Seal Position Problems

Problem

Finished packages show the end seal landing too near the product, leaving excessive film on one side, or the seal point varies package to package. Cut quality may be normal while the seal position alone is off.

Possible Causes

1. Jaw timing (phase) does not match the current format or recipe.
2. Recipe length values do not match the product and film mounted.
3. Product pitch drifts at speed, moving the product within the wrap.
4. Film feed inconsistency shifts the web relative to the cycle.
5. Registration corrections interact with the seal position when the print layout changes.

What to Check

• STEP 1Measure the seal position on samples.Measure several consecutive packages — constant offset points to setup, variation points to drift.
• STEP 2Verify recipe values.Confirm the loaded recipe matches the product, film and format actually on the machine.
• STEP 3Check pitch stability.Observe product spacing at production speed for drift or bunching.
• STEP 4Observe film feed consistency.Watch for slip or variation at the feed rollers (see package length checks).
• STEP 5Review registration influence.If the film print layout changed, confirm registration setup matches the new layout.

Corrective Actions

• Re-establish jaw timing per the machine manual and store the verified values in the recipe.
• Correct recipe length values and re-qualify with sample packages.
• Resolve pitch drift via the feeding checks before adjusting sealing.
• After any film print layout change, re-run the registration setup.