RU2112890C1 - Pumping unit for lifting liquid from oil well - Google Patents

Abstract

FIELD: lifting liquids from oil wells. SUBSTANCE: pumping unit includes cylinder with lower suction valve located in lower portion coaxially relative to cylinder. Center suction valve is located above lower one eccentrically relative to axis of cylinder. Upper suction valve is located above, coaxially relative to center suction valve. Low-pressure intake chamber is located at inlet of lower suction valve; its upper portion is connected with center suction valve by means of connecting pipe. Pumping unit is provided with additional high-pressure intake chamber located below low-pressure intake chamber and connected with it by means of lifting pipes. Upper portion of high-pressure intake chamber is connected with well through outlet valve. EFFECT: enhanced efficiency of operation of oil wells at high gas-oil factor and low dynamic level where existing pumping units operate at low efficiency. 1 dwg

Description

 The technical solution relates to the oil industry and can be used to increase the working flow rate of oil wells, a particularly higher effect can be achieved in wells with a high gas-oil factor and low dynamic level.

 There are a number of designs of deep sucker rod pumps designed for pumping gas-liquid mixtures from an oil well. One of the most common designs is the design of a pump with stepwise compression of the gas-oil mixture inside the cylinder, divided by a differential plunger into two parts, where the lower part is a low-pressure stage and the upper part is a high-pressure stage (I. Muravyev et al. Pumping operation of wells abroad. - M .: Nedra, 1967, p. 55-62, Fig. 45a).

 A number of designs are referred to single-chamber pumps with single-stage compression of a gas-liquid mixture in a cylinder.

 Firstly, it is a deep-well sucker-rod pump with an eccentrically located suction valve (SU, ed. Certificate No. 545769, class F 04 B 47/02, 1977). Due to the design feature, the influence of the dead zone of the cylinder on the operation of the pump is excluded, which ensures high efficiency when pumping gas-liquid mixtures. Secondly, it is a deep-well sucker-rod pump with lower and upper suction valves, the upper suction valve being located eccentrically to the axis of the cylinder (SU, author certificate N 1323743, class F 04 В 47/02, 1987). In the practice of oil production, this design is designed to pump out waterlogged products from oil wells. This technical solution is the closest to the proposed.

 The objective of the invention is the creation of a device for lifting liquid to the surface, which due to the higher concentration of free gas in the cylinder cavity will allow more efficient use of associated gas energy and thereby reduce energy consumption for raising the liquid.

 The problem is solved due to the fact that the pump installation, containing a cylinder with three suction valves (lower, middle, upper) and a low pressure receiving chamber, is additionally equipped with a high pressure receiving chamber located under the low pressure chamber connected by elevator pipes, moreover the upper part of the receiving chamber of the high pressure is connected to the well through an exhaust valve.

 The drawing shows a diagram of a pumping unit for lifting fluid from an oil well, where cylinder 1 is equipped with a plunger 2 with a discharge valve 6, a lower suction valve 3 located on the axis of the cylinder 1, a middle suction valve 4 located above and eccentrically to the axis of the cylinder 1, the upper suction a valve 5 located above and coaxially with the middle suction valve 4. A low pressure receiving chamber 7 is attached to the cylinder 1 from the bottom, the upper part of which, in turn, is connected to the middle suction valve 4 pipe 8. Under the low-pressure chamber 7 there is a high-pressure receiving chamber 9 connected to the low-pressure receiving chamber 7 by lift pipes 11, and the upper part of the high-pressure receiving chamber 9 is connected to the well through an exhaust valve 10.

 The operation of the pumping unit for lifting liquid from an oil well is as follows.

Assume that the plunger 2 is in its lowest position, i.e. below the plunger 2 is the dead zone of cylinder 1, where there is oil without gas, and the pressure in this part of cylinder 1 is equal to the pressure at the pump outlet. When the plunger 2 moves up, the discharge valve 6 closes, and the pressure in the cylinder 1 begins to decrease. Since oil without gas is located under the plunger 2, when the plunger 2 moves up, the pressure in the cylinder 1 will immediately drop to the pressure at the intake of the lower suction valve 3. The lower suction valve 3 will open, and oil from the low pressure receiving chamber 7 will begin to flow into cylinder 1. Oil is supplied from the low-pressure receiving chamber 7 to the cylinder 1 through a special channel, and the gas through the connecting pipe 8 is received by the middle suction valve 4. The process of filling the cylinder 1 with oil will continue until eye lower end of the plunger 2 will not rise to the average location of the suction valve 4. At this moment in a low pressure receiving chamber 7 will flow with the gas oil from the tubing 11 which when turning the jet flow 180 is released from the ^o associated gas. The same process occurs in the high-pressure receiving chamber 9, where soda oil supplied from the well is freed from free gas, the oil from the high-pressure receiving chamber 9 will be directed to the lift pipes 11, and the gas through the exhaust valve 10 will enter the annulus of the well .

 At the moment when the lower end of the plunger 2 reaches the installation site of the middle suction valve 4, the middle suction valve 4 opens and gas begins to flow into cylinder 1 from the upper part of the low-pressure receiving chamber 7. In this case, the pressure in cylinder 1 will increase by a certain amount and the lower suction valve 3 closes. The flow of gas into the cylinder 1 from the low pressure receiving chamber 7 will continue until the lower end of the plunger 2 rises to the location of the upper suction valve 5. At this point, the suction valve 5 opens and gas from the annulus of the well begins to flow into the cylinder 1 , while the pressure in the cylinder 1 will increase by a certain amount and the average suction valve 4 will close. The flow of gas into the cylinder 1 from the annulus of the well will be until the plunger 2 will not occupy its highest position.

 With the upper position of the plunger 2, the upper and middle parts of the cylinder 1 will be filled with gas, the lower - with oil. The dividing line is the installation location of the middle suction valve 4.

 When the plunger 2 moves down, the upper suction valve 5 closes and the pressure in the cylinder 1 starts to rise. At the moment of equal pressure above and below the plunger 2, the discharge valve 6 opens, and gas begins to flow into the cavity of the elevator pipes 11.

 The flow of gas into the lift pipes 11 will continue until the plunger 2 reaches the liquid-gas separation line in the cylinder 1. Subsequently, when the plunger 2 moves downward, oil will flow into the lift pipes 11. This process will continue until the plunger 2 reaches its lowest position.

 When the plunger 2 moves up, the cycle of operation of this installation is repeated.

Claims (1)

 A pumping device for lifting liquid from an oil well, comprising lift pipes, a cylinder with a lower suction valve, an eccentrically located middle suction valve and a low pressure receiving chamber, characterized in that the cylinder is additionally equipped with an upper suction valve located above and coaxially with the middle suction valve and a high pressure receiving chamber located under the low pressure chamber connected by elevator pipes, the upper part of the high pressure receiving chamber being connected Nene with a well through an exhaust valve.