The wear of oil well pipes in oilfield pumping units is severe; what methods can be used to avoid this?
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The following describes a situation in an oil field where, after just over a year of use, the pump piston began to abrade against the inner wall of the tubing, resulting in the premature failure of the tubing. There are two reasons for eccentric wear: one is the use of oil containing high levels of corrosive substances such as hydrogen sulfide, and the other is friction against the well wall during the movement of the pump plunger. We usually call it abrasion. Take a look to see if there are any good protection methods to avoid uneven wear.
The following methods can be employed to avoid uneven wear of oil well pipes: 1. Use well pipes made of corrosion-resistant materials, such as stainless steel or special coated anti-corrosion materials. 2. Optimize the design of the pump to ensure smoother piston movement and reduce direct friction with the wellbore walls. 3. Regularly clean and filter the oil underground to remove corrosive substances such as hydrogen sulfide. 4. Use lubricants or add anti-wear additives to reduce friction between the piston and the inner wall of the well pipe. 5. Regularly inspect and maintain the pump units and their components to ensure that all parts are functioning properly and to reduce abnormal wear. .
1. Material of the rod-tube structure and anti-wear coating: Oil pipes with HDPE (high-density polyethylene) plastic linings improve their resistance to wear by modifying their structure. Its structure consists of an HDPE pipe embedded within a regular oil pipe. Compared to metal pipes, HDPE pipes have advantages such as light weight, corrosion resistance, wear resistance, rust prevention, a low thermal conductivity, and a low friction coefficient. However, the installation of an inner liner tube results in a reduction of the inner diameter, and appropriate measures must be taken to ensure the proper operation of downhole tools ； HDPE has limited temperature resistance, and there are requirements regarding the depth of insertion ； It is expensive, costing about 1.7 times that of ordinary oil pipes. Therefore, its use has certain limitations. 2. Rod rotation: During the production of oil wells, various rotating devices are used to rotate the rods, thereby increasing the degree of wear on them from a few degrees or a dozen degrees to 360°. This helps to ensure even wear on the rods, reduces localized wear, and extends their service life. 3. Hollow sucker rod technology: In this approach, hollow rods are used in place of tubing and solid sucker rods; the pump cylinder is suspended directly on the casing, with the hollow rods driving the plunger to carry out the pumping process. This technology features high pumping efficiency, which helps reduce costs and labor intensity. It can directly address the problem of uneven wear on the pipes and rods that is inevitable with pipe strings composed of solid rods and tubing. Furthermore, while maintaining the fluid production rate constant, production parameters should be adjusted appropriately by changing from short strokes with high frequencies to long strokes with low frequencies, thereby increasing the area subject to uneven wear and reducing the frequency of such wear, in order to extend the service life of the oil pipes and pumping rods