Quote:
Originally Posted by Bob from Northport
I don't know where the 225 torque came from. Way too high. 100 lbs and then adjust for the cotter pin
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I would be afraid of stretching the hub where it jambs onto the shaft taper - not to mention the difficulty in getting it off afterwards.
I've often felt that the shaft nut/thread are somewhere between SAE Grade 5 and Grade 8 bolting.
https://www.boltdepot.com/fastener-i...ed-Torque.aspx
Quote:
9/6 Fine: Grade 5 = 91ftlbs - Grade 8 = 129ftlbs
5/8 Fine: Grade 5 = 128ftlbs - Grade 8 = 180ftlbs
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https://www.bayoucitybolt.com/torque-to-bolts.html
Quote:
Clamp load is typically around 75% of a bolt’s proof load; that is, the highest stress the bolt can accommodate before experiencing plastic deformation. The proof load itself is usually 85% to 95% of a bolt’s yield strength, but the clamp load is significant because it is what ultimately provides the clamping pressure. Once the clamp load is determined, finding the correct torque value for a bolt is one simple calculation away.
T = K x D x P
Where:
K: coefficient of friction (as determined by bolt surface treatments)
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Table there but K for a lubricated situation (recommended) is usually 0.18
And from this the torque table above is calculated.
"Clamp Load" has it's own transference (K) from movement along the taper to actual expansion (stretch) of the hub which like torque is a function of the friction between the two parts.
220ftlbs certainly above the elastic limit for the shaft thread. Your success to this point may be due to your particular torque "K," which is at best "variable."
Joe K