Most of the domestic oilfields have entered the period of high water cut. Conventional plunger pumps are one of the major oil recovery methods. Due to the factors such as high sand content, high water content, high salinity, high temperature steam heavy oil recovery, polymer injection and strong corrosive medium environment, the average pump inspection period of piston pump wells is shorter and shorter, and some are not even To 30 days to check the pump, seriously affecting the development of oil fields. According to the plunger pump failure reasons, such as oil well water, sand, corrosion and scaling implant injection, high salinity, bottom hole temperature, the liquid medium corrosion, well structure and the plunger pump itself Structure does not meet the plunger and pump cylinder surface treatment and the surface material can not meet the demand, etc., plunger pump protection methods are varied, mainly in the following categories: Pump structure changes In the sand production wells, conventional plunger pump often appear sand card plunger, sand buried sucker rod, sanding cylinder and plunger and other phenomena, the pump failed prematurely. In response to these problems, pump developers designed a long plunger short pump sand control pump. In the production process, there is always a part of the plunger exposed to the pump cylinder, grit into the pump barrel and the plunger is not easy to enter the gap between the stop card to stop after the sand stuck sand or sand buried plug the accident effectively extended the well Free repair period. Some pumps also add some auxiliary components, such as scraping up and down the cup, the function of joints, the purpose is to further prevent sand deposition between the pump barrel. Self-rotating plunger pump allows the plunger at each stroke of a random rotation, and constantly changing the contact surface of the plunger and the pump cylinder, the plunger circumference gradually wear uniform at the same time the sand or scaling from the plunger and the pump cylinder Between the discharge, to solve the abrasive material aggregation caused by serious positioning wear and pole trip. In order to achieve the sand control effect, a gap free sealed oil pump and a piston oil pump have also been developed. Improve the shape of the groove on the plunger and groove position can play a certain amount of sand sand control effect. According to statistics, the plunger pump failure on the valve cover more prominent, the failure of the main form of fracture. Occurred in two parts: First, the valve cover at the oil hole; First, the connection rod and the upper thread roots. To this end, specially designed and developed on the anti-off on the valve cover to prevent the pump working on the valve cover fracture. Some pumps are also designed to have multiple swimming Versailles and fixed Versailles in order to prevent leaks between Vernier balls and Versailles. "Vacuum" chamber type double plunger pump is used to extract the viscous and viscous oil and water emulsion, it is the use of "vacuum" chamber when the pumping unit under the stroke caused by sucker rod and plunger Of the downward force, so that they produce downward forced movement. Diaphragm pump is used to extract the abrasive particles (such as sand and mechanical impurities) and corrosive media containing crude oil, which is the use of diaphragm pump will be the working elements to be protected against sand, salt and corrosive Fluid formation of the media contact, to extend the service life of the pump. Pump material and surface treatment improvements General lining materials for the 20CrMo carburizing or 38CrMoA nitriding, there are 45 steel electrochromic chrome, carbon steel plunger chrome plating treatment. Such cooperation does not meet the high sand, high salinity media environment, from the failure of the investigation and analysis of the point of view, with the deputy protective layer is easily damaged by abrasion of high hardness quartz sand, followed by serious electrochemical Corrosion, resulting in protective layer off, can cause serious pump accident. Judging from the current actual situation of the oilfield, the plunger using Ni-based spray coating alloy has been relatively common, can partially solve the above problems, but the effect is still not very good for serious sand or serious scaling. With the surface treatment technology and material processing technology improvements, will continue to introduce new plunger and pump cylinder material and surface treatment process, then pay particular attention to the plunger and the barrel of the material to optimize the match. Anton Valve Engineering Co., Ltd. is about to launch the special ceramic pump, will greatly enhance the plunger pump anti-sand, anti-scaling, anti-wear, high temperature performance in several areas. Valve and valve seat material most of 3Cr13, a few for the 6Cr18Mo and 9Cr18Mo. From the field of application of view, its hardness, wear resistance and corrosion resistance is poor caused by fixed valve damage, the main reason for failure. There are oilfield carbide car seat replace the original 6Cr18M, but note that the valve ball will increase the density of the pump resistance and pressure drop at the fixed valve. There are also ceramic Versailles and ceramic seat, ceramic Versaille may sometimes crack, also pay attention to use. Pump related string structure change Through the use of ultra-high strength rod string, and the bottom of the column with a certain weight weighted rod, you can prevent the bending of the pump cylinder to reduce the plunger and pump cylinder wear and tear. Manufacturing process Due to the differences in the processing, material handling and assembly of the pump barrel plungers, various parameters of the pump of the same specification can not be completely identical, thus causing a variety of unexpected accidents. Quality control during the processing is to be strengthened. Other measures Such as the use of low-stroke long-stroke low-stroke parameter matching; select a sufficient liquid supply wells and to maintain the same pump efficiency, the submergence of the pump should be slightly larger than the design of small pumps can also extend the pump to some extent .