Page 86 - Injection Molding Advanced Troubleshooting Guide
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70    8 Machine Performance




               This method will show a wide variety of odd machine characteristics that may need
               to be dealt with from a maintenance standpoint. Figure 8.9 shows a machine with
               terrible second-stage pressure tuning. Greater access to data will help understand
               if a machine is performing reliably.


































                                 ®
               Figure 8.9  RJG eDART  data showing oscillation of hold pressure





               „  „8.5„ Cycle Variation


               Letting the process run in a steady-state operation for a given period of time gives
               good insight into the consistency of the molding machine. Many factors can be
               checked for variation over time including:
                  ƒ Fill time
                  ƒ Shot size
                  ƒ Transfer position
                  ƒ Second-stage pressure
                  ƒ Clamp open position
                  ƒ Eject forward position (critical for robotic part removal)
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