Antarctic bear: What are the potential and obstacles of metal 3D printing in the manufacture of heat exchangers?
Conficker Technology, Australia, is a design and engineering company that USES laser Powder Bed Fusion (LPBF) Technology to specialise in 3D printing compact high-performance heat exchangers that include design, developFment, production, and post-processing services.In addition, it has received an investment from AM Ventures, the global 3D printing fund of EOS, the leading industrial 3D printing company in Germany.
Metal 3D printing technology has witnessed rapid development in the past 10 years and has been increasingly applied in aerospace and medical fields.It is also ideal for making heat exchangers.
However, compared with the traditional high performance heat exchanger manufacturing method, additive manufacturing is still a new technology.Experience from Conficker UX indicates that the 3D print exchange is relatively challenging.Success requires a deep understanding of DfAM (design for additive manufacturing), the fundamentals of heat transfer and fluid mechanics, thermal fluid simulation, and additive manufacturing processes.
Below are three key factors considered in the 3D printing heat exchanger:
1. Surface density.The goal is to maximize the surface area packed into a given volume without damaging the design or adding weight.
Products are often compared to conventionally manufactured heat exchangers rather than 3D-printed heat exchangers.The competitive challenge is that traditional methods produce feature walls that are two to three times thinner than the best medium – and large-format laser metal 3D printing systems of their kind.This makes other advantages of additive manufacturing more important.
2. Large CAD and build files.The importance of surface area density means that 3D-printed heat exchangers often contain large and dense arrays of complex features.The result is very large local CAD and build files, making the creation and manipulation of geometry and build data time consuming.
In recent years, some of the development of metal 3D printers has focused on upgrading to production-level platforms with multiple lasers, process monitoring tools, integrated powder recovery and unpacking stations.
Design concept of heat exchanger
3. Product qualification standards.Heat exchanger manufacturers face unique challenges in terms of qualification and certification, as a single defect or pinhole in a thin-walled air-tight structure can mean the difference between equipment executed as designed or not.
Traditionally manufactured heat exchangers are designed and sized according to tables and standards generated over time.This does not mean that traditional methods of manufacturing do not have pain points, but that standards and other guidelines establish some confidence.
Double water supercharged air cooler made of additive (isometric drawing)
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What can be done to speed up and simplify the identification and verification process and increase confidence in 3D-printed heat exchangers?Here are some Suggestions:
– Understanding the nature and location of defects is more critical than trying to eliminate them all.For example, it is sometimes a mistake to focus on the porosity of a part.It is important to understand that porosity does not necessarily have a negative impact on performance.
– Include deep and powerful process procedures in the production process, such as process monitoring, computed tomography, performance, durability and fatigue testing.
– Reduce ambiguities in the 3D printing process, especially in calibration, fine tuning and the uniformity of 3D printers among different metals.This is important because if we were to package a whole set of the same build data (materials, geometries, support structures, processes and build parameters) and then 3D print parts in different locations in the same metal 3D printing system or four companies in the same brand and model, the consistency would be challenged.The evidence suggests that “people in the loop” still have a big influence in digital manufacturing.
The global heat exchanger market is expected to grow to about $30 billion by 2026 from $18 billion in 2018 (Fortune Business Insight report).
Here are five ways to help increase the market for metal 3D printing:
1. Increase productivity.Laser-based metal 3D printers are still too slow and expensive.What is needed is a tenfold increase in productivity without increasing the cost of parts or machinery.
2. Improve the accuracy and resolution.Medium to large metal 3D printing systems that need to reduce the achievable minimum wall thickness by two to three times will open the door to new heat exchanger applications.
3. Develop new materials.Antimony is an ultra-light, high-strength, heat-conducting, corrosion-resistant material that can work continuously at high temperatures.
4. Prepare 3D printed heat exchanger standards.The creation and implementation of specific standards can assist in the identification and certification of heat exchangers.
Market education.The entire 3D printing circle needs to come together to educate the market and provide accurate information.