Pumping pump efficiency and gas lock condition wells of gas-containing wells are more ideal for the structure of the oil pump and the way to prevent gas heli=1H33.Allrightsreserved. Wells in the middle and later stages of the oilfield are wells or low fluid levels, especially high gas liquids. Compared to oil wells, gas is one of the main factors affecting the pump efficiency of the pump. In the pumping process of the oil pump, there are free gas, dissolved gas and condensate gas in the pump chamber (the portion between the downstream valve and the fixed valve in the pump cylinder). When the pump is stroked, if the pressure in the pump chamber is lower than the saturation pressure of the gas dissolved in the liquid, the gas dissolved in the liquid will be separated from the liquid. When the temperature in the pump chamber is lower than the critical temperature of certain components in the crude oil, the reduction of the pressure also causes the liquid components to partially convert into a gaseous state and become condensate gas. These gases occupy part of the volume of the pump chamber, which reduces the pump's fullness and reduces pump efficiency. When the pump is in the down stroke, the gas-liquid two-phase fluid in the pump chamber is compressed until the pressure in the pump chamber is greater than the pressure in the upper portion of the traveling valve. The traveling valve is opened and the crude oil in the pump chamber is discharged. The sucker valve ball in the gas-containing oil well will normally open hysteresis. When the volume occupied by the gas in the pump chamber is large enough, not only the movable valve will not open during the down stroke, but even the fixed valve may play on the up stroke. Not open, the entire upper and lower stroke is just the expansion and compression of the gas in the chamber, and there is no liquid lift. At this time, the “oil lock†phenomenon appears in the pump and it cannot work normally. When a gas lock is used, “hydraulic shocks†often occur, causing vibration of the rod pumping system and accelerating damage. For this purpose, the author explores the suitable pumping system for pressure-containing gas wells in gas-containing oil pump chambers from the analysis of the influence factors of the gas on the pumping pump efficiency, the air-locking conditions, and the improvement of the pumping efficiency. In the up-stroke, the fixed-valve and There will be accumulation of gas between the moving valves. If there is no change in the phase (ie, the oil in the pump chamber is not generated by the condensate gas when the pressure decreases), the pressure change in the pump chamber can be expressed approximately according to the state change law of the gas. A part of the stroke length occupied by the condensate gas in the Lb pump is the suction pressure of the pump, MPaS, the stroke of the pump, m; 3. The condition of the occurrence of the air lock is to reduce the free gas entering the pump. The fixed valve is as close to the bottom dead center of the stroke as possible without collision. That is, after the pump is seated, the blow-off prevention distance should be as small as possible, so as to increase the compression ratio of the oil pump. Good flow. Valve seat hole area is large, the inlet flow resistance is small, and at the same time, the flow area of ​​the valve ball opening is larger, which also improves the oil inlet efficiency; the flow valve resistance of the oil inlet valve is small, and the pump cavity can also be reduced. Gas separation to increase fullness. The separation of the dissolved gas in the well fluid reduces the oil-gas ratio of the well fluid before it enters the pump chamber, thereby improving pump efficiency. The improvement of the valve, the fixed valve, the cavity structure, and the compression method, and the use of a method of deflation near the upper (or lower) dead point to achieve both the prevention of air lock and the improvement of pump efficiency. Ways to Avoid Airlocks and Improve Pump Efficiency Bookmark4 Measures Analysis of Bookmark5 1 Avoiding Airlocks Many measures have been taken at home and abroad to prevent gas-containing oils. The above analysis is based on conventional pumping of gas-containing oil wells. Lock and improve its pump efficiency, the following for a variety of knots, when given the depth of the pump, the fluid pressure in the tubing to analyze and compare. Sliding shear sealing valve This valve has no ball, valve seat and valve cover. It adopts sliding shear sealing technology. It uses the downward movement of the valve stem to drive the hard disc of the sliding valve to slide downwards to force open the oil on the down stroke. The flow channel is forced to close with the valve stem on the up stroke, which is not affected by the fluid compression and avoids the air lock. The schematic diagram of the sliding shear seal valve is shown in Figure i. Figure i Slip shear seal valve principle - valve stem; 2 - pump cylinder; 3 - slide cut valve assembly; 4 - plunger The structure is designed with a buffer chamber, in the next stroke the fluid will fill the buffer chamber, so it can be Relieve impact on stroke. The valve can be used in gas-oil wells or below the packer. There are two kinds of anti-valve walking valves with ball plungers in the traveling valve with a ball plunger. The magnetic forced opening of the traveling valve [5. Used as a downstream moving valve, which adds a permanent magnet slider and a jack in the lower joint of the conventional downstream moving valve. On the upstroke, the permanent magnet slider and the top rod move downward relative to the plunger, and the dynamic valve is closed in the downstream of the magnetic force. In the down stroke, the permanent magnet slider and the top rod move upward relative to the plunger, and the downstream valve is opened in the action of the top rod. Although the anti-gas effect of this valve is obvious, the down resistance of the plunger is relatively large, and it needs to be used together with a weighted rod and a centralizer, and it is not suitable for heavy gas wells containing gas. The valve with a valve core is a moving valve. 6. The valve is also improved on the basis of a conventional traveling valve. It is a valve core added under the valve seat for the valve ball plunger. The valve core can slide within a certain range. , Has a certain anti-air lock effect. Two types of anti-air movement valve with valve ball top rod are used to slide the jacking ball to leave the valve seat when the ball is opened, which has a certain effect on the service life of the ball. When the oil is thick, the top rod descends. Difficulties, so it is not suitable for thick oil wells with easy sand cards and wax cards. The valve cover is welded by the valve cover, the valve body and the lower joint. The six oil circulation holes of the valve are good, and the angle of 5° is formed; the two spiral grooves on the inner wall of the valve also form an angle of 45° with the end surface of the valve body, and are aligned with the spiral of the valve cover. This valve changes the direction of the liquid flow into the pump chamber, enhances the ability to pass liquid, and increases the ability of the pump to control the compressible fluid. When the valve ball leaves the valve seat, the inlet flow area rapidly increases. The well fluid passes through the spiral groove in the cavity of the valve housing to generate a spiral movement, forming a cone-shaped liquid flow, which reduces the flow resistance of the liquid flow through the valve cover and does not cause large The pressure drop reduces the release of dissolved gas in the crude oil and the generation of condensate gas, thereby effectively preventing the air lock of the fixed valve and improving the pump efficiency. In the special anti-gas pump, the fixed valve is rarely improved, the fixed valve is generally used conventional ball. Spiral fixed valve covers are used in conjunction with anti-ball valves or anti-pneumatic pumps to provide better gas protection. The valve is well-guided and the ball's drift is small. When the well fluid flows from the bottom up through the chute, the fluid has a downward force on the valve ball so that the ball does not abut on the top of the ball chamber. This not only increases the flow area of ​​the oil outlet hole, but also when the plunger In the opposite direction, this force causes the valve ball to fall rapidly and reduce the pumping efficiency. (8. The oil and gas mixing valve fixed valve cover also has a streamlined flow characteristic, which can reduce the degree of turbulence entering the pump chamber and reduce the amount of crude oil. The escape of dissolved gas can effectively prevent the valve ball from lagging and improve pump efficiency. Groove-shaped closed-type ball valve can be applied to downstream valves and fixed valves. Increasing the diameter of the valve seat hole helps to reduce the resistance to oil flow at the inlet and also helps to prevent air lock. However, if the diameter of the through hole is too large, the impact velocity of the valve ball will increase. If it is too small, the lift distance of the valve ball will increase. Big. The diameter of the valve seat through-hole is 0.779 which is suitable for the diameter of the valve ball. 10. Because the impact energy of the valve ball on the valve seat has nothing to do with the quality of the valve ball, the large ball will only increase the hydraulic loss [8, so the large fixed valve is used to improve the pump efficiency. A useful way. The reasonable flow path of the valve should be able to guide and limit the maximum lift of the valve ball, as well as a reasonable valve cover structure, which will help improve pump efficiency. The pump has 2 sealing pairs and 2 working chambers, which are improved on the basis of conventional pumps. It is formed by the slender upper plunger and the larger diameter lower plunger in series, with a downstream motion at the lower end of the lower plunger. The valve has an upper outlet valve and an intermediate outlet valve at the lower end of the upper plunger. At the time of the down stroke, the oil and gas in the lower working chamber enters the upper working chamber to complete the first-stage compression; the oil and gas in the upper working chamber is again compressed during the up-stroke to complete the second-stage compression. This type of pump is suitable for high oil-gas ratio wells, and when the upstream valve is closed in the down stroke, it is beneficial to the downward movement of the plunger and the sucker rod is better in terms of force.8 It is also conducive to preventing gas thickening. When the ratio of oil and gas is large, the upper working chamber is much smaller than the lower working chamber. ! This kind of pump is also improved on the basis of conventional pumps. An annular valve and a seat are provided at the outlet of the pump cylinder. The up and down motion of the annular valve is limited to the valve cover. The through hole in the middle of the valve is in transition with the pull rod, and the opening and closing of the annular valve is completed by the up and down movement of the pull rod. When the pump is in the down stroke, the ring valve is closed, and the liquid column pressure is closed. In this way, the chamber pressure P between the ring valve and the downstream moving valve is rapidly reduced, the pumping efficiency is increased, and the downstream movable valve is easily opened, preventing the pump from opening. Air lock. From the outside, it is necessary to use a valve to open and close the special structure of the oil pump that is not affected by the gas. It mainly includes three aspects: Improvement of the valve body. The fixed valve adopts a large flow valve cover with spiral groove ball chamber; the moving valve adopts a sliding shear seal valve or an annular valve. Improvements to the cavity. Two-pole compression pump can be used; medium exhaust pump, gas-liquid mixture pump, double-stage carrier pump, etc. and anti-gas pump can be improved on the basis of conventional pump. During use, it is necessary to pay attention to sand control and strictly adjust the impact distance. The anti-air lock effect of the double-stage bearing rod pump is better. In oil wells with high oil-gas ratios, a special structure of anti-air lock pump is fully adopted, and the opening of the valve is not affected by the gas. Such as mechanical open and close pump or anti-gas thick pump, their anti-gas effect are better, can effectively prevent air lock, improve pump efficiency, but the processing is difficult, life is not easy to improve. The two-stage compression pump has a hydraulic feedback function and can be used in gas-containing thick oil wells.
Titanium Alloy Tube
GB/T 3620.1-94
GB/T 3624-95
GB/T 3625-95, TA1, TA2, TA8, TA8-1, TA9, TA9-1, TA10
ASTM A338, Gr1, Gr2, Gr3, Gr7, Gr9, Gr11, Gr12 etc.
Characteristic: Steel Pipe,Titanium Alloy Tube,Automotive Steel Tube,Precision Steel Automobile Tubes TORICH INTERNATIONAL LIMITED , https://www.steeltubepipechina.com
1. It has excellent corrosion resistance in many media
2. Low density, high strength and small equipment weight
3. The surface is smooth and clean without dirt, and the fouling coefficient is greatly reduced
Scope of application:
It is widely used in chemical industry, petroleum, metallurgy, light industry machinery, instrument, power generation, seawater desalination, medical equipment, chlor alkali salt making, electroplating, environmental protection, copper industry and other industries
Effect of Gas on the Pumping Efficiency of a Suction Pump and Countermeasures
Core Tips: Pumping pump efficiency and gas lock condition wells in gas-containing wells are ideal for pumping structures and ways to prevent gas heM)lishin=1H33.Allrightsreserved. Oil wells with low fluid levels in the middle and later stages of oilfield development, especially High gas-liquid ratio wells,