Mechanical Simulation Analysis And Structural Optimization Of Sucker Rod String

As an important fossil energy and chemical raw material,petroleum occupies an important position in the development of national economy.As the premise of utilizing petroleum resources,petroleum exploitation plays an important role in the whole petroleum industry.Under the present technical condition,the exploitation of oil is still dominated by the rod lifting system.As a key component of the oil rod lifting system,the life of the sucker rod string is an important factor affecting the length of maintenance free period.The service life of the sucker rod string is closely related to its stress status.The study on the stress status of the sucker rod string is the premise of extending the service life of the sucker rod string and extending the repair free period of the oil well,so it has extremely important practical significance.In view of this,the research contents of this paper mainly include the following aspects:(1)this paper analyzes the failure modes of sucker rod string in combination with relevant literatures at home and abroad,and finds that the sucker rod is mainly subjected to cyclic load and frictional load,and concludes that the main failure modes of sucker rod string are fatigue fracture and partial wear failure.(2)based on the study of domestic and foreign information about sucker rod string stress under the premise of the rod string downhole stress model is established,the model takes into account the rod string gravity,buoyancy,inertia force,solid friction,fluid friction and fluid forces on the influence of the rod string stress,and using this model,the analysis of the pumping unit stroke,stroke of the rod string stress influence;The influence of well Angle and hole curvature on the force of the rod is analyzed.The influence of rod diameter on rod life is analyzed.The effect of the diameter and the position of the anti-wear block on the anti-deflection wear of the bar string is analyzed.(3)the optimization method of rod string for rod string life and the anti-friction block arrangement method for reducing rod string eccentric wear were proposed.It mainly includes the optimization of pumping parameters,rod diameter optimization,centralizer size and position optimization.(4)in this paper,the sucker rod string mechanical model programmed work behavior,and with MATLAB GUI platform,encapsulation is compiled the rodpumped well tube rod system dynamics simulation software,the software can realize the sucker rod string downhole stress analysis and calculation,the rod string contact behavior analysis and prevention guidance of eccentric wear,combination analysis of sucker rod string,fluid properties,pump and swabbing parameters on the influence of the rod string stress,extend the service life of rod string based on the rod string of combinatorial optimization and so on.