When the relative strength ratio of nut-to-bolt thread is high, the weaker of the two threads will deflect under the relatively stiff action of the other. The rules of the ASME B1.1-1989 provide general design rules for designing non-critical threaded joints. Most threaded joint designs are based on these rules. In most cases, the strengths of the stud and the nut are about the same. This paper addresses plastic deformation and strain in the threaded part of a component (stud) whose strength is about 7 times more than the mating threads. An axisymmetric finite element analysis was performed using nonlinear material properties and nonlinear contact elements between the surfaces of the threads. The results were used to calculate the collapse load for the thread following the rules of Appendix F of the ASME B&PV. It was found that the collapse (maximum allowed) load calculated using this nonlinear finite element approach and Appendix F of ASME code is 50% higher than the load calculated using the conventional elastic methods given in the ASME code rules would be acceptable.

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