How can thickness fluctuations be avoided in machine direction?

This fault points to various possible causes:

1. Insufficient roll pressure

Remedy:
Increase contact pressure of calender rolls

2. Pronounced fluctuations in melt temperature

Remedy:
Check barrel temperatures for fluctuation

3. Take-off is irregular

Remedy:
Check take-off speed

4. Fluctuations in feed

Remedy:
See section "How can fluctuations in feed be avoided?"

5. Inadequate back pressure

Remedy:
Install restrictor bar or throttle valve

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