Go with the highest number…
Go with the highest number of 3% of your center to center distance as it sounds like you have a polyester/nylon belt (based on your selection of 3% in the first chart) that type of belt will have a lot of permanent elongation vs an all polyester carcass. The longer you make the screw take-up travel the least likely you will need to resplice as the permanent elongation reduces. This type of belt will need constant attention to the screw take-up on a daily basis until you fully stretch the belt to prevent drive slippage.
The second chart takes into consideration that you have a mechanical splice and would be able to resplice before the permanent elongation is removed. That is why the larger value for a vulcanized splice that you do not want to have to resplice.
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Gary Blenkhorn
President - Bulk Handlng Technology Inc.
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Screw takeup systems
Hello
I have a question about screw take up system and need help for calculation travel distance of screw take up.
Iam designing a shuttle conveyor with 42 m length.
According to attached pictures of cema standard, 2 tables submitted for travel distance of screw takeup. In first table, mentioned travel distance is 3 % of center to center for 75% of rated tension. And in second table it is 1.75% for center to center distance in 75% of rated tension and for polyester wrap. What's difference between these tables?
Also in rule of thumb calculation it is 1.5% of tail and head center to center distance.
Iam confused. Which one is correct?
For 42 m c-c length, traveling distance of screw is 1260 mm or 630 mm ?
Thanks
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