TL;DR
Stopper insertion faults are usually a stopper bowl jam, a worn insertion finger, or a stopper that is too sticky or too hard for the inserter setting. Check the bowl and insertion force first.
What you might see
- stopper missing in sealed vials
- stopper insertion station alarm
- stopper double-feed from the bowl
- stopper skew or tilt after insertion
Likely causes
Stopper bowl electrostatic jam from low-humidity conditions in the cleanroom
Stopper lot hardness or geometry variation outside the inserter tolerance
Worn or bent insertion finger causing skewed placement
Stopper guide track contaminated with silicone coating buildup
Required tools
- Shore A durometer for stopper hardness
- Stopper dimension gauges
- Approved cleaning agent for track
- Replacement insertion finger
Safety first
- Follow cleanroom gowning protocol throughout. Any contact with the sterile vials or stopper feed path without proper gowning is a contamination event.
- Stoppers intended for injectable products are high-risk components. Segregate and quarantine any stoppers that have fallen to the floor or been touched with ungloved hands.
Procedure
- 1
Stop the line and clear the stopper fault from the controller.
- 2
Inspect the stopper bowl and feed track for bridged or jammed stoppers. Clear the jam and check the bowl vibration amplitude setting.[1]
- 3
Measure the stopper hardness (Shore A) and dimensions and compare to the certificate of conformance for the current stopper lot.
- 4
Inspect the insertion finger and head for wear, deformation, or silicone residue. Clean or replace as needed.
- 5
Check the stopper guide track for residue buildup. Clean with the approved cleaning agent for the track material.[1]
- 6
If the humidity in the cleanroom is low, confirm the humidification system is operating. Stoppers are prone to static issues below 45% relative humidity.
- 7
Run 20 vials through the insertion station and inspect each stopper for correct seating depth and absence of tilt.
Sources
Bosch / Syntegon Syntegon FXS / FLS Vial / Syringe Filling Line general technical documentation, Bosch / Syntegon
Syntegon FXS / FLS filling line general stopper insertion and handling procedures (general)
More guides for Bosch / Syntegon Syntegon FXS / FLS
How to fix fill volume deviation on a Syntegon FXS / FLS vial filling line
Fill volume deviation is usually a worn pump piston, a leaking check valve, or a fill needle tip blocked with product. Check and recalibrate the fill pump and valves first.
How to fix vial breakage on the conveyor of a Syntegon FXS / FLS filling line
Vial breakage is usually a conveyor belt misalignment, a guide rail set too narrow, or a vial handling star wheel timing fault. Check guide rail spacing and star wheel timing first.
Stop fixing the same fault twice.
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