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at the beginning of my career, as a Design Engineer, I had the task of sizing the high-strength bolts operating with tensile load. A structure of the Angra Nuclear Power Plant, this in the decade of 80. The company that worked used high-strength screws as splints for joints in Bridges and Overhead Gantry Cranes, and in this situation the screws do not undergo load variations, only the pre-tension load, but that's not what happens when these screws suffer tensile loads. To develop the calculations I studied at home at night, and I summarized the book Elements of Machines by Dobrovolski, that follows below.
IMPORTANT NOTES:
1 - Notice that the traction load P, increases the pre-tension value, i.e, cannot adopt the pre-tension values of DIN or other standard., because depending on the value, the operating screw may break.
2 - If the pulling load is variable, we will have to check the screw for fatigue, since there will be load variation on the screw.
3 - It is important to check the strain x force graph, that the tensile load reduces the pressure in the V' joint, if this pressure reaches zero, this joint will come loose, therefore, this calculation is very important, can't be despised.
Conclusion: After evaluating the bolt sizing of a rigid coupling that operated in flexion (beyond the twist), of a german multinational, I was horrified, engineering had gone far, and I realized the need to pass on this particular technical document of mine, and as this multinational does not fail to see my articles, I know I will be contributing and avoiding possible accidents.