Die Commissioning Process

1. Use short die installation procedures to set die to die stand
2. Make sure all heater bands are working properly and install temporary heater bands
3. Heat up die to running temperatures
4. Once at running temperature, heat soak for 2 hours
5. Leave temporary heater bands in place and fill outer wall caliper first by
   1. Turn on extruder at low rpms (2 – 3 rpms) and low pressure to fill the die tool

      

   2. Periodically check that pressures in the die are not building by turning the speed pot down and checking for the pressure to drop.
      1. If the pressures come down then everything is fine
      2. If the pressures do not drop with a speed pot reduction, stop flow immediately and shut down the process and begin troubleshooting
         1. This is indication of an issue that the die
            1. May be too cold
            2. There is a something inside the die that is not working properly
            3. The die gaps are too tight (only indication if the material is at the caliper)
   3. Once the material reaches the caliper, check for a roughly even flow around the caliper and that no voids are present.
   4. Clean material off die and repeat steps for inner wall

Notes:

1. The die gaps come preset. The inner die gap is set to the specified inner wall thickness. The outer die gap is set to 1.5 times the outer wall thickness requirements (this gives space for corrugation forming in the molds.
2. As the die fills for the first time there will be fluctuations in pressure as the material moves and fills the spaces within the tool. This will create gradual pressure changes and the material flows. Watch for rapid, continual increases in pressure and if pressure doesn’t drop with speed pot reductions.