Study On The Influencing Factors Of Eccentric Wear Of Pipe Rod And The Application Of Liner Tubing In Coalbed Methane

Due to the lack of lubricity and corrosiveness of coal-bed water,the eccentric wear of pipe and rod in coalbed methane is particularly serious.At present,most of the CBM wells use the method of installing inner liner to control the eccentric wear of the pipe rod.However,due to the aging of field equipment and the speed of installing inner liner is too slow to meet the needs of CBM wells.In this paper,the influencing factors of eccentric wear of pipe rod in coalbed methane are analyzed,and the inner liner of UHMW-PE is studied theoretically and optimized equipment,and the field application of the inner liner is studied.So as to improve the field production efficiency and effectively solve the problem of eccentric wear of pipe rod in coalbed methane.The specific research contents are as follows:According to the problem of eccentric wear of pipe and rod in coalbed methane,the theoretical analysis of the influencing factors of eccentric wear such as natural well deviation,unstable bending,vibration of pipe rod,and coalbed methane production liquid are carried out,and the distribution law of eccentric wear location is summarized from well trajectory and neutralization point.On this basis,the mechanical model of tubing and sucker rod is established.Based on the technical principle of UHMW-PE inner liner tubing,the performance of UHMW-PE inner liner was studied by wear test and drug resistance test.Combined with the low efficiency of coalbed methane field and the serious aging of production equipment,the structure of the test press and flanging machine is optimized.Through fluent and mechanical software to verify the reliability of common tubing and optimized production of liner tubing,determine the application matching mode of liner tubing,and analyze the field application of liner tubing.The research results show that the factors that affect the eccentric wear of the tube and rod in coalbed methane well are complex and diverse,and the corrosion will aggravate the eccentric wear to a certain extent.UHMW-PE lined tubing with ultra-high wear resistance and good resistance can effectively alleviate the eccentric wear of the tube and rod,and the optimized equipment can greatly improve the lining efficiency on the premise of ensuring the safety of production.The research results have certain guiding significance for the matching technology of using inner liner tubing in coalbed methane and improving the efficiency of field operation.