Rotary Cutter Shear Bolt and Slip Clutch

   / Shear Bolt and Slip Clutch #31  
I guess I am doubly protected.
Dangerous assumption. I see indications on the head of that bolt (pg1) that it's a Grade 5. Some manufacturers specify a Grade 2 shear bolt, some a Grade 5. At this point you don't know which. Over-confidence in such "double protection" has all too often led to neglected maintenance on the slip clutch. At that point, you're back to shear bolt only protection - which makes it doubly important that you determine whether it should be by Gr2 or by Gr5.

My recommendation is to service the slip clutch now, and put it on your scheduled maintenance list. Then install an appropriately sized Grade 8 bolt as a simple retainer, and forget all about being "doubly protected".

//greg//
 
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   / Shear Bolt and Slip Clutch #32  
Dangerous assumption. I see indications on the head of that bolt (pg1) that it's a Grade 5 bolt. Some manufacturers specify a Grade 2 shear bolt, some a Grade 5. At this point you don't know which. Over-confidence in such "double protection" has occasionally led to neglected maintenance on the slip clutch. At that point, you're back to shear-bolt-only protection which makes it doubly important that you determine whether it should be Gr2 or Gr5.

My recommendation would be to service the slip clutch now, and put it on your scheduled maintenance list. Then put in a new Grade 8 bolt as a simple retainer, and forget all about being "doubly protected".

//greg//

Excellent advise.
 
 
 
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