complex metal parts. However, the traditional casting process faces many challenges, such as the difficulty of molding complex structures, limited customized production, long production cycle, difficult cost control, unstable product quality and environmental issues. With the rapid development of 3D printing technology, sand 3D printers have emerged as a revolutionary tool to solve these problems. In this article, we will delve into how sand 3D printers have changed the foundry industry and analyze the multiple advantages they bring (what core problems they solve).

1. Addressing the limitations of traditional casting processes

Difficulty in molding complex structures 

Conventional casting processes often face enormous technical difficulties and high costs when manufacturing sand molds of complex shapes. For example, aircraft engine blades usually have fine and complex cooling channels inside, the traditional process of manufacturing such molds is extremely difficult. The sand 3D printer through digital modeling and layer-by-layer printing technology, can easily achieve the manufacture of complex shapes of sand molds, greatly reducing the technical threshold and cost.

Customized production is limited 

With the rise of personalized consumption and niche markets, the demand for small-lot, customized castings is growing explosively. However, the traditional casting process, with its high mold opening costs and long customization cycle, is difficult to meet the market's rapid response needs. Sand 3D printers do not require molds and are able to quickly design and print sand molds according to customers' special specifications, shapes and performance requirements, greatly improving the flexibility and efficiency of customized production.

2. Enhancing production efficiency and cost control

long production lead time

Traditional sand casting requires a lengthy process of designing the mold, manufacturing the mold, commissioning the mold, etc. The manufacturing cycle for large molds often exceeds several months. During the period may also be due to design changes or mold defects lead to rework, further extending the production cycle. Sand 3D printers do not need to make molds, directly according to the digital model printing, can significantly shorten the product development cycle, improve production efficiency.

Difficulty in cost control

In the traditional casting mold manufacturing process, the material waste is serious, and the material utilization rate of complex molds is less than 30%. In addition, from the molders to the molding workers, mold repair workers, the manpower investment is large, which further pushes up the cost. Sand 3D printer on-demand printing, accurate sand, material utilization rate of more than 90%. high degree of automation in the printing process, reducing the cost of manpower, significantly reducing production costs.

3. Improving product quality

Low dimensional accuracy

Traditional sand mold due to mold wear, parting surface fitting errors and other issues, casting size deviation often exceeds ± 1mm, subsequent machining allowance, material waste. Sand 3D printer by the digital model precision drive, sand size accuracy up to ± 0.5mm or less, reducing the machining process, reducing costs.

Uneven internal quality

Traditional sand molds are prone to localized looseness, sand entrapment and other problems, resulting in uneven mechanical properties of castings, prone to cracks and other defects. Sand 3D printer can achieve uniform compactness, to avoid uneven sand loose, and at the same time, optimize the solidification process, significantly reduce shrinkage holes, shrinkage, to ensure stable and reliable internal quality of the casting, to enhance the performance and service life of the product.

4. Environmental advantages

Traditional casting mold manufacturing produces a large amount of waste metal, waste plastic, sand processing waste sand piles up. The annual capacity of 10,000 tons of castings of the factory, the annual emissions of waste sand more than 5,000 tons, high treatment costs and pollution of the environment. Sand 3D printer in the production, unused sand can be recycled and reuse, very little waste. In addition, the printing process does not require a large number of chemical binders, reducing the volatilization of harmful gases and improving the workshop environment.

5. Reasons why foundries deserve sand 3D printers

Improvement of production efficiency

Sand 3D printer can quickly respond to market demand, especially suitable for frequent re-modeling of small batch products. It allows foundries to quickly meet customers' individual customization needs and improve customer satisfaction and market competitiveness. At the same time, the sand 3D printer supports mass production, which can print a large number of high-quality sand molds in a short period of time to meet the needs of large-scale production and improve production efficiency and yield.

Reduced production costs

Sand 3D printing technology directly prints sand molds without opening molds, thus greatly reducing the cost of opening molds, especially suitable for small batch and complex structure production needs. In addition, sand 3D printing equipment can be operated with only simple training, and does not require a lot of manpower synergy, which can effectively reduce the dependence on skilled workers, so that foundries can easily cope with the recruitment difficulties and expensive labor problems.

Enhancing Product Quality

Sand 3D printers are more accurate, such as the3DPTEKof 3D printing equipment, which means that the dimensional accuracy of castings is dramatically improved, the one-time pass rate of products is significantly increased, the scrap rate is reduced, and the foundry is allowed to utilize its resources more efficiently. At the same time, the 3D printed sand mold has better precision and surface quality, reduces the amount of grinding and finishing work, makes the production process cleaner, and improves product quality and process consistency.

Optimization of production management

With a compact body design, the sand 3D printer occupies a small area and is flexible to install, which is suitable for the different site layout requirements of small and medium-sized foundries. Modular production solutions can also support easy expansion of enterprises to achieve multi-machine linkage. Part of the sand 3D printer support digital monitoring system, business managers can monitor the production progress and equipment status in real time, to achieve a fully controllable production process, equipment operation data can be automatically stored to facilitate the optimization of production strategies.

6. Concluding remarks

The emergence of sand 3D printers not only solves many problems in the traditional casting process, but also brings unprecedented opportunities for the foundry industry. It provides foundries with strong competitiveness by improving production efficiency, reducing production costs, improving product quality and optimizing production management. With the continuous progress of technology, sand 3D printers will play an increasingly important role in the future of the manufacturing industry, promoting the foundry industry to a more efficient, more environmentally friendly and smarter direction.

砂型3D打印機解決了什么核心問題?這篇文章告訴你真相最先出現在三帝科技股份有限公司

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Explore sandbox-free 3D printers http://www.hnanf.cn/en/blogs/tan-suo-wu-sha-xiang-3d-da-yin-ji/ Tue, 24 Dec 2024 09:25:00 +0000 http://www.hnanf.cn/?p=1940 This article explores sandbox-less 3D printers and how they can provide dimensional flexibility, high accuracy, cost-effectiveness, and design freedom from the limitations of traditional sandboxes to improve manufacturing efficiency. At the same time, it provides readers with an understanding of the innovative value and growth potential of sandbox-less 3D printers in the foundry sector.

探索無砂箱3D打印機最先出現在三帝科技股份有限公司

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This article explores sandbox-less 3D printers and how they can provide dimensional flexibility, high accuracy, cost-effectiveness, and design freedom from the limitations of traditional sandboxes to improve manufacturing efficiency. At the same time, it provides readers with an understanding of the innovative value and growth potential of sandbox-less 3D printers in the foundry sector.

Why is it called a sandbox-less 3D printer?

The boxless 3D printer is so named because it eliminates the use of a traditional box in the sand 3D printing process, significantly differentiating it from conventional sand 3D printers. Here's more about it from a variety of perspectives:

The role and limitations of traditional sandboxesSandboxes are an indispensable part of the traditional sand casting process and some traditional sand 3D printing techniques. It is used to hold the sand, provide molding space for the sand model, ensure that the sand maintains a specific shape during the molding process, and ensure the integrity of the sand model during transportation and box closing. However, the fixed size of the sand box limits the size of the sand mold that can be produced, and the production and maintenance costs are high. For the complex structure of the sand mold, the sand box is difficult to design and manufacture, and it may also affect the heat dissipation and air permeability of the sand mold, which may affect the quality of the castings.

How sandless box 3D printers work: The sandbox-less 3D printer adopts sandbox-less flexible area molding technology, in which abrasive and binder are stacked and molded layer by layer by the nozzle directly on the worktable. The equipment has a precise sand spreading system, which can evenly spread the sand material in the printing area, and the nozzle accurately sprays the binder according to the model cross-section information, so that the sand particles are bonded to form the sand shape layer by layer. In this process, there is no need for a sand box to provide molding space and constraints, which greatly improves printing flexibility and freedom.

Basis of namingThe naming of the 3D printer directly reflects its core technical feature, which is that it is free from the constraints of the traditional sand box, creating a new mode of sand 3D printing. This naming scheme is simple and clear, highlighting the essential difference with the traditional sand 3D printing equipment, and emphasizing its unique advantage of realizing high-precision and high-efficiency manufacturing of sand patterns without the assistance of a sand box during the printing process.

Sandless Box 3D Printer vs. Traditional Sand 3D Printer

There is a clear difference between the working principle of a boxless 3D printer and that of a traditional sand 3D printer. Traditional sand 3D printers rely on a fixed sand box to define the molding space, and rely on the sand box to provide partial support, and the print path is limited by the sand box; while sand box 3D printers use flexible area molding technology, expanding the printing platform on demand, breaking through the size limitations, and supplying the sand and binder with greater precision, and adjusting the internal sand buildup and binder injection to provide support, so the print path is more freely and flexibly planned, and it can effectively improve the printing efficiency and sand quality. It can effectively improve the printing efficiency and the quality of the sand mold.

3dptek-J4000 Sand Mold 3D Printer
Large-size sandbox-less 3D printer: 3DTEPK-J4000

Prospects for sandbox-less 3D printers in the foundry sector

The development of sandbox-free 3D printers in the foundry field is very promising, mainly in the following aspects:

Technological innovation and breakthroughs

Sandbox-free 3D printers continue to realize technological innovations, such as SANDI's 3DPTEK-J4000 Adoption of sandbox-less flexible area molding technology, can be customized to expand the printing platform, the maximum molding 4 meters of sand, to meet the production needs of 10 meters + level, breaking through the traditional casting equipment size limitations, for the manufacture of large and complex castings to provide the possibility of.

Significant cost advantages

On the one hand, the cost of ownership is reduced, as the price of 4-meter and larger boxless 3D printers is comparable to that of 2.5-meter machines, allowing companies to obtain larger sizes of abrasive molds at a lower cost per unit. On the other hand, material waste is reduced, as boxless 3D printers allow precise use of materials such as sand and binder, reducing production costs.

Strong growth in market demand

Aerospace, automotive, energy power and other fields of large, complex, high-precision castings demand continues to rise. For example, the manufacture of aircraft engine components, automotive engine block, etc., sandless 3D printers can meet the high-performance requirements for castings in these fields, the market potential is huge.

Significant increase in design freedom

The sandless box 3D printer can manufacture complex geometric shapes and cavities that are difficult to achieve by traditional methods, realizing parts integration and lightweight design, providing more space for product innovation and helping to improve product performance, reduce costs and enhance the market competitiveness of enterprises.

Significant increase in productivity

Compared to traditional mold making methods, sandbox-less 3D printing of sand molds or cores takes only a few hours to a few days, dramatically shortening the development and production cycle of new products, helping manufacturers respond faster to changes in market demand, and improving productivity and economic efficiency.

Superior environmental performance

Sandless 3D printers use materials on demand, reducing waste and disposal costs of leftover materials, and some of the equipment can use environmentally friendly materials and binders, which reduces environmental pollution, meets the requirements of sustainable development, and helps foundry companies to meet the increasingly stringent restrictions of environmental regulations.

Deepening Industrial Integration

The integration of sand box 3D printer and foundry is deepening, enterprises through mergers and acquisitions of foundries and other ways to open up the "3D printing + casting" process, to provide the whole industry chain overall solution, and promote the foundry industry to the green, intelligent, high-end direction of development.

探索無砂箱3D打印機最先出現在三帝科技股份有限公司

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