3D printing sand casting, a must for traditional foundry owners

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.