Direct tension indicators are sometimes used instead of

Problem 3-16

Direct tension indicators are sometimes used instead of torque wrenches to ensure that a bolt has a prescribed tension when used for connections. If a nut on the bolt is tightened so that the six 3-mm high heads of the indicator are strained 0.1 mm/mm, and leave a contact area on each head of , determine the tension in the bolt shank. The material has the stress strain diagram shown.

                                                               Step by Step Solution

Step 1 of 3

Calculate the stress from the stress- strain diagram when strains is 0.1 mm/mm by use of interpolation for the linear line.

Here,  is stress of the when strain is 0.1 mm/mm,  is stress when strain is 0.3 mm/mm,   is stress when strain is  0.0015  mm/mm,  is strain when strain is 0.1 mm/mm,  is strain is 0.0015 mm/mm, and  is strain when strain is 0.3 mm/mm.

Substitute  for , 600 MPa for , 450 MPa for  , 0.1 mm/mm for ,  0.0015 mm/mm for  and 0.3 mm/mm for  .