Should the cap feeder stop as soon as the capper stops?
Not necessarily every feeder stage must stop at the same instant. The control may allow a short, stable final queue to fill before stopping upstream supply, or it may stop immediately when the cap or chute cannot tolerate further accumulation.
The intended behaviour should be defined from the track capacity, closure condition, capper stop pattern and control architecture, then tested during normal pauses and faults.
Relate stopping to buffer capacityHow is a full chute detected?
A suitable sensor can monitor cap presence or queue level at a position chosen to represent the usable final buffer. The sensing method depends on cap material, colour, geometry, spacing and the physical access around the track.
The sensor position must allow enough time for upstream stages to stop before the queue becomes unstable. The trial should check false detection, gaps between caps and restart as the queue falls.
Review cap-in-chute sensingWhat prevents caps being damaged during a prolonged stop?
Upstream supply should stop before excessive queue pressure or recirculation develops, while sensitive caps remain within the stable part of the route. For a long stop, the operating instructions may require additional clearing or isolation depending on the cap and machine.
The acceptance test should inspect queued and recirculated caps after representative stops, especially when liners, tamper bands or decorated surfaces could be affected.
Check sensitive closure conditionsWhat should operators check before restarting?
Operators should confirm the cause is cleared, guards and access points are restored, the chute or pick point contains correctly presented caps, sensors show the expected state and the capper is ready to receive closures. The final sequence must follow the machine instructions and site safety system.
A documented first-off check can confirm cap presence and application after restart before the line returns to normal production.
Include restart in acceptance testing