Calculation and modeling of rational tightening torque when assembling drill pipes
A review of modern methods of mathematical model-ing of the stress-strain state of threaded connections showed the impossibility of using analytical methods due to the complex configuration of products and the advantage of the finite element method. Existing methods for modeling screwed connections consider only individual stages of the life cycle of threaded connections and do not take into account their mutual influence. A complex model of the stress-strain state of the ADMS and a method for estimating its fatigue re-sistance, including the stages of manufacturing ele-ments, assembling the joint, and operating, are pre-sented. Based on the theory of surface shaping, the reasons for the errors in the profile of a conical thread are considered and a geometric model of the threaded surface is compiled, taking into account these rea-sons, in the form of a system of parametric equations that describe the coordinates of the points of the threaded surface in 3-dimensional space, depending on the parameters threading settings. For additional verification of the adequacy of the re-sults of modeling the SSS in the ADMS, taking into account the application of the operational load, a fix-ture for the testing machine was developed. The fix-ture is designed to provide the possibility of fixing a flat sample cut from the AAMS. Special load devices allow you to simulate the application of torque to the connection.