The industry is in the midst of a huge transitional phase, and as new challenges arise in the development of hybrid and battery electric vehicles (BEVs), the advantages of LSR and TPL come into their own. Not only do they offer outstanding electrical properties, but they are also resistant to ozone, weather and UV rays and offer excellent temperature resistance on both the low and high ends of the scale. Critically, they also enable the integration of functionality, good bonding and the ability to deliver even the most complex multi-part geometries.
Of course, none of this is possible without the correct tooling - the creation of which can be very complex. This is why we at Datwyler have kept the entire process in-house in order to exercise complete control over the end result which enables a high customer satisfaction. Our 900m² state-of-the-art tooling center, located in Cleebronn, Germany, enables us to develop highly customized, customer-specific tool concepts that meet the highest quality standards in complex and system-critical part geometries. This, coupled with over 30 years of experience in tool manufacturing, guarantees high precision, fast development speeds and unprecedented levels of flexibility and versatility.
Capabilities under one roof ensures highest quality
At Datwyler, our people are already highly experienced, but their continued development is paramount. Therefore, we have a training program that is ongoing to ensure the tasks associated with tool building are always at the cutting-edge. In addition, the elements that comprise the process are also proprietary. To manufacture tooling for complex part geometries we use sink and wire erosion processes. The graphite electrodes for the sink erosion process, that we manufacture internally, ensure the highest accuracy of dimensions and tolerances.
This is key, as ultimately the tools we create for LSR and TPL are part of a process that is carried out without material waste. Manufacturing therefore relies on the process being optimal. It is crucial that we can guarantee that the tooling is correct to ensure a zero waste process and to meet the product tolerances required, which takes multiple steps. Usually you make a tool, manufacture a certain number of parts and then correct the tool, which can be time consuming and thus leads to delays.
By having the capabilities entirely in-house, we are able to do the molding internally and also the correction of the tool, which reduces the time for correction loops significantly.
The fewer adjustments required the better, as the process is then faster. That is where experience is vital, especially for new parts, where you run the tool on the machine for the first time. It is key to use the correct settings and to analyze the results in order to make the necessary changes and to achieve the desired end results. For this we use the first-of-tool (FOT) parts process, making the tool slightly smaller in the first instance and then recorrecting the mold by removing material to ensure the optimal size.
In addition, we are able to take full advantage of our in-house simulation capabilities, using mold flow technology to simulate the material’s behavior during the injection molding process to help achieve the most accurate first design. It is not possible to make a tool to exact tolerances without a first trial, but we can get close through these simulations in order to further reduce correction loops.
Own the process, own the end result
In terms of the process of manufacturing the tooling, the base frame of the tooling is created by cutting process. In a next step, the tool parts that create the geometry of the part are most of the time created using an erosion process. This requires electrodes , as we mentioned earlier, which we manufacture internally out of graphite using high speed cutting. Once we have made these electrodes, we apply our sink or wire erosion capabilities that enable us to create the very precise geometry of the tool parts – the tool inserts. These inserts are assembled into the base tooling to create the finished part geometry.
Finally, the injection molding process for LSR uses a cold runner system. The valve gated cold runner system allows us to inject directly on the surface of the part without any flash or material waste.
Of course, parts can also be injected with a sprue, meaning every injection point connects multiple parts, creating even higher cavity densities. The cold runner system was also developed in-house, due to the fact that it is such an important element in creating a high quality part.
Having all of these capabilities in-house enables us to offer the flexibility customers need to deliver consistent quality around the world. Tools that are approved to make series production parts are manufactured in our competence center in Germany and then transferred to our global LSR/TPL production sites, in China and in Mexico. With this we ensure that wherever a Datwyler part is required it has the same high quality across the board.