The lay-out of the HPDC process itself was especially demanding. Comparable and reliable results for possible combinations of design and casting parameters had to be available very early. Axel Schmidt, leader of the project management with DGS, remembers the most critical questions: "Can this casting, with flow lengths of several meters, be completely filled at all? Which filling time is necessary for a complete filling? What happens if filling fronts meet after 2 to 3 meters of melt flow? How big are the length variations and how much does the massive gating pull the frame apart? We had to answer all these questions very early to work in a cost and resource efficient manner and to lead the project to a success". At the beginning, a design with two gating areas was developed and evaluated with MAGMA5, looking at different quality criteria such as ‘Flow-Length‘‚ ‘Fill Temperature‘ and ‘Material Trace‘. As it turned out, solving the problem of frame distortion was the most challenging task.
The first simulation results indicated frame distortion values of up to 9 mm lengthways and 5 mm crossways for the initial gating design - results far from the customer specification. The situation was so severe that a complete redesign of the gating system was the only proper answer possible for the DGS-team. The experts checked further experience-based alternatives, again using MAGMASOFT®. According to DGS, MAGMA5 was a key factor to comply with the timeline and secure the success of the production process at the same time.
The solution was eventually successfully identified: a system with gating areas in all four corners and a total of 20 ingates. Axel Schmidt recapitulates: "To develop the design with minimized frame distortion, MAGMA5 played a crucial role. The possibility to quickly and early test different variations was essential, allowing us to create the gating system in a way that it exercises as little force on the casting as possible. This way we could actually completely avoid any critical distortion and minimize other casting related defects at the same time. The ‘Material Trace’ results allowed us to check the symmetric flow of the melt. And of course, the ‘Distortion‘ result was used to analyze the warping of the part in great detail and document and discuss the effects of every design modification".
Next, the fixed casting lay-out had to be transferred to the conditions of the production environment. The design and placement of the die inserts and the cooling lines were the pending major tasks. Again, the DGS team used MAGMA5 to develop the cooling of the 10-fold divided die halves. Two die halves weighing 14.1 and 20.3 tons, optimized with regard to the especially demanding casting dimensions and cooling requirements, were the final result. The die was cleared for manufacturing and the production could eventually launch on time. Today, the final product is an integral part of two different solar collectors of leading manufacturers.