Design And Manufacture Of Jet Test Machine For Erosion And Research On Erosion-Resistance Behavior Of Oil Well String

Erosion is a phenomenon of metal surface damage caused by relative motion, on microscopic including wear and corrosion and its mutual effect to each other. In the process of oil exploitation and conveying, subsurface tool, tubing and ground tube remit etc. These equipments inevitably bear multiphase flow, especially the high erosion rate of the solid and liquid two-phase flow, leading to the wall of the equipment thinning, carrying capacity reducing, which leads potential safety hazard. Wear is a phenomenon of material surface spoilage or residual deformation when the objects touched each other in relative motion. In the process of drilling and well repairing, casing wear makes its bearing capacity reduced, which have a significant impact to the follow-up well drilling and completion, oil extraction, and the ng.Based on the integration of the advantages and disadvantages of the existing types of erosion test devices, the working conditions on site of oil well tubing string in serving and testing purposes, the paper designed and made a jet erosion test equipment, this equipment includes a injection pump, nozzle, injection room and electrochemical test system, may realize the erosion rate, erosion angle and jet distance controlled, and can compare different materials’ resistance to the erosion.Making erosion tests in erosion test equipment with the casing pipe steel of P110N80and VM140samples to study the influence of the erosion rate and erosion angle and fluid medium and compare these three kinds of material’s resistance to erosion. In the test we find that, erosion rate increased with the increase of fluid rate almost in a linear relationship, and the increasing extent gets greater and greater; The erosion rate of material increase with the increase of erosion angle, when erosion angle is90°, erosion rate achieve the maximum. The P110sample under erosion effect of solid-liquid mixture containing higher sediment concentration lost more weight than that under erosion effect of solid-liquid mixture containing lower sediment concentration. The P110sample under the erosion effect of solid-liquid mixture containing NaC1lost more weight than that under erosion effect of solid-liquid mixture which didn’t contain NaCl. In the same test conditions, the erosion rate of P110sample is the largest, while VM140sample is the minimum,N80is between the two described above.Choosing S135drill pipe/P110、S135drill pipe/N80and S135drill pipe/VM140casing samples tested in MRH-1A drill pipe-casing friction and wear testing machine, checking the impact of casing wear to the contact pressure and speed. In the test we find that, along with the increase of the pressure, wearing capacity increased as well as wear efficiency, and the increase rate gradually larger; When the speed is low, changes of wearing capacity and wear efficiency of P110sample is smaller, while the speed exceed more than170r/min, change range increased. Under the same conditions of pressure and speed, the wearing capacity of N80sample is the most, and that of VM140sample is the least, the wearing capacity of P110sample is between those of N80and VM140samples.