Tension regulation is indeed related to the length of the transmission chain, but they are two different concepts.

A longish transmission chain doesn’t mean they lack of tension, but people are usually don’t want to see the sag of the chain. Actually, the tension will be reasonable if the chain can engage with the sprocket’s teeth well and can afford the load successfully.


According to the above drawing, even 80 mm difference in sag will only reduce 1.5 teeth’engagement, so the length of chain is not key factor of tension.

However, overlong chain will impact on the the engagement and brings insufficient wrapping angle, under this case it is necessary to shorten the chain properly.

chain sag

As shown above, the maximum Sag we advise is 150mm , please shorten the chain and keep the sag less than 90mm.

How to measure the sag of chain?

Measurement of Sag

In theory, slat chain should run horizontally if without support when spiral conveyor in operation, however, because of traction generated by the bearings at bottom of slat chain, the chain in sag position actually move with inclined angle, so point A should be taken as reference point when measuring the depth of sag.