RU2847797C1 - Method for determining the flow rate of the upper layer of a well during the operation of a single-lift installation for simultaneous separate operation with a sucker rod pump - Google Patents

Abstract

FIELD: oil production industry.

SUBSTANCE: invention can be used in the operation of wells on multi-layer oil deposits. The method for determining the flow rate of the upper layer of the well during the operation of a single-lift installation for simultaneous separate operation with a sucker rod pump includes starting the installation and measuring the total production of the upper and lower layers at the surface. The lower layer is shut off using a side suction valve located on the deep sucker rod pump, consisting of a seat, a metal ball and a metal sleeve to which an electric magnet is attached with a cable and an opening corresponding to the inner diameter of the valve seat. Electricity is supplied from the control panel to the electric magnet, which is designed to press the metal ball against the seat through the metal sleeve with a force exceeding the pressure of the lower layer. The side suction valve is connected by a fibreglass receiving pipe to the tail of the fibreglass pump-compressor pipe string, which is connected to a packer separating the upper and lower formations. The body of the side suction valve and the tailpiece are made of fibreglass. The deep well pump is located in a fibreglass casing. The flow rate from the upper formation is measured.

EFFECT: reduction of time and labour costs for upper formation exploration when operating a single-lift unit for simultaneous separate operation without stopping the well pump.

1 cl, 1 dwg

Description

The proposed invention relates to the oil production industry and can be used in the operation of wells in multi-layer oil deposits.

A method is known for determining the flow rate of the lower formation of a well during operation with a single-lift unit for simultaneous-separate operation with a sucker-rod pump by determining the flow rate of the upper formation by restoring the level in the annular space, and the lower one - as the difference between the total and upper flow rates (Simultaneous-separate operation of two formations at OAO Tatneft / Takhautdinov Sh.F., Ibragimov N.G. et al. - Oil Industry - 2006, No. 3 - pp. 58-61) and calculating the distribution of the total flow rate proportional to the plunger stroke before and after the "step" using a dynamometer chart.

The disadvantages of this method are that the pump method does not provide accurate data on the formation flow rates and is approximate in nature with an error of approximately 10%, while it is necessary to shut down the well until the liquid level is restored with a loss of fluid production, and if the difference in pressure between the producing formations is minimal, there may not be a “step” on the dynamometer chart (the activation of the side suction valve BVK), in which case it is necessary to top up the fluid in the annular space, as well as the presence of gas in the pump cylinder and the method of constructing a theoretical dynamometer chart can lead to an error.

A method is known for studying the lower formation of a well during the simultaneous and separate operation of two formations separated by a packer using a sucker-rod pump (variants) (RU patent No. 2289022, IPC E21B 49/00, E21B 43/14, published 12/10/2003, Bulletin No. 34), where during operation the product of the lower formation is selected through a column of hollow rods, and the reduction of the back pressure on the productive formation is carried out by lifting the liquid in the hollow rods using a piston with a check valve, driven from the surface by a flexible traction element, with subsequent monitoring of the pressure recovery.

The disadvantage of this method is that during the study it is necessary to stop the installation, install a lubricator and a winch, and after swabbing, measure the dynamics of the level in the hollow rods with losses in fluid pumping and a significant loss of time for the study.

A method closer in technical essence and the achieved result is one for studying a well during its operation with a sucker rod pumping unit with the wellbore isolated above the productive formation by a packer (RU patent No. 2658085, IPC E21B 43/14, E21B 47/10, F04B 47/02, published on 19.06.2018, Bulletin No. 17), where the measurement of formation production includes measuring the total production of the upper and lower formations at the daily production and subsequent shutting in of the well with lifting the rod string by an amount sufficient to break the bushing off the anchor with the pump plunger, after which the unit is put into operation with the measurement of the fluid flow rate of the lower formation.

The disadvantages of this method are:

- before conducting the study, it is necessary to stop the installation, which leads to a loss of fluid production;

- before conducting the study, it is necessary to re-adjust the plunger with the help of PRS specialists or a specialized team;

- when using this installation, the service life of the anchor elastic springs is comparatively short.

The technical objectives of the proposed method are to reduce the time and labor costs for research of the upper formation during the operation of a single-lift unit for simultaneous-separate operation without stopping the borehole pump by shutting off the lower sub-packer formation without involving specialized teams and reducing the loss of well fluid flow rate at the daylight surface.

Technical problems are solved by a method of determining the flow rate of the upper layer of a well during the operation of a single-lift unit for simultaneous-separate operation with a sucker rod pump, which includes starting the unit into operation and measuring the total production of the upper and lower layers on the daylight surface.

What is new is that the lower formation is shut off using a side suction valve located on the sucker-rod pump, consisting of a seat, a metal ball and a metal sleeve, to which an electric magnet with a cable and an opening corresponding to the internal diameter of the valve seat is attached, by supplying current from the control panel to the electric magnet, configured with the possibility of pressing the metal ball to the seat through the metal sleeve with a force exceeding the pressure of the lower formation, while the side suction valve is connected by a receiving tube made of fiberglass to the tail of the tubing column made of fiberglass, connected to a packer separating the upper and lower formations, the body of the side suction valve and the tail are made of fiberglass, and the sucker-rod pump is located in a fiberglass casing, then the flow rate from the upper formation is measured.

The figure shows a diagram of the operation of a single-lift installation for the simultaneous-separate operation of a sucker-rod pump with a side valve, additionally equipped with an electric magnet.

A sucker rod pump 3 in a fiberglass casing 4, connected to a fiberglass tailpiece 5 and a packer 6 separating the upper layer 7 and the lower layer 8 (Fig.), is lowered into a well with a fiberglass casing 1 on a fiberglass tubing string (TUB) 2. On the sucker-rod pump 3 there is a body of the side valve 9, which includes a valve seat 10, a ball 11, a metal sleeve 12, to which an electric magnet 13 with a cable 14 is attached, connected to a receiving tube made of fiberglass 15. The electric magnet 13 is provided with an opening corresponding to the internal diameter of the seat 10 of the valve 9. The reciprocating movement of the plunger 16 is carried out by a drive (not shown in the figure) with the help of a column of rods 17 made of fiberglass, wherein the liquid from the well enters through openings 18 and 19.

The method is carried out as follows.

To enhance the electromagnetic field's impact, casing string 1, tubing 2, liner 5, rod string 17, side valve body 9, and receiver tube 15 are made of fiberglass. Sucker rod pump 3 is housed in a fiberglass casing, and packer 6, which separates upper formation 7 from lower formation 8, is self-swelling (e.g., RU Patent No. 171928, IPC E21B 33/12).

After the sucker rod pump 3 is put into operation, the well fluid from the upper layer 7 enters the pump 3 through the openings 18 when the plunger 16 moves upward with the help of the fiberglass rods 17, and when the plunger 16 passes the body of the side valve 9 with the opening 19, the well fluid from the lower layer 8 enters the cylinder through the receiving tube 15, the electric magnet 13 with the opening corresponding to the inner diameter of the valve seat 10, the metal sleeve 12 and the valve seat 10. The ball 11 is raised.

During the exploration of the upper formation, with the downward movement of the plunger 16, the ball 11 falls onto the valve seat 10, and at this time, current is supplied from the control panel on the earth's surface through cable 14 to the electric magnet 13, which, in turn, through the metal sleeve 12 and the valve seat 10, presses the ball 11 with a force exceeding the pressure of the lower formation 8. Due to the fact that the sucker-rod pump 3 is located in a fiberglass casing 4 and the body of the side valve 9 with the receiving tube 15 are made of fiberglass, the magnetic force will act maximally on the metal ball 11. In this position of the ball 11, production is carried out only from the upper formation 7 with flow rate measurement.

After completion of the study, the supply of electric current through cable 14 to electric magnet 13 is stopped from the control panel (not shown in the figure) and the installation begins to operate in the standard mode, as when operating a single-lift installation for simultaneous-separate operation.

Production continues from two layers, with the total flow rate measured at the surface. The flow rate of the lower layer 8 is calculated by subtracting the flow rate of the upper layer 7 from the total well flow rate.

The proposed method provides a significant simplification of well surveys with a single-lift installation for the simultaneous-separate operation of an oil well with a sucker rod pump and a reduction in labor intensity, since, unlike analogs during periodic surveys, the work is performed by one specialist, there is no need to stop the well operation, which leads to the loss of well fluid, and there is no need to involve a specialized team or a well service team.

Claims (1)

A method for determining the flow rate of the upper formation of a well during the operation of a single-lift unit for simultaneous and separate operation with a sucker-rod pump, including starting the unit into operation and measuring the total production of the upper and lower formations on the day surface, characterized in that the lower formation is shut off using a side suction valve located on the sucker-rod pump, consisting of a seat, a metal ball and a metal sleeve, to which an electric magnet with a cable and an opening corresponding to the internal diameter of the valve seat is attached, by supplying current from the control panel to the electric magnet, configured to press the metal ball to the seat through the metal sleeve with a force exceeding the pressure of the lower formation, wherein the side suction valve is connected by a receiving tube made of fiberglass to the shank of a column of tubing made of fiberglass, connected to a packer separating the upper and lower formations, the body of the side suction valve and the shank are made of fiberglass, and the sucker rod pump is located in a fiberglass casing, then the flow rate from the upper layer is measured.