Analysis And Improvement Of Seals For Rotary Liner Hanger Bearing

The Bearing system is an important part of the rotating liner hanger in Ultra-Deep Well Drilling.The Sealing element,as an important components for the rotating liner hanger,it's failure problem directly reduces the safety and stability of the bearing and then affects the well cementing efficiency.In this paper,two kinds of Y type seal ring and O type seal ring,which are needed for the rotating liner hanger bearing are researched and analyzed by finite element analysis software ANSYS,and the structure of Y type seal is improved.Firstly,the seal principles,design requirements,structures and characteristics of the two kinds of seals are introduced briefly.The two-dimensional axisymmetric finite element models are built by the method of ANSYS parametric modeling.Material parameters,structure types,contact types and settings,boundary conditions and loading modes are also established.Secondly,analysis of the influence of the compression ratio,working pressure,seal clearance and other factors on the maximum contact stress and maximum equivalent stress of O-ring are made by ANSYS software.Then,with the help of ANSYS software,the influence of working pressure on the maximum contact stress and maximum equivalent stress of Y-ring is analyzed.The reliability of Y-ring in response to maximum contact stress and maximum equivalent stress was calculated by using PDS probability design module.Through the sensitivity analysis,the design parameters b1 and cc which have higher significance sensitivity to the maximum contact stress and the maximum equivalent stress are obtained for the next step to lay the foundation for optimization.Finally,selecting the zero-order optimization method,the maximum contact stress of Y-ring is extacted as a state variable through programming,and the maximum equivalent stress is also extacted as a objective function.By comparing the results before,it is found that the optimized results of the maximum equivalent stress is obviously reduced by about 30%,and the maximum contact stress can be reduced by about 10% under the condition that the sealing performance can be ensured.This verifies the rationality of the optimization method and the optimization results.Methods Based on the combining of probability statistics and ANSYS analysis technology,can well analyze the uncertain factors on the influence of the sealing performance and effectively save the cost,which has a certain guiding significance in engineering application.