Behavior Analysis of a Wire Rope Replacing Sucker Rods with Finite Element Simulation

Abstract

In this paper, a state-of-the-art wire rope is chosen for investigation regarding its applicability as a sucker rod string. Finite element simulation with Abaqus has been used for a detailed analysis of the rope's performance and possible failures along with its length. The sucker rod string is a key component of sucker rod pumps, transferring the reciprocating movement of the surface polished rod to the downhole pump plunger. It is, however, exposed to severe cyclic loads, causing several complications from damaged rods and broken couplings to time-consuming workover procedures. Hence, continuous strings like wire ropes can be a convenient replacement for the conventional design. The mechanical properties of the introduced wire rope demonstrate high tensile strength and great resistance against creep and fatigue while its uniform design eliminates the chances of connection failure. The proposed wire rope was designed to work in tandem with a sucker rod anti-buckling pump (SRABS) to facilitate its motion. The performance of this system was then simulated using a combination of MATLAB and Python codes, visualized in the interface of Abaqus. These simulations confirm that this wire rope can indeed replace the rod string in a sucker rod pumping unit. Detailed stress, load, and movement profiles were also compiled to allow for a comprehensive analysis. The results pointed out that pumping with a wire rope can be just as productive, or surpass the productivity of a system using conventional sucker rods. They indicate that the efficiency of this design highly depends on the geometry and depth of the well, type, and size of the pump, the compressibility of the produced fluid and string material elasticity. The optimization of the wire rope's performance could be achieved by using compatible Pumpjacks and proper downhole equipment, such as string protectors, all operating together under an optimum pumping speed. This paper presents a noteworthy comparison between the performance of a conventional rod string and a wire rope at two reference wells. Laboratory and field tests are being planned to investigate the full capacity of the rope.