RU2665007C1 - Method of pulsing well operation and device for implementation of method - Google Patents

Abstract

FIELD: oil and gas industry.SUBSTANCE: group of inventions refers to the oil industry and can be used for extraction from the wells of a liquid with increased gas content by pumping with blade pumps. Method of pulsating operation of a well with a vane pump includes a periodic repetition of the cycles of pumping liquid into the lifting pipe string and accompanied by the turbine rotation of the working wheels of the pump draining liquid from the column through the pump into the well when the pump is disrupted. Turbine rotation of the working wheels of the pump is carried out without changing the direction of rotation of the wheels. As the pump is filled with liquid drained from the column through the pump, pump self-pickup is performed. After this, they proceed to the next cycle of fluid supply by the pump, then the cycles are repeated, alternating the pump with the pump from the well and filling the pump in the process of draining liquid from the column while simultaneously filling the well with liquid with an ongoing inflow from the reservoir. Thus, an autonomous pulsating mode of operation of the "formation-well-pump" system.EFFECT: inventions are aimed at overcoming the negative effect of reverse turbine rotation of the pump working wheels during the drainage of liquid from the riser pipe through the pump in the well for the stability of the vane pump, including in conditions of increased gas content at the pump intake.3 cl, 1 dwg

Description

FIELD OF THE INVENTION

The invention relates to the oil industry and can be used in the production of wells with high gas content by pumping by vane pumps.

State of the art

There is a method of operating wells, which consists in periodically pumping fluid from the well with a subsequent accumulation period, while the processes of accumulating and pumping fluid from the reservoir are carried out under conditions of sealing the annulus of the well [Schurov V.I. Technology and equipment for oil production. - M .: Nedra, 1983, p. 414-415].

The disadvantages of this method are the large losses of oil production compared with the continuous operation, due to the fact that the average integral depression on the reservoir during periodic operation is less than the depression during continuous operation.

Also known is a submersible multistage centrifugal pump containing working stages located in a cylindrical casing, each of which is made of a blade impeller mounted on the pump shaft and a fixed blade guide apparatus [AS No. 1763719 USSR, IPC F04D1 / 06, published 1992.09.09].

The disadvantage of this pump is unstable operation when pumping a gas-liquid mixture.

The closest in technical essence to the claimed solution is a method of pulsed operation of a well with a vane pump, which includes periodic repetition of the cycles of fluid supply by the pump to the column of lifting pipes and accompanied by turbine rotation of the impellers of the pump draining the liquid from the column of lifting pipes through the pump into the well when the pump is disrupted. [AS No. 1262026 of the USSR, IPC E21B43 / 00, published.1986.10.07].

A feature of the known method is the pulsating nature of the operating mode of the well with a variable direction of fluid flow in the column of lifting pipes up from the pump to the wellhead when the fluid is supplied by a vane pump to the column of lifting pipes and down from the wellhead into the annulus during the discharge of fluid through the pump into the well. This mode has a positive effect on the condition of the column of lifting pipes, reducing the risk of deposits of mechanical impurities, salts and other deposits on the surface of the pipes and pump. The disadvantage of this method can be attributed to the fact that during the discharge of fluid into the well, the rotation of the pump changes to the reverse turbine rotation of the impellers of the pump. Therefore, for the success of each next start of the pump, it is necessary to disconnect the electric motor from the voltage of the field electric network for the period of draining the liquid from the riser pipes into the well in each cycle. As a result, the flow rate of the well is reduced, and frequent starts of the pump adversely affect the reliability of the pump and electric motor.

As a prototype of a device for implementing the proposed method of pulsed well operation with a vane pump, a multi-stage vane pump is selected, consisting of housings in which packages of stages of impellers, fixed guide vanes and shafts are placed on which impellers of stages are mounted, with the possibility of rotation together with shafts, in this case, the packages of stages consist of stages of various types, designed for different feeds, and the steps for large feeds are placed at the inlet section of the pump, then towards the exit stage are set to smaller feed in descending order of their rated values [Testimony to the PM of the Russian Federation №7459, IPC F04D 13/00, opubl.1998.08.16].

The disadvantage of the known device is the instability of operation with increased gas content at the intake of the pump and the reverse turbine rotation of the pump impellers [A. Bogdanov A. Submersible centrifugal electric pumps for oil production (calculation and design) - M., Nedra, 1968, p. 263 - 264., The dissertation for the degree of candidate of technical sciences. The author - Labah Nula "Development of methodological and technological solutions for the selection of upstream modules of an electric centrifugal pump in complicated well operating conditions." Gubkin Russian State University of Oil and Gas (National Research University), - Moscow, 2016, p. 34.].

Disclosure of invention

The technical result, to which the claimed invention is directed in terms of the method and device, is to overcome the negative effect of the reverse turbine rotation of the pump impellers during the discharge of liquid from the column of lifting pipes through the pump into the well on the stability of the vane pump, including in conditions of high gas content at the pump intake.

The specified technical result in terms of the method is achieved by the fact that according to the claimed method of pulsed well operation using a vane pump, which includes periodic repetition of the fluid supply cycles of the pump to the column of lifting pipes and accompanied by turbine rotation of the impellers of the pump, draining the liquid from the column of lifting pipes through the pump into the well when the supply is interrupted pump, while the turbine rotation of the pump impellers is carried out without changing the direction of rotation of the pump impellers, and as we fill the wasp with the liquid discharged from the column of lifting pipes through the pump into the well, self-picking up the pump supply is carried out, then the next cycle of pumping liquid by the pump into the column of lifting pipes is carried out, and then the cycles are repeated, alternating pumping liquid from the well from the well and filling the pump during liquid discharge from columns of lifting pipes while filling the well with a fluid with a continuous inflow from the reservoir, thereby performing an autonomous pulsating mode of operation of the system "reservoir - well - n asos. "

In terms of the device, the indicated technical result is achieved by the fact that the device for implementing the inventive method of pulsating well operation with a vane pump, which is a multi-stage vane pump, consisting of housings in which packages of stages of impellers, fixed guide vanes and shafts are mounted on which impellers are mounted steps, with the possibility of rotation together with the shafts, while the packages of steps consist of steps of various types, designed for different feeds, and steps Long audio feed placed at the entrance of the pump, then towards the outlet stage set to smaller feed in descending order of their nominal values (conical layout), and the output arrangement conical package installed stages nominal rotational direction opposite pump impellers. This package of stages of the opposite nominal direction of rotation of the pump impellers is equipped in a predetermined number of stages with large nominal feeds and a large turbine torque sufficient to maintain the direction of rotation of the pump impellers unchanged in the process of draining the liquid from the column of lifting pipes through the pump into the well.

The proposed method and device have new features that are absent in the selected prototypes, which indicates the compliance of the claimed objects with the criterion of "novelty."

Description of the drawing

The drawing shows a layout of a submersible pump installation in a well drilled on an oil reservoir. The pump installation, by means of which the claimed method of pulsed well operation is carried out, comprises a multi-stage vane pump 3 located in the well 1 on the column 2 of lifting pipes, driven by an electric motor 4, the energy of which is supplied via cable (not indicated by the position). In the housing of a multi-stage vane pump 3, packages of stages of impellers, fixed guide vanes and shafts are placed on which impellers of stages are mounted, with the possibility of rotation together with shafts, while stage packages consist of stages of various types, designed for different feeds, and stages for large feeds are placed in package 5 at the inlet section of pump 3, then towards the output steps are set to lower feeds in decreasing order of their nominal values (package of 6 stages of conical arrangement and). The pump kit 3 complements the package of 7 stages of the opposite nominal direction of rotation of the impellers. This package of 7 steps of the opposite nominal direction of rotation of the impellers is installed at the output of the conical package 6 and is equipped with a given number of steps with large nominal feeds and a large turbine torque sufficient to maintain the direction of rotation of the impellers of pump 3 during the discharge of liquid from the lifting column pipes through the pump 3 to the well 1.

The implementation of the invention

The method of pulsating well operation with a vane pump according to the present invention is as follows. The pump 3 is started by connecting the electric motor 4 through the power supply cable to the field network to the required voltage of the nominal frequency and pumping the formation fluid with the pump 3. Gradually, the liquid at the receiving level of the pump 3 enters the state of the gas-liquid mixture, enters the stages of the packet 5 and is compressed, then in the stages of the packet 6, the working pressure and pump flow 3 develops. At the output of the package 6 of the conical arrangement of the pump 3, the flow of pumped products enters the stage of the package 7, from which it is supplied to the column 2 detachable pipes of the well 1. The liquid is pumped by pump 3 along the column 2 of the lifting pipes at the wellhead 1 until the head is cut off and pump 3 is fed, after which the fluid from the column 2 of the lifting pipes is drained through the pump 3 through the pump 3 to the well accompanied by turbine rotation of the impellers of the pump 3 1. Due to the fact that the nominal direction of rotation of the impellers of the package 7 is opposite to the nominal direction of rotation of the impellers of the packages 5 and 6 of the conical arrangement of the pump 3, and the turbine torque developed by the impellers pa Seta 7 of pump 3 is greater than the turbine torque of the impellers of package 5 and packages 6, during the process of draining the liquid from the column 2 of the riser pipes through the pump 3 into the well 1, the direction of the actual rotation of the impellers of the pump 3 remains unchanged by the electric motor 4. As it fills up the stages of the package 7, 5 and 6 of the pump 3, the liquid drained from the column 2 of the lifting pipes into the well 1, perform a self-pickup of the pump 3 and proceed to the next cycle of supplying the liquid by the pump 3 to the column 2 of the lifting pipes. Next, the cycles are repeated, alternating pumping of the liquid by pump 3 from the well 1 and filling of the pump 3 with liquid from the column 2 of the lifting pipes while filling the well 1 with the liquid by a continuous inflow from the reservoir, thereby performing an autonomous pulsating mode of operation of the "reservoir - well - pump" system.

In General, the claimed invention is aimed at increasing the stability of the operating mode of the system “reservoir - well - pump" and practically does not require additional costs, because, in the proposed layout of the vane pump in a new combination, standard vane stages of the left and right nominal direction of rotation of the impellers of the pump are used. A systematic change in the direction of fluid flow through the pump improves the cooling of the pump, and thanks to the refusal of complex operations to control and regulate the frequency of the electric motor voltage, pump control is simplified. Essentially, the well mode is tuned for fluid flow from the formation independently. In addition, no upstream devices are required to be installed at the pump inlet, as well as depth valves at the pump outlet and in the riser string.

Claims (3)

1. The method of pulsed operation of the well with a vane pump, comprising periodically repeating the cycles of pumping fluid into the column of lifting pipes and accompanied by turbine rotation of the impellers of the pump draining the liquid from the column of lifting pipes through the pump into the well when the pump is disrupted, characterized in that the turbine rotation of the impellers the pump is carried out without changing the direction of rotation of the impellers of the pump, and as the pump is filled with liquid discharged from the column of lifting pipes through the pump into the well, self-pickup of the pump supply takes place, after that they go on to the next cycle of pumping fluid into the riser string and the cycles are repeated, alternating pump pumping out of the well and filling the pump in the process of draining the liquid from the riser string while filling the well with fluid with a continuous flow from the reservoir thereby carry out an autonomous pulsating mode of operation of the system "reservoir - well - pump". 2. A device for implementing the method of pulsed operation of a well with a vane pump, which is a multi-stage vane pump, consisting of housings in which packages of stages of impellers, fixed guide vanes and shafts are placed on which impellers of stages are mounted, with the possibility of rotation together with the shafts, in this case, the packages of stages consist of stages of various types, designed for different feeds, and the steps for large feeds are placed at the inlet section of the pump, then towards the outlets dy installed stage feed into smaller in descending order of their nominal values (conical arrangement), characterized in that the conical output stage layout package installed opposite nominal direction of rotation of the pump impellers. 3. The multi-stage vane pump according to claim 2, characterized in that the package of steps of the opposite nominal direction of rotation of the impellers of the pump is completed in a predetermined number of steps with large nominal feeds and a large torque of the turbine sufficient to maintain the direction of rotation of the impellers of the pump during discharge fluid from the column of lifting pipes through the pump into the well.

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