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pulley size

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capt.ron

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#1
i have a hydraulic motor that turn 914 rpms with a 4 1nch pulley i want to change to a motor that turns 760 rpms what size pulley will i need to get the same rpms
 

CluelessNewB

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#2
i have a hydraulic motor that turn 914 rpms with a 4 1nch pulley i want to change to a motor that turns 760 rpms what size pulley will i need to get the same rpms

( 4 x 914) / 760 = 4.81

So you probably need to decide between 4-3/4 or 5"
 

eded59

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#3
4.8 inches

4.0 x pi x 914 = 11485 inches per minute

4.75 x pi x 760 = 11341 IPM

5.0 x pi x 760 = 11938 IPM
 
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JimDawson

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#4
914 / 760=1.202

4 x 1.202 = 4.810, new pulley diameter

This is an approximation and assuming the current ratio is 1:1, based on the information provided.

It would be more accurate if you gave the current motor rpm, and both pulley sizes.
 

CluelessNewB

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#5
This is an approximation and assuming the current ratio is 1:1, based on the information provided.

It would be more accurate if you gave the current motor rpm, and both pulley sizes.
I'm confused!

He did give the current motor RPM = 914 and you used it for your calculation!

Assuming he keeps the same driven pulley size why would the driven pulley size make any difference?
 

JimDawson

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#6
I'm confused!

He did give the current motor RPM = 914 and you used it for your calculation!

Assuming he keeps the same driven pulley size why would the driven pulley size make any difference?
I stand corrected, I need to work on my reading comprehension. I read hydraulic motor as hydraulic pump, thinking that it was being driven by a motor. :nuts: So please disregard my idiocy.
 

12bolts

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#7
So you probably need to decide between 4-3/4 or 5"
Ron, if its that critical you can possibly turn a 5" pulley down to 4.8, or you could make one....

Cheers Phil
 

capt.ron

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#8
thanks everyone it's not that that important that it be exact just close i am going with 5 inch
 

KBeitz

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#9
Save this photo. You all might need it some day...

Pulley Speeds and Diameters.jpg
 
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