When to Optimize the Rear Zone

The optimal rear zone temperature is specific to each machine and material combination. For this reason, a rear zone temperature study should be performed each time a new material is molded on a particular machine. 

Question: In my case we have machines from different brand, so a study in the rear zone temperature must be performed. So, in a situation like that, how do we perform that study? Under which conditions could we perform the procedure?
My Response: Since the rear zone temperature has no significant affect on the polymer melt, the following test can be performed during production. This can allow you to adequate time to allow the rear temperature zone to stabilize and obtain excellent results.
Rear Zone Temperature Study Procedure:
  1. Set the molding machine to manufacture stable product
  2. Set the rear zone temperature to the manufacturers recommended minimum
  3. Allow the rear temperature to stabilize
  4. Record the ‘Rear Zone Temperature’ and the ‘Recovery Time’
  5. Increase the rear zone temperature incrementally
  6. Repeat steps 3-5, but do not exceed the manufacturer’s recommended maximum
  7. Graph the data: Time (Y axis) vs. Temperature (X axis)
  8. Evaluate the graph and select a temperature with a low recovery time 

-Andy

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