Help! with V belt sizing

   / Help! with V belt sizing #1  

ArlyA

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Folks, I'm not a ME and don't play one on YouTube. :eek: I'm putting together a 35hp power drive and need it to be clutched. Since the engine could also use some load shock protection, I thought a few V belts attached right on the engine might work. Lets say 5" sheave on the output shaft but any size could be used, and 5" also on the secondary shaft. Of course an idler would be used and actuated, so as to give it a clutch. This would be operating at 3000rpm or nominal gas engine speeds and in cool temps, like below freezing. Bad or good idea?? And what size V-belt (more than one?) should be used? Thanks!
 

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   / Help! with V belt sizing #2  
It will work but also will wear over time.
Alignment will be critical and you'll also want some sort of guides the keep the belt/s in position.

What U describe is a fairly common procedure.

There also exists centrifugal clutches that accomplish the chore but at 35 hp ??? ($$)

I'd suggest looking at snowmobile clutching systems as they are in your HP range.
 
   / Help! with V belt sizing
  • Thread Starter
#4  
We do not want or need a CTV transmission like sleds have. Thanks

It will work but also will wear over time.
Alignment will be critical and you'll also want some sort of guides the keep the belt/s in position.
What U describe is a fairly common procedure.
There also exists centrifugal clutches that accomplish the chore but at 35 hp ??? ($$)
I'd suggest looking at snowmobile clutching systems as they are in your HP range.
 
   / Help! with V belt sizing #5  
Folks, I'm not a ME and don't play one on YouTube. :eek: I'm putting together a 35hp power drive and need it to be clutched. Since the engine could also use some load shock protection, I thought a few V belts attached right on the engine might work. Lets say 5" sheave on the output shaft but any size could be used, and 5" also on the secondary shaft. Of course an idler would be used and actuated, so as to give it a clutch. This would be operating at 3000rpm or nominal gas engine speeds and in cool temps, like below freezing. Bad or good idea?? And what size V-belt (more than one?) should be used? Thanks!
Clutching under no work load?

Are you starting a high inertia load and what rpm does the load run?

Are you able to start in a throttled down condition then go to working speed?​
 
   / Help! with V belt sizing
  • Thread Starter
#6  
Clutching under no work load?

Are you starting a high inertia load?

Are you able to start in a throttled down condition then go to working speed?​

Yes, the engine could be at idle or low speed, for engagement. And yes, the clutch would be engaged while not doing any work.

Not sure this is a high inertia load or not, maybe mid?
 
   / Help! with V belt sizing
  • Thread Starter
#8  
I'd guess we can get away with one or two C sized standard V belts and keep the tension on the low side for 'emergency clutching" action...

Or are we wiser to stay with just one belt, large enough to not routinely fail? I now see 9" is the minim diameter sheave for this size of belts....
 
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   / Help! with V belt sizing #9  
A pair of 5vx belts on a 5.5" or larger pulley will work fine
 
   / Help! with V belt sizing #10  
Yes, the engine could be at idle or low speed, for engagement. And yes, the clutch would be engaged while not doing any work.

Not sure this is a high inertia load or not, maybe mid?
You dont offer any details of application and use. Is it a secret?
 
 
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