Allot Tech
Liquid Filling Troubleshooting: Foam, Drips, Dose Errors and Line Faults
A filling-line defect can originate in the liquid, packaging, product feed, machine setting or downstream handling. Contain affected product first, preserve evidence and follow the symptom to a focused check. This guide connects quantity and liquid-control faults with handling, closure, labeling, cleaning and maintenance.
Choose a route from the observed defect
| Symptom | First evidence to preserve | Focused route |
|---|---|---|
| Foam or overflow | Where bubbles first appear, product temperature and settling time | Tank, feed and filling-profile comparison |
| Dripping or stringing | Closure timing, nozzle movement and contaminated surfaces | Valve, residual pressure and product cutoff |
| Underfill, overfill or variable doses | Head number, consecutive measurements and tank level | Measurement, bias, spread and supply drift |
| Jams, loose caps or wrinkled labels | Container lot, affected station and recent format change | Handling, closure or label-specific inspection |
Build a fault record before adjusting
- Record the exact defect, affected SKU, time, frequency, alarm and recent change. Keep photos or a safe observation video.
- Identify affected product and packaging for the site quality procedure; prevent suspect output from silently returning to saleable stock.
- Confirm the approved recipe, actual product condition, container lot and supply utilities. Distinguish one head from all heads.
- Make the equipment safe before inspection or opening. Follow the supplier procedure and site isolation rules.
- Change one variable, measure the result and retain the original setting. Repeat across the conditions that triggered the defect.
A fault record should lead to a decision
For a dose problem, record head, target, measured quantity, tare method, temperature, supply level, run state and out-of-limit count. For liquid cutoff, record where product remains, the closure and lift sequence, drops and neck contamination. For foam, include the first foaming location and settling time. This separates a measurement error, local branch problem and shared supply problem before parts are ordered.
Verify recovery beyond a few good bottles
The correction should survive startup, normal running, low product level, a production stop and the relevant format change. Retest dose, cleanliness, rejects and sustained good output together. Clear unresolved issues with evidence and update the controlled recipe or maintenance record. Do not bypass guards, inspection rejection or product-safety controls to achieve a higher apparent speed.
Handling, closure and operating guides
Use the finding when selecting equipment
For a new project, turn each failure mode into a specification: product behavior, compatible contact parts, filling range, package geometry, cleanability, measured good output and an acceptance method. For an existing machine, send the supplier the model, fault record and approved operating conditions. Allot Tech can help organize a China equipment sourcing brief; the final remedy and performance must be confirmed for the actual machine and product.