Design And Research Of Hydraulic Telescopic Downhole Tractor

At present,horizontal wells and large-displacement wells have become major wells for oil and gas development,and more and more maintenance,inspection,and maintenance work have been done in horizontal wells and large-reach wells,and higher requirements have been placed on the performance of downhole tools,especially downhole tractors.In response to these needs,this paper has designed a hydraulic telescopic downhole tractor with large traction and high power,based on the research of tractors at home and abroad.In view of the above requirements,based on the research of domestic and foreign tractors,this paper designed a hydraulic telescopic downhole tractor with large traction and high power,which has completed the working mechanism study of the hydraulic telescopic tractor,and the tractor structure Design,mechanical analysis,optimization design,prototype and experimental research.This paper focuses on the above research content and mainly carries out the following work:(1)Research and analysis of the research status of tractors at home and abroad.By investigating the products,literature,and field applications of tractors at home and abroad,the research status at home and abroad is analyzed and the research ideas and research contents of this paper are proposed.(2)Hydraulic telescopic downhole tractor design.Through the working mechanism study of the hydraulic telescopic downhole tractor,the working mechanism of the tractor designed in this paper was determined;based on the best working mechanism,the hydraulic control system design,support mechanism design,telescopic mechanism design,power system design and seal mechanism design were carried out.Therefore,the overall design of the double-sloped block tractor and the spring-plate type retractor can be determined.(3)Mechanical analysis of hydraulic telescopic downhole tractor.According to the mechanism design of the two retractors,a locking mechanical model under the action of the load force is established,and the traction lock conditions of the retractor are analyzed;the dynamic models of the two retractors are established by ADAMS software,and two kinds of retractors are The locking performance of the device was analyzed,the traction lock condition was verified,and the optimal structure of the hydraulic telescopic downhole tractor was determined to ensure the reliability of the two tractors under the action of large traction forces.(4)Performance analysis of hydraulic telescopic downhole traction device sealing mechanism.The C-slip ring seal was used in the retractor movement mechanism,and the 2D axisymmetric model was established using abaqus software.The key factors for the good sealing of the C-shaped slip ring were analyzed and the best installation clearance of the C-slip ring combined seal was obtained.The effects of friction coefficient,working pressure,seal gap and reciprocating speed on the sealing performance.(5)Analysis of the fatigue life of spring tabs of hydraulic telescopic downhole tractors.The fatigue life of the spring plate has a direct influence on the service life of the spring plate type retractor.The fatigue simulation model is established using abaqus and fe-safe software,and the fatigue life of the spring plate under the design parameters is analyzed.The spring plate is estimated under the design parameters.The number of wells operating in horizontal wells;at the same time,the influence of roughness,residual stress,spring span,and spring thickness on the fatigue life of the springs was studied,and the optimal parameters of the springs were optimized.(6)Experimental research on hydraulic telescopic downhole tractor.The output pressure of the control section of the retractor was tested,and the machinability of the moving mechanism was described.Through experimental device design and prototype machining,the double-diagonal retractor and spring obtained by theoretical analysis were verified by experimental methods.The traction lock condition of the chip tractor ensures the movement performance of the two hydraulic telescopic downhole tractors.In summary,this paper has designed a large traction force,high power hydraulic telescopic type by studying the working mechanism of hydraulic telescopic downhole tractors,structural design and optimization analysis,mechanical analysis,sealing mechanism analysis and performance experiments.Downhole tractors have a traction force of 10,000N and a traction speed of 400m/h,which is of great significance for the engineering of domestic large traction telescopic tractors.