Which is the correct formula for torque and tension?
Accepted formulae relating torque and tension, based on many tests are: M = P x D M = torque lbf.ft 60 P = bolt tension lbf D = bolt dia.ins . Or for metric sizes: M = P x D M = torque N.m 5000 P = bolt tension Newtons D = bolt dia. mm These formulae may be used for bolts outside the range of the tables overleaf.
How does torque affect the tension of a fastener?
Tension is the force that actually holds an assembly together. Put another way: A bolt can stretch similar to a spring, as it becomes tightened once all the parts of the assembly are brought together. The higher the torque applied to the fastener, the more tension is created as the bolt stretches.
How does a direct tension washer measure torque?
Specific Tension can be accurately reflected in the number of rotations a fastener needs to bring the parts of an assembly together. Direct Tension Indicator. A Direct Tension Indicator washer (DTI washer) has protrusions that compress when the joint is tightened.
How to determine the torque of a bolt?
The wrong way, asserts Archer, is to pick a number off a standard engineering table or to rely solely on the classic equation, T = KDP, in which T is the target tightening torque; K is the coefficient of friction, or nut factor; D is the nominal diameter of the bolt; and P is the desired tensile load on the bolt.
How is the torque angle to tension test?
The torque-angle to tension test is performed in the same way as the torque-angle to failure test. Sample joints are tightened to the yield or failure point of the fastener. In this case, however, engineers are looking for torque that produces a specific clamp load.
Tension is the force that actually holds an assembly together. Put another way: A bolt can stretch similar to a spring, as it becomes tightened once all the parts of the assembly are brought together. The higher the torque applied to the fastener, the more tension is created as the bolt stretches.
What’s the torque tension for a Grade 9 nut?
Use Prevailing Torque All-Metal Nut chart if using this style of nut. D = Nominal Diameter F = Clamp Load For J429 Grade 5 and 8, FNL Grade 9, A574, Class 4.6, 8.8, 10.9 and 12.9, the clamp loads are listed at 75% of the proof loads specified by the standard. For A307 Grade A, 75% of 36,000 PSI is utilized. A193 B7 uses 75% of the yield strength.
Specific Tension can be accurately reflected in the number of rotations a fastener needs to bring the parts of an assembly together. Direct Tension Indicator. A Direct Tension Indicator washer (DTI washer) has protrusions that compress when the joint is tightened.