A Tech Bite from Greener Technical Service Specialist Jeff Fouche
It can be difficult to determine the cause of intermittent cutting and sealing problems on flow wrappers. Issues may occur on two or three packages and then resolve, only to continually repeat at random intervals—perhaps in five minutes, then after twenty packages, and again an hour later.
This Greener Tech Bite explains how to diagnose and fix intermittent cutting and sealing problems on flow wrappers caused by worn bearings and other factors.
Severely Worn Bearings
Severe bearing wear causes cutting and sealing problems that are consistent, not intermittent. This severe wear allows movement in the shafts that you can feel when you tightly grip and push them up and down or side to side.
Uneven, Less Severe Bearing Wear
When bearings wear unevenly and develop random flat spots, you won’t be able to feel the shafts wiggle. Determining if this less severe bearing wear is creating your intermittent cutting and sealing problems requires the process of elimination—you will first need to rule out three other possible causes:
Worn Gears
Backlash
Misaligned Sealing Jaws
Worn Bearings
1. Worn Gears
To start, visually inspect the gears and replace them if they are worn. Worn gears mesh inconsistently and can cause poor seal quality and incomplete cuts at random intervals, especially when the wear is uneven.
Learn more from our post and video on the effects of worn gears.
2. Backlash
Also inspect for and remove backlash, or independent rotational movement between the upper and lower sealing jaws. Backlash causes intermittent cutting and sealing problems by allowing the knife to swipe across or leave multiple impressions on the anvil and by misaligning the serrations.
Visit our post and video about diagnosing and adjusting backlash on flow wrappers for more details.
3. Misaligned Sealing Jaws
Once backlash has been removed, the sealing jaws may still be misaligned. Run a carbon impression and check the alignment of the serrations. Misaligned jaws wear unevenly and cause intermittent problems when they don’t mesh properly.
Consult our Tech Bite on diagnosing sealing jaw misalignment with carbon impressions for more information.
4. Worn Bearings
If intermittent problems persist after you check and correct the first three issues, then your bearing are worn and should be replaced.
There is no reliable way to determine which bearings are bad, so when you invest the time to access the bearings you should replace all four of them.
The new bearings should eliminate your intermittent cutting and sealing problems.
If you would like to improve the forming, cutting, and sealing performance on your flow wrappers and vertical baggers, connect with Greener Corporation’s technical experts.
We provide integrated parts and technical service solutions worldwide.
