Pipe String Mechanical Analysis Software And Database For Well Remedial Service

The distribution of oil and gas fields in our country is fragmented,so high-angle wells and horizontal wells are ofen apply to oil and gas exploration.During the overhauling operation,the workover string has complex forces in the space helical well trajectory,and it is difficult for the WOB to pass to the bottom of the well,in addition,operators which lacking of scientific guidance basically overwhelmed their work experience,resulting in frequent accidents in well workover.An pipe string mechanical analysis softare are developed in order to solve the problem that operater lack scientific guidance and the workover data are scattered due to a lot of typical workover cases with reference value have not been recorded in time.This software consists of pipe string mechanical analysis module and database module.The pipe string mechanical analysis module can carry out the finite element analysis under the typical working conditions,and provide the theoretical basis for the workover technicians to formulate the workover plan.Database module compiled successful workover cases information to facilitate the novice staff to learn and refer.In order to complete the pipe string mechanical analysis software and database development,this paper has done the following research work:(1)Four key problems of pipe string mechanics have been studied as below.The geometric model of the pipe string was established according to the spline interpolation algorithm.During this process a more efficient algorithm is proposed to deal with azimuth mutation;The pipe load under different conditions is analyzed;A stochastic friction and contact model was proposed for the contact problem between the pipe string and the casing,boundary conditions are analyzed;The damping effect of mud was studied,and the flow table of the pipe element was designed.(2)The finite element method is used to establish the transient dynamic equation of the pipe string,analyzing the effects of velocity,friction and buckling load on performance of pipe string.The simulation analysis of the pipe string acording to the data of 12-5-1 in BigHarbor to study the transmission of the axial force of the pipe string and friction distribution along the depth of the well.(3)Workover database was established,which is divided into three sub-modules,namely basic data management module,standard library module and construction parameter management module.The basic data management module of the well is mainly used to record basic information such as the inclination data of the well bore trajectory,the information of the oil plant where the well is located and the information of the well structure;The workover parameter management module is used to store and manage the successful workover cases;standard library module is used to store tools and workover tools commonly used tools such as standard and material information.