The traditional approach is to decide on the concept for the part and the mold, drawing on experience and possibly
availing of mold-filling simulations. The mold is then fabricated and machine-tested. This usually marks the start of an iterative process for sizing the gate and finalizing the process parameters, as well as eradicating any manufacturing flaws. Although this process can take several weeks, pressure to start production is often the factor determining which process window should be used. That process window is often far away from the mold’s
optimal operating point, though. Sigmasoft Virtual Molding adopts the exact opposite approach: performing the
iterative process at the start of the design process and before the mold is made. Nowadays, simulations can be performed so quickly that the design and production conditions for a complete mold can be determined in just two to four days, during which time the relationships can be understood and the correct processing point for a part identified.
Early adopters of this virtual technology report that this has given them a “new understanding” of the injection molding process. This understanding inspires confidence in toolmakers and converters by providing a sound basis for their decision-making that will simplify and speed up the design of future molds.
Virtual Injection Molding as a Core Technology
Kalypso Ultra Technologies Inc., based in Ottawa, Ohio, USA, specializes both in product and mold development and in the use of DMLS (direct metal laser sintering) and additive manufacturing to optimize thermoplastic applications and specialist processes, such as LSR, metal and micro-injection molding. This leads to enhanced design flexibility, particularly in the integration of conformal cooling concepts. What sets Kalypso apart is its integrated approach, consisting in the use of photorealistic models, 3-D-printed part designs and informative “full motion” simulations to perform detail modeling and to provide advance insights into the entire process. It summarizes these results on information sheets for use by process setup. The converter can thus be confident that parts will be made flawlessly, regardless of product complexity.
Shawn Schnee, Managing Director of Kalypso, is a plastics engineer with more than 20 years’ experience in the industry. After several unsuccessful attempts, he was about to give up on injection molding simulations and revert to trial and error. However, he reconsidered when he learned of Sigmasoft’s Virtual Molding
technology, and decided to give computer-assisted analysis another chance.
Today, Kalypso deploys virtual injection molding as a core technology because it is capable of accurately simulating the various relations existing between the key factors involved in injection molding. The entire process is reproduced over several cycles, allowing the performance of the proposed mold parts to be analyzed in a production window – much as if the machine itself had been used, but without the outlay entailed in making the actual mold.
Kalypso uses Sigmasoft Virtual Molding to design and coordinate the various parts of new molds. The company’s specialists plug in all the physical properties, material properties and process interactions, so that they can analyze the relationships between the cooling circuits, hot runner system and thermocouples in advance. Schnee says that to neglect any one of these critical variables is to run the risk of costly mistakes and weaken the accuracy of the computer-assisted analysis.