Tightening torque deformation under the action of the compatibility equation connecting thread

According to the design of the actual working conditions underground wells tied back and re-entry device , designed for re-entry device tieback and the structural model to determine the major mechanical problems to be solved . Re-entry device, the load transfer between the sleeve threaded connections rely on to achieve this end , the establishment of a preload force of the re-entry device connecting thread mechanical model is derived under the pretension deformation compatibility equation  High pressure ball valve  , the use of a dedicated software program prepared by its approximate solution is obtained , so as to carry out the thread , threaded joints and the contact face of stress analysis and strength check laid the foundation for this new type of connection thread structure design and  2 way manifolds  provide a theoretical basis . In addition, the proposed device oval tieback casing forming a nonlinear finite element model and the double casing downhole branch  5 way manifolds  element analysis model . Oval tube plastic deformation in order to obtain the nonlinear characteristics of the finite element analysis software uses two different methods to study the round casing in a non- uniform deformation under load and stress state , and to determine the steel casing material springback deformation after the plastic deformation is very small .