How do I get a reliable seal on a centre-seal bag?
Keep product and dust out of the seal area, control the material path and apply the approved time, temperature and pressure window. The seal construction must be compatible with the centre-seal bag and its product.
What should I check first?
Record the machine state and the finished result before changing settings. This helps identify where control is first being lost.
- Inspect stored and machine-fed centre-seal bag for the longitudinal seal sits on the back of a formed pillow pack.
- Observe every stage of vertical form-fill-seal.
- Check pickup, opening, fill, settling and seal timing separately.
- Verify pouch or rollstock dimensions, structure, seal layer and production tolerances.
- Observe pickup, opening, filling and sealing as separate stages.
- Run the lightest, dustiest, most static or most irregular product.
Why is this production problem happening?
Work from the evidence and change one variable at a time. These are the most relevant causes to investigate first.
- Pack material condition or tolerance prevents repeatable handling.
- The product discharge contaminates or deforms the seal area.
- One retry or reject state is not correctly sequenced.
- Flexible material quality or storage condition is inconsistent.
- The dosing discharge is not coordinated with pack opening and settling.
- Film or pouch handling geometry is incorrect for the format.
How can I correct or improve it?
Make a controlled change, repeat the same measurement and compare the result before moving to the next adjustment.
- Trial full production rolls or pouch batches.
- Add confirmation sensing at the process step that can fail.
- Set measurable dose, seal and output acceptance criteria.
- Control pouch or film specifications and storage.
- Reduce uncontrolled product fall and protect the seal area.
- Tune handling first, then dosing, then sealing.
What should I send Lancing?
The most reliable recommendation is based on representative production materials and a measurable acceptance result.
- At least two normal batches of centre-seal bag materials
- Product sample and dose range
- Seal specification and acceptance method
- Artwork and code position
- Required good output
- Production pouches or rollstock and technical specification
- Product sample and flow, dust or stringing behaviour
Which applications does this answer cover?
More quick answers about this problem
What should I check first for centre-seal bag?+
Inspect stored and machine-fed centre-seal bag for the longitudinal seal sits on the back of a formed pillow pack.
Why does this problem happen with centre-seal bag?+
Pack material condition or tolerance prevents repeatable handling.
How can I improve or correct the problem with centre-seal bag?+
Trial full production rolls or pouch batches.
Which part of the production line does this question relate to?+
This question relates primarily to pouches, sachets & form-fill-seal. It may also be affected by upstream product or pack supply and by downstream handling, so check the full production sequence rather than one machine in isolation.
What should I send when asking for a machinery recommendation?+
Send At least two normal batches of centre-seal bag materials; Product sample and dose range; Seal specification and acceptance method; Artwork and code position. Representative production samples and a measurable acceptance target are normally more useful than a catalogue description alone.
Explore the relevant Lancing machinery options
Review suitable equipment and application guidance, then request a recommendation based on your product, pack and required accepted output.
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