Flow optimisation in machines thanks to 3D printing

Like many other products, machines have to perform better all the time, while they also need to become more compact. Even though these two challenges are not easy to combine, they are often the goal in next-generation machine designs. 3D printing can be a solution thanks to the freedom of form this production technology allows for and also because it only builds up exactly what is needed.

Heat exchangers

A recurring example of where these two challenges coincide is the development of new generations of heat exchangers. The requirements of heat exchange are constantly increasing and preferably in the smallest possible space.

A good example is the heat exchanger developed by Sirris in cooperation with TNO. By using additive manufacturing both the weight and the volume were reduced by more than a factor 10. The performance was the same in this case, but the pressure drop over the heat exchanger was reduced by 90 percent. With less effort the same amount of heat can be exchanged with a very compacted heat exchanger.

A second recurring example is the use of 3D printing in the production of cooled mould inserts. These inserts, which may contain cooling channels right next to the hotspot or mould cavity to be cooled, are often quite a bit less complex and even more compact than when bores and stops are used.

A clear example is the case developed by Quadrant together with Sirris. By replacing four inserts in the relevant injection mould the cycle time was reduced from 50 seconds to 28 seconds (i.e. 43 percent profit). This is while keeping the dimensional tolerances and quality. The mould temperature also decreases significantly, from about 80°C to 40°C.

Case Quadrant: switch from conventional cooling channel to 3D-printed channel in mould insert

Injection nozzles

A third application where performance is combined with compactness is the 3D printing of injection nozzles. This area often makes use of the 'design-as-one-concept', in which complex assemblies are redesigned as one component. The nozzle channel is hereby redesigned to achieve an optimal shape for the required function and thus reducing the number of components. A beautiful example is the nozzle designed and produced by Melotte by order of Innogrind. The geometry/shape of cooling channels (diameter: 1.5 mm) is optimised for the process. In addition, also in terms of cost it is the cheapest production method.

Titanium Nozzle printed by Melotte by order of Innogrind

Valve blocks

A fourth application is the printing of valve blocks. In this case the design and production is quite a bit easier, because every connection uses only one channel and no longer a combination of drills and stops which have to be brought together. Thanks to the flowing channels the pressure fall is also reduced over each passage through the valve block, which results in a lower energy use in the application and less heavily dimensioned pump units.
A nice example is the illustration below in which a complex valve block with more than 100 drills was transferred into a 3D-printed block.

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