Bottles jamming at the star wheel? Find the cause yourself in 15 seconds
When bottles tip, jam or fall on a bottling line, most people call the technician first. Before you do, spend 15 seconds with your phone. Two times out of three, that is enough to find the cause yourself.
The slow-motion test
- Put your phone in slow motion.
- Film exactly where the problem happens, for 10-15 seconds, long enough for 6-7 bottles to pass.
- Watch the clip back slowly, bottle by bottle.
You do not need any special equipment. The clip shows what the eye misses at line speed: which bottle starts to tip, and where.
What you will usually find
It is usually one of three things:
- a star wheel of the wrong size, or one that is set wrong on its shaft,
- a setting that has drifted and needs adjusting,
- an infeed screw that needs to lead or lag to stay in sync with the star wheels.
A star wheel has to be adjusted on its shaft so that it stays in sync with the other parts of the machine. When it is not, the bottle arrives at the pocket at the wrong moment and the line stops.
When it only jams at full speed
A fit that looks perfect with one sample bottle can fail when a full line of bottles pushes together. We once ran a set 2-3 mm tighter than a conventional star wheel. With one bottle on the machine everything ran. With a full line, the machine stopped 5-6 times on jams.
So test with several bottles from the real batch, not just one, and film that test too.
If you cannot see the cause
Send us the clip, the machine model and the bottle diameter. We cannot tell without seeing it, but a clip is usually enough to say which of the above it looks like. If a new gripper or a different fit is the answer, we make it in 3-5 working days. If it is a setting, we tell you that too.
Frequently asked questions
Why do bottles jam at a star wheel?
Most often because of a star wheel of the wrong size or set wrong on its shaft, a setting that has drifted, or an infeed screw that is out of sync with the star wheels.
How do I find the cause of a bottling line jam?
Film the problem spot in slow motion for 10-15 seconds, long enough for 6-7 bottles to pass, and watch it back bottle by bottle. Two times out of three you will find the cause yourself.
Why does the line jam only at full speed?
A tight fit can work with one sample bottle and fail when many bottles push together. Test with several bottles from the real batch before you commit to a set.
Can you diagnose a jam from a video?
Usually enough to say what it looks like. Send the clip with the machine model and the bottle diameter and we will tell you which cause it seems to be.
Want us to look at your clip?
Send us the video, or book a free 30-minute call. There is no commitment.