1. Keep the evidence before changing the recipe
Retain examples of both the unexpected result and a known acceptable result, if available. Label the samples with the time, material lots, machine or station, and recipe reference. Photograph the unopened pack before opening it for inspection.
Follow your site's procedure for holding affected production. Equipment checks, cleaning and adjustments should follow the machine manual and be handled by trained personnel. Keep the quality decision separate from the troubleshooting trial.
A better starting questionInstead of “Which setting should we increase?”, ask “What differs between the good and affected packs, and how can we check that difference?”
2. Describe the pattern precisely
“Bad seal” can mean several things: a visible gap, a wrinkle, a changed opening feel, damage to the pack, or a failed inspection result. Record the observation without turning it into a diagnosis.
| What you observe | Useful comparison | Evidence to retain |
|---|---|---|
| The same area looks different | Does it follow the container orientation or a particular tooling position? | Marked photos showing pack and station orientation. |
| The change began during a run | What happened immediately beforehand: a material change, stoppage, restart or adjustment? | A timeline with recipe and lot references. |
| Only one format is affected | What changes with that format: container, closure, supports or recipe? | Side-by-side format and changeover records. |
| The appearance passes, another check fails | Were the same test method, conditions and acceptance limits used? | Original inspection results and the test procedure. |
A pattern can narrow the next check. It does not prove a root cause on its own.
3. Separate the investigation into three groups
Material and pack
Compare the container and closure references against the approved baseline. Include lot changes, supplier documents, visible damage and rim condition. Confirm that a substitute material was actually qualified for this pack rather than accepted because it looked similar.
Position and contact
Record how the pack sits in its fixture or travels through the station. If a result varies by location, preserve that location in the record. Ask the equipment supplier which alignment or contact checks are appropriate for the installed machine.
Process and sequence
Record the settings and actual observations available from the equipment. Note start-up, pauses, changeovers and the point in the run where samples were taken. Confirm the meaning of each displayed value from the machine documentation.
The process route matters here. A direct heat-press station and an induction foil sealer do not use an interchangeable troubleshooting recipe. Identify the actual process before requesting settings advice.
4. Make the next trial traceable
Agree on a safe trial with the responsible operator and supplier. State the hypothesis, the permitted change, the samples to use and the result to measure. Avoid changing several unrelated factors together; the result then becomes difficult to interpret.
Use the same inspection procedure before and after the change. Retain the measurements and unsuccessful results as well as the samples that look promising. A short successful run is evidence from that trial, not automatic approval for all materials and shifts.
A compact trial record
- Trial ID, date and responsible person
- Container, film or liner reference and lot
- Machine, tooling position and recipe reference
- Observed problem and comparison sample
- One stated change and the reason for it
- Sample count, test method and recorded results
- Decision, remaining questions and next owner
5. Send a review package that can be used
Group the marked photos, timeline and trial record in one enquiry. Include the machine identity, installed configuration, material specifications and your acceptance method. Identify whether you need help with the existing setup, a new material trial or an equipment change.
For tray projects, state whether the issue concerns the seal itself or a separate atmosphere measurement. Keep those observations distinct when discussing MAP tray equipment.
Contact Yijia Packaging through Sealerweb for an equipment and sample discussion. Explain the evidence first, then list the questions you want the supplier to help resolve.
Scope and equipment references
This is an investigation worksheet, not a machine adjustment procedure or a diagnosis of a specific defect. Related equipment and sample-enquiry pages were checked on Sealerweb on 9 September 2026. Use the installed machine's manual and your approved quality procedures for actual trials and product release.