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Calculation of Load on Centre Idler Roll

Calculation of Load on Centre Idler Roll

Calculation of Load on Centre Idler Roll

Hi All,

Recently moving from the O&G industry into mining, so I have never done any calcs on conveyors / idlers.

I require some help with calculating the load on a centre roll of a suspended, 3 roll idler set. The reason why I want to do this is because I notice there is significant length of free belt between the suspended idlers and and the next carry idler along the conveyor.

70% of total load on the centre roll
Friction = 0.9
Idlers have 45 deg trough angle

Some numbers I have:
belt running at fully loaded case: Q = 15,000 tph
Belt speed: v = 5.5 m/s
Belt tension: T = 520kN
Belt Mass: M = 80 kg/m

Distances between Suspended (Idler1) and inline (Idler2):
Vertical: Z = 0.382 m
Horizontal: X = 3.798 m
Distance centre-centre: 3.818 m

If someone could help me out / point me in the right direction, that would be greatly appreciated.

Thank you

RE: Calculation of Load on Centre Idler Roll

Cant help you with the calculations but the following may be usefull. There do exist a number of useful conveyor engineering text books, mostly published 30-40 years ago. A used book search might help.

At 15000 tph this is not a small operation. I would think the systems were designed by very experienced competant personnel. What is that you observe that causes you to think there might be a problem.? A certain amount of belt sag is normal, the amount of sag is dependent on distance from the loading point. This is what take up pulleys are used to compensate for.. Your belt suppliers would probably welcome an opportunity to help with this.

RE: Calculation of Load on Centre Idler Roll

This is a very quiet forum. You may get better traction posting on the mechanical engineering general forum.

Not quute sure what your question is though.

Drawings or sketched help a lot to understand.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Calculation of Load on Centre Idler Roll

Thank you both for your input.

I will try the Mech engineering general forum as you have suggested.

RE: Calculation of Load on Centre Idler Roll

Hi all,

Also moving from O&G to mining. I would appreciate any guidance how to perform an integrity audit on HDPE- DR 7 and DR 9 slurry tailing pipeline > 20 inch.

Many thanks,


RE: Calculation of Load on Centre Idler Roll

Much better to delete this and start a new post in the piping and pipeline forum.

Don't mix new items in an old post.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

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