# Thread: Force acting on HTD pulleys?

1. ## Force acting on HTD pulleys?

Does anyone know how to calculate the force in Newtons which pulls the pulleys together as an HTD belt is accelerated as I need this figure to allow me to work out how safe my current setup is?

An esimation is 500N, but I would like to have a more accurate figure to work with Dunc  Reply With Quote

2. ## Re: Force acting on HTD pulleys?

If you know the torque of your engine you can use

Torque (Nm) = Force(N) x Distance (radius of your pulley in metres)

so Torque/Distance = Force

35Nm with a 50mm diameter pulley gives me about 1400N

hope that helps

Tony  Reply With Quote

3. ## Re: Force acting on HTD pulleys?

Here are some numbers my computer could come up with:

[img]index.php?t=getfile&id=177&private=0[/img][img]index.php?t=getfile&id=178&private=0[/img]

[img]index.php?t=getfile&id=182&private=0[/img]

Bearings - Basic dynamic load rating

Technical Section

Understanding Bearings for the Fan Industry  Reply With Quote

4. ## Re: Force acting on HTD pulleys? Originally Posted by tonybroad
If you know the torque of your engine you can use

Torque (Nm) = Force(N) x Distance (radius of your pulley in metres)

so Torque/Distance = Force

And if you don't know the torque but do know the power being transmitted, then

Force(N) = Power(Watts) / Velocity(m/s)

where

Velocity(m/s) = Revs(rpm) x 60 x 2 x pi x radius(m)

Note that the Force derived by either method is strictly the differential tension between the two sides of the belt. If the return side is close to slack then the Force is the RADIAL load on the bearings.

The AXIAL load on the fan bearing is the thrust; on the other end the axial load will be low.

Nick  Reply With Quote

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•