Bottle inspection after washing.
Inspection closes the bottle washing process. The site should define which conditions are checked, where the check occurs, how failures are rejected and what evidence releases bottles to filling.
Inspect at the point that represents the next operation.
A bottle can appear acceptable at the washer outlet but change during accumulation: water can drain, condensation can form, dust can settle or labels can be applied before an external surface is ready. Locate the inspection and acceptance time so that it reflects the actual downstream risk.
| Inspection category | Examples of checks | Important limitation |
|---|---|---|
| Visible internal residue | Film, particles, sediment, foreign objects, neck/base pockets | Coloured or shaped bottles can limit visibility; visual inspection cannot prove every chemical residue absent |
| External residue | Soil, adhesive, label fragments, scuffs and spotting | Cosmetic acceptance should be separated from functional cleanliness |
| Residual chemistry | Method appropriate to the chemistry, such as conductivity, pH or a validated analytical/swab method | The competent process/quality team must select and validate the method and limits |
| Moisture | Internal droplets, external wetting, base/shoulder pockets and timed drain condition | Acceptance depends on filling, labelling, coding, inspection and storage requirements |
| Damage | Chips, cracks, scratches, deformation, neck finish and base stability | Pre-existing damage should be recorded so process-created damage can be distinguished |
| Label/adhesive | Residual face stock, glue area, fragments and transfer to guides/filters | A de-labelled bottle may still require a validated adhesive-removal wash |
Manual inspection design
- Defined lighting and background
- Safe handling and ergonomic reach
- Known sample frequency and reject categories
- Examples or photographs of pass/fail defects
- Segregated reject container and traceability
- Training and periodic consistency checks
Automated inspection questions
- Which defect is visible to the sensor/camera?
- Does bottle colour, embossing or moisture affect detection?
- What triggers the reject and how is it confirmed?
- How are false accepts and false rejects challenged?
- What happens during downstream blockage or reject-bin full?
- How is the system cleaned and rechecked after changeover?
Create a release and escalation rule.
Define who can release bottles after a normal run, what deviation blocks release, how affected bottles are segregated and what repeat check closes the deviation. A recurring defect should feed back to process settings, maintenance and incoming-bottle controls rather than being managed only through more inspection.
Post-wash acceptance record
- Bottle family and batch/return source
- Washer configuration and operating condition
- Inspection location and time after discharge
- Sample quantity and method
- Defects by category and reject rate
- Any rework, adjustment or deviation
- Release decision and responsible person
Use the validation guide for method development, the FAT guide for machine testing and the troubleshooting guide when results drift.
Define the inspection boundary with the machine brief.
Send the bottle type, defects to detect, required moisture condition, inspection method and reject requirement.
Discuss bottle washing and inspection