Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Overhung Load Equation

Overhung Load Equation

Overhung Load Equation

I want to extend the output shaft of a gearbox by 6 inches, from the face of output seal to the end of the shaft would be 6.00 inches. I want to calculate the overhung load but all of the equations that I find seem to focus around having a pulley or sheave at the end of the standard output shaft, but we will not be adding a pulley or sheave to the end of the shaft. The equation in the gearbox manufacturers catalog is (HP*126000*Overhung Load Factor)/Pitch Diameter*Output RPM.

Does anyone have an equation I can use?


RE: Overhung Load Equation


the equation you cite covers the reaction forces on the output shaft imparted by a <torque transmitting element> as are e.g. pulleys or sheaves.
This equation still not covers the forces from the weight of these appliances or takeup forces etc.
The factors 126k and OLF are imo impossible to be read / understood w/o the document they originate from, this is specific to the machinery you're looking at (perhaps someone else too..).
Vertical (to shaft axis) loads influence the liefcycle of the shaft and the shaft bearings and are a matter closely watched by the gearbox designers / manuf.-s.
So, some questions arise:
- Tech. background of the shaft prolongation?
- Would a sketch be possible?
- Why not contact the gearbox OEM on this? (They'll be helpful, I'd hope)

Roland Heilmann, Leipzig, FRG

RE: Overhung Load Equation

Hi seventofour

How are you going to extend the shaft by coupling? What is the purpose of the shaft extension and what will it be connected too?

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

RE: Overhung Load Equation


How are you applying a side load to the shaft? Gears cause side loads too!


Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close