Research Of Tube-rod Corrosion And Eccentric Wear Laws Of Beam Pump Wells In High Watercut Stage

After the development of more than40years, Shengli Oilfield is already at middle orpast development period, and the tube-rod work environment is becoming worse with the riseof water-cut and production rate. The problem is also getting worse for there are moresidetracked wells and deviated wells. Aiming at those problems, the esearch of tube-rodcorrosion and eccentric wear laws of beam pump wells in high watercut stage was done withmethods of field study, theoretical analysis and laboratory test. Through innovations intechnologies of centralizer antiwear, anticorrosion antiwear, instability resisting pump andimprovement of the matched technology of tube-rod corrosion and eccentric wear of beampump wells, the matched technology series of tube-rod corrosion and eccentric wear of beampump wells was formed which would solve different kinds of tube-rod corrosion andeccentric wear problems. The research of tube-rod motion state mechanical analysis and thematched technology series of tube-rod corrosion and eccentric wear was finished after thesimulation of the downhole rod three-dimensional motion and the calculation of the downholeeccentric wear location and the value of its frictional force with the method of finite element.The achievement could be used in the application and optimization of eccentric-wear-prooftechnology which would ensure the maximization of the effect of eccentric-wear-prooftechnology. The outcomes of matched antiwear-tube tests, elastic antiwear pair spring forcetests, antiwear rod coupling performance test and anticorrosion chromium alloy rod testsshow that all centralizing, anticorrosion and antiwear instruments designed meet designrequirements. The large-scale application and dissemination of2132wells in oilfields showthat the matched technology series of tube-rod corrosion and eccentric wear of beam pumpwells could solve tube-rod corrosion and eccentric wear problems. The average productioncycle of these wells is prolonged by a factor of2.5and operating well times decrease by2501,and there are still1517well which still keep up production with the direct economic benefitof198,380,000yuan. Research achievements have very good reference and application valuein solving tube-rod corrosion and eccentric wear problems and elongating workover-freeperiod of eccentric wear wells.