Shop Floor Talk  

Go Back   Shop Floor Talk > Welding and Metalworking Forums > Fabrication

SFT Search:
Thread Tools Display Modes
Old 12-05-2013, 04:34 PM
JustinLiang JustinLiang is offline
Join Date: Jun 2013
Location: Vancouver
Posts: 2
Default Oversized Pulley Bore Hole

What would happen if the bore hole of a pulley in a conveyor was significantly larger than the shaft like in the figure below:

I would imagine if the RPM was high, the whole system would shake violently. However, what if the RPM was around 30 RPM. Would the conveyor still function properly? At such low speeds I feel like it would still work, however, I have never seen something like this in the industrial world which is why I am curious.
Attached Thumbnails
Click image for larger version

Name:	IcUWJMe.png
Views:	745
Size:	6.7 KB
ID:	111680  

Last edited by cutter; 12-05-2013 at 04:53 PM. Reason: remove embedded image; upload attachment
Reply With Quote
Old 12-05-2013, 04:50 PM
Walker's Avatar
Walker Walker is offline
Standard of Excellence
Join Date: Aug 2004
Location: Cave Creek AZ
Posts: 4,671

If it is an idler it will flop around until self destruction. If it is a driver then the shaft spin and wear itself a groove through the side.
Chief slag chipper and floor sweeper, Ironwood Artistic
Reply With Quote
Old 12-05-2013, 04:55 PM
cutter's Avatar
cutter cutter is offline

12-29-1943 to 1-17-2020
Curmudgeon emeritus
Join Date: Jun 2004
Location: Lubbock,Texas
Posts: 33,097

Justin, please read our FAQ. We do not post embedded images for reasons explained there.
Housekeeping Staff: the Gatekeeper
Director of Policy, Syntax and Grammar (by appointment)

"Dr. Chandran, will I dream?"

Just Keep Walking

"I am not a body, I am free.
For I am still as God created me."
Reply With Quote
Old 12-05-2013, 05:20 PM
milomilo's Avatar
milomilo milomilo is offline

4-13-1949 to 5-21-2023
Auction Addict
Join Date: May 2010
Location: Wheatland, Wyoming
Posts: 18,859

What are the dimensions of the shaft and the bore?

One of the penalties for refusing to participate in politics is that you end up being governed by your inferiors. Plato


B biggest
I idot
D democrats
E ever
N nominated
Reply With Quote
Old 12-05-2013, 06:13 PM
JustinLiang JustinLiang is offline
Join Date: Jun 2013
Location: Vancouver
Posts: 2

Originally Posted by milomilo View Post
What are the dimensions of the shaft and the bore?
The shaft diameter is approximately 1 inch and the bore is approximately 2 inches.
Reply With Quote
Old 12-05-2013, 08:25 PM
Ricker Ricker is offline
Junior Member
Join Date: Jan 2008
Location: Jamestow NY
Posts: 22

I made a tension pulley for one once similar to the drawing.
I used 1" pipe ang 1/2" round bar stock. Ran for a couple years
in a factory setting not sure if its still there or not. FYI the conveyor
wasn't in constant motion and thr "pulley was at about 40-60 rpm.

Reply With Quote
Old 12-05-2013, 08:28 PM
camdigger's Avatar
camdigger camdigger is offline
Roving Reporter
Join Date: Aug 2008
Location: Central Oilberta
Posts: 4,349

At low speeds, the behaviour may just be to roll on the shaft IF the tension is just right.

Even so, with such large clearance, the behaviour of the pulley wheel will be unpredictable. Hopping, flopping side to side, etc may happen depending on the dynamic load fluctuations.

Better to just put in a 1x2 bushing imho....
Design to 0.001", measure to 1/32", cut with an axe, grind to fit..
Reply With Quote
Old 12-06-2013, 02:28 PM
kbs2244 kbs2244 is offline
Elite Member
Join Date: Sep 2006
Location: Way North Illinois
Posts: 1,675

If both shafts are rigidly mounted, and you have good traction on the mateing surface, what you have is a gear reduction.
This was a somewhat common way for the old slow water wheels to speed up the shafts in the mill.
They would have gear teeth on the inside of the outside rim that would mesh with a gear on a shaft going through the mill wall.
20 to 1 ratios were common (20 foot wheel and 1 foot shaft gear)
This was an alternative to having the wheel axel come trough the wall and doing the speed up inside.
Reply With Quote

bore, hole, oversized, pulley

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Web Search:

All times are GMT -5. The time now is 11:29 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.