Power Up of Extruders/PLC - Wheel Blow Molder

Following is a extruder startup procedure for a wheel blow molding machine:

1. Turn on the plant chilled or tower water supply to the extruder heat exchanger and extruder feedthroat.
2. Turn on the power at the PLC wheel drive cabinet by raising up the handle in the top right corner. An audible alarm will sound.
3. Push the reset button that is located in the middle of the cabinet door. The button will illuminate.
4. Go to the PLC monitor and wait momentarily for the computer to boot up.
5. Press the ACK and the RESET touch button on the screen . This will silence the alarm.
6. Press the touch button that reads HYD. WATER HEATS in the lower left corner. A start screen will appear.
7. Press the start touch buttons for the pump heats only.
8. Press the MAIN touch button in the top right corner to return to the main screen.
9. Verify that the green lights below the water and heats label on the screen are illuminated. This indicates an “on” condition.
10. Press each individual extruder touch button located in the top right corner of the main screen to access each extruder screen one at a time. Press the AMP on/off touch button in the lower left corner of the extruder screen to observe the current draw.
11. Repeat the above instruction for each extruder to check current draw for each zone.
12. Push the Main touch button to return to the main screen.
13. Wait for a minimum of two (2) hours for the heats to arrive at their set points and soak.
14. After the heats have reached their setpoints and sufficient soak time has expired the extruders can be started.
15. Press the HYD WATER HEATS touch button in the lower left corner of the main screen. The start screen will appear.
16. Press the START touch button for the hydraulic pump. The pump will start momentarily.
17. Return to the main screen by pressing the MAIN touch button.
18. Press each individual extruder touch button located in the top right hand corner of the main screen to access each extruder one at a time. Press the ON touch button directly under the enable label to enable that extruder.
19. Go to the main screen by again pressing the MAIN touch button in the top right corner.
20. Repeat this enabling process for each extruder.
21. Check all heats once again.
22. Go to the main screen and press the EXTRUDERS touch button to initiate. The main speed control potentiometer must be at the zero (0) setting.
23. At this time proper face shields and gloves must be worn.
24. Slowly rotate the main speed pot to the #20 position closely observing the extruder amps and PSI for each extruder. Note: Quickly rotate the main speed potentiometer to the “0” position at the first indication of high amps or PSI while keeping the maximum extruder pressure under 6,000 PSI.
25. Increase extruder speeds by turning the pot to #100 (100% extruder speed) and purge for 30 seconds or until all entrained air in the plastic is removed.
26. Stop extruding by rotating the speed potentiometer to #0 position.

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