HOW TO Meet challenging requirements with high-precision sensors from Kistler

TSP Precision Tooling of Shanghai opts for quality assurance solutions by Kistler – not only for mold design, but also for its plastic processing operations. Cavity pressure sensor technology and the ComoNeo process monitoring system are the two cornerstones of zero-defect production, even when accuracy rates of just a few micrometers are required. 

China’s unparalleled economic upturn in recent decades is no secret, and the Far Eastern giant is already overtaking western countries in several sectors. Nevertheless, Chinese enterprises continue to be guided by successful models in Europe and overseas – especially in the mechanical engineering and industrial manufacturing sectors. TSP Precision Tooling (Shanghai) Co., Ltd., founded in 1999, is one such company. Mature technologies and the host of possibilities opened up by precision machining and manufacturing have made TSP one of the handful of Chinese mold providers to achieve certification to EU-TÜV 1699.

Thanks to a wide-ranging portfolio that includes mold design, development and production, TSP has gained the recognition and trust of an international customer base that focuses mainly on the automotive and electronics industries. The company maintains long-lasting business relationships with customers across the globe who benefit from its offering of top-quality “Kistler systems monitor our 24-hour manufacturing operations, and they record all the relevant data. What’s more, Kistler technology has helped us to integrate remote-controlled real-time monitoring and comprehensive, traceable documentation of our production data.” Huang Zhihua, Molding Test Supervisor at TSP molds and the high-precision parts that it manufactures. As a leading producer of both molds and injection-molded parts TSP undertakes to guarantee the quality of its precision manufactured products – so its customers are assured of critical competitive edge. However, this only holds true if the molds and parts meet each customer’s strict requirements for accuracy down to the last micrometer. 

High-precision sensors from Kistler meet customers’ challenging requirements Huang Zhihua, Molding Test Supervisor at TSP, reports: “As a supplier to the world’s leading manufacturers of fastening technology, we often get orders for molds that have to meet extremely demanding requirements. We use 3D models to design the molds according to the customers’ specifications, and then we carry out a test production run – that’s essential to ensure that the molded parts are free of defects.” Cavity pressure sensors and process monitoring systems from Kistler perform critical functions in TSP’s injection molding production operations. The Shanghai engineers have been working with Kistler since 2012, so they are familiar with the functions and characteristics of Kistler sensors. Thanks to this knowledge, they themselves are fully able to integrate the sensors into various molds. “Because of their wide measuring ranges and excellent reliability, cavity pressure sensors from Kistler can fulfill our very high requirements,” Huang comments. “We use them to test the quality of the design process for molds, and they also play a key part in our production lines: Kistler systems monitor our 24-hour manufacturing operations, and they record all the relevant data. What’s more, Kistler technology has helped us to integrate remote-controlled real-time monitoring and comprehensive, traceable documentation of our production data.”

ComoNeo cuts the short shot rate to zero

Incomplete part filling – the problem known as “short shots” – is one of the typical challenges that injection molders face. But with the ComoNeo process monitoring system from Kistler, short shots can be totally eliminated. “We start by determining the critical point of material shortage, based on the mold test curve and the DoE test (Design of Experiments),” Huang explains. “Next, we define the pressure value of the underfill curve according to the curve pressure at the critical point. Any underfilled parts are separated out at the same time, and then we check them with the help of the digital signal.”

The easy way to reproduce a tried-and-tested process 

Another ComoNeo function that is highly useful for TSP is ComoNeoRECOVER, the Restart Assistant. When a mold is switched from one machine to another, the parameters will change: for example, deviations may appear in the machine controlled curing process for the part. “But we can quickly restore the desired result by applying the cavity pressure reference curves that have already been saved,” Huang explains. “We use the ComoNeoRECOVER function to fine-tune the injection speed, holding pressure time and cooling period. While the process is being recovered, it’s important to stay as close as possible to the reference curve or, ideally, to follow it exactly.” This guarantees that the size and appearance of parts produced after the mold change will largely match the parts manufactured prior to the changeover. “By following these steps, we can establish a standard process that is optimally suited to mass production: we ensure that deviations are kept within a specified bandwidth, so the likelihood of faults occurring is minimized,” Huang continues. As another benefit, process monitoring with ComoNeo makes it possible to separate out any plastic parts that are beyond the tolerance interval. The result: all products that reach the conveyor and are ultimately packed in cartons for delivery will meet the zero defect requirement. For all these reasons, TSP is highly satisfied with Kistler: not only as regards solutions and service, but also in terms of the overall collaboration between the two companies. Huang Zhihua sums up: “Ever since we began working together, we’ve been able to count on vigorous support from Kistler’s engineers – across the board. As well as helping us to solve countless technical problems, they have played their part in training our engineers to achieve high standards of excellence. By acting consistently as a reliable partner, Kistler has substantially expanded our resources in R&D as well as design and production.”