How many times can you torque a bolt?
Plain ASTM A325 bolts, however, possess sufficient ductility to undergo more than one pretensioned installation as suggested in the Guide (Kulak et al., 1987). As a simple rule of thumb, a plain ASTM A325 bolt is suitable for reuse if the nut can be run up the threads by hand.”
How do you calculate residual torque?
Mark the tightened fastener and surrounding application. In the tightening direction, begin to slowly apply force to the tool until the first movement in the fastener is noted. The reading recorded is a good indication of the original torque applied to the joint. This is the best way to determine residual torque.
How do you calculate torquing?
Torque Calculation A practical way to calculate the magnitude of the torque is to first determine the lever arm and then multiply it times the applied force. The lever arm is the perpendicular distance from the axis of rotation to the line of action of the force. and the magnitude of the torque is τ = N m.
Is code for bolt tightening torque?
10 Snug Tight – The level of tightness attained by a few impacts of an impact wrench or by the full efforts of a man using a Standard/ podger spanner or a spud wrench. Bolts, nuts and washers shall conform to IS 3757 : 1985, IS 6623 : 1985 and IS 6649 : 1985 respectively.
How do you measure torque loss?
To conduct this test, take a screw or bolt that is tightened down and begin to loosen it. When the fastener breaks loose, record the torque reading. The torque value to loosen the fastener is the approximate torque that was applied to the joint.
What is the formula for net torque?
The net torque is therefore τnet=∑i|τi|=160−60+120+10=230N⋅m.
What is the formula for calculating frictional torque?
τ fric = b 0 sgn ( ω ) + b 1 ω , where b0 is the Coulomb friction torque (sgn(ω) just returns the sign of ω) and b1 is a viscous friction coefficient.