Styrolution's technical team had done a trial run on 15-15 July 15 by reducing a holding pressure and holding time about 1.5 days. The purpose is to reduce excessive stress on injected part caused by over packing. The holding pressure and time was max decrease until the sink mark was not acceptable by customer. The process conditions before & after adjustment and reject rate (crack) were shown in Table no.2. lt seems that the reject rate between before and after adjustment is not significantly different.