RU2848520C1 - Installation of rod pump with parallel pipe columns for operation of wells with increased sand carry - Google Patents

Abstract

FIELD: pumps.

SUBSTANCE: invention relates to a sucker rod pump installation with parallel pipe columns for operating wells with increased sand carryover. The installation consists of a downhole sucker rod pump (DSP) lowered on the main column of pump-compressor pipes (PCP) and capable of being driven through a column of sucker rods. An additional lift pipe column with a check valve at the bottom is located parallel to the main PCP column. The main tubing string is filled with degassed low-viscosity oil with a density lower than that of the well production, covered at the top and connected to the additional lift string. The main tubing string is equipped with a pipe with a reduced cross-section and a polished inner surface, installed above the parallel anchor assembly. Inside the pipe there is a polyurethane sleeve with cups facing the mouth of the. The sleeve is installed on the pump rod column and connected to the DSP plunger via an automatic coupling. The DSP cylinder is equipped with drain holes. Below the DSP cylinder, a perforated pipe and a tubing container with a plug are installed in series. The holes in the perforated pipe are covered with a cup-shaped half-cover, with the open part facing the wellhead, in the coupling between the pipes of the additional lift column. Above the check valve, there is a metal ring with a fixed inner pipe, plugged at the top and equipped with slotted holes on the side surface in the upper part. Above the inner pipe, the additional lift column is equipped with a drain valve.

EFFECT: increased reliability and efficiency of the rod pump installation.

1 cl, 1 dwg

Description

The invention relates to the oil producing industry, in particular to the extraction of well products with increased sand and mechanical impurities by deep well sucker rod pumps.

A well-known deep-well pumping unit for the production of high-viscosity oil is (RU patent No. 136081, IPC E21B 43/00, published on 27.12.2013 in bulletin No. 36), consisting of a sucker-rod borehole pump, capable of being driven through a column of pump rods, a column of tubing, a sand anchor at the pump intake, a packer connected to a container of the sand anchor through a perforated pipe, wherein a check valve is installed between the perforated pipe and the packer, and below the packer there is an additional sand anchor with a container.

A disadvantage of the installation is that sand gets into the gap of the plunger pair from above when the well is stopped, which leads to the plunger jamming in the cylinder.

A device for pumping out carbonated liquid is known (SU Patent Application No. 866133, IPC E21B 43/00, published on September 23, 1981 in Bulletin No. 35), comprising a submersible sucker-rod pump with a separator shank connected to the pump intake, and a casing with a shank and a gas release valve, wherein the casing is located concentrically to the submersible sucker-rod pump, secured in its upper part, and the gas release valve is located at the casing attachment point. The shank-separator is equipped in the lower part with a mesh with a mesh size of 0.1-0.2 mm.

A disadvantage of the device is the low reliability of protection against mechanical impurities due to the rapid clogging of the mesh on the tailpiece, which leads to the need to replace the pump.

The closest to the proposed one is the installation of a sucker rod pump with parallel pipe strings for the operation of wells with increased sand production (patent RU No. 2815669, IPC E21B 43/16, published on 19.03.2024 in Bulletin No. 8), consisting of a borehole sucker rod pump (BSRP) lowered on a string of tubing and having the ability to be driven through a string of sucker rods, the installation is equipped with a tubing string with a check valve in the lower part, located parallel to the tubing string, while the tubing string is filled with a liquid of a density less than that of the well product, is blocked in the upper part and communicates with the tubing string through a parallel anchor unit located directly above the BSRP, equipped with a protective sleeve.

The disadvantages of this installation are:

- low reliability due to clogging of the check valve by settling sand during stops;

- poor device performance due to malfunctions caused by extended shutdowns. After extended shutdowns, the amount of settled mechanical impurities can be so large that it prevents the check valve from opening when the unit is restarted;

- Difficulty in servicing the device. Lifting an additional string of tubing with fluid spilling out at the wellhead, as the check valve prevents fluid from draining from the tubing string during lifting, increases repair time, leads to contamination of the area around the well, and deteriorates working conditions for personnel.

- in addition, well fluid will gradually penetrate through the protective sleeve into the tubing string, which can lead to the rod string hanging due to high viscosity of the well product or the accumulation of free gas in the upper part of the tubing string, which will lead to insufficient lubrication of the wellhead rod, wear of the sealing cuffs, depressurization of the gland and contamination of the area around the well.

The technical objectives are to increase the reliability and efficiency of the sucker rod pump installation by preventing the ingress of settling sand from the tubing string into the gap of the pump plunger pair, into the internal cavity of the plunger and onto the discharge valve when the well is shut in, to increase the reliability of the check valve and to eliminate complications when lifting downhole equipment, to prevent the penetration of well products into the main tubing string to prevent the rod string from hanging or the wellhead seal from becoming depressurized.

The technical problems are solved by installing a sucker rod pump with parallel pipe strings for operating wells with increased sand production, consisting of a downhole sucker rod pump (SRP), lowered on the main tubing string (TU) and capable of being driven through the sucker rod string, an additional tubing string with a check valve in the lower part, located parallel to the main TU string, the main TU string is filled with degassed low-viscosity oil, with a density lower than that of the well product, blocked from above, and communicated with the additional tubing string through a parallel anchor unit located directly above the SRP and equipped with a protective sleeve.

What is new is that the main tubing string is equipped with a branch pipe with a reduced cross-section and a polished inner surface, installed above the parallel anchor unit, a polyurethane cuff with cups facing the wellhead with their open part, is placed inside the branch pipe, wherein the cuff is installed on the string of pump rods and is connected to the plunger of the sucker rod pump through an automatic coupling, the cylinder of the sucker rod pump is made with drain holes, below the cylinder of the sucker rod pump a perforated branch pipe, a container made of tubing with a plug are installed in series, wherein the holes of the perforated branch pipe are covered with a cup-shaped semi-casing facing the wellhead with its open part, in the coupling connection between the pipes of the additional tubing string, a metal ring is installed above the check valve, on which the inner branch pipe is fixedly fixed, plugged at the top, provided with slotted holes on the side surface in the upper part, above the inner branch pipe the additional tubing string is equipped with a drain valve.

The figure shows a sucker rod pump installation with parallel pipe strings for operating wells with increased sand production, where the main tubing string is 1, the additional lifting tubing string is 2, the sucker rod pump is 3, the cylinder is 4, the plunger is 5, the sucker rod string is 6, the check valve is 7, the degassed low-viscosity oil is 8, the parallel anchor unit is 9, the protective sleeve is 10, the branch pipe is 11, the polyurethane cuff is 12, the automatic coupler is 13, the drain holes in the cylinder are 14, the perforated branch pipe is 15, the half-casing is 16, the tubing container is 17, the plug is 18, the wellhead rod is 19, the wellhead gland is 20, the inner branch pipe is 21, the drain valve is 22.

The essence of the invention.

A sucker rod pump system with parallel tubing strings for operating wells with increased sand production consists of a sucker rod pump (SRP) 3, lowered on a main tubing string (1) and capable of being driven through a sucker rod string (6), an additional tubing string (2) with a check valve (7) at the bottom, located parallel to the main tubing string (1), the main tubing string (1) filled with degassed low-viscosity oil (8), whose density is lower than that of the well product. The main tubing string (1) is closed at the top and communicates with the additional tubing string (2) through a parallel anchor assembly (9), located directly above the SRP 3 and equipped with a protective sleeve (10).

The main tubing string 1 is equipped with a branch pipe 11 with a reduced flow section and a polished inner surface, installed above the parallel anchor unit 9.

A polyurethane cuff 12 with cups facing the wellhead with their open portions (not shown in the figure) is located inside the nozzle. The cuff 12 is mounted on the sucker rod string 6 and connected to the plunger 5 of the sucker rod pump 3 via the automatic coupling 13. The cuff 12 prevents well fluid from penetrating into the main tubing string 1 to prevent the formation of a highly viscous emulsion and the suspension of the sucker rod string 6.

Cylinder 4 of the SShN 3 is made with drain holes 14.

Below cylinder 4 of the SSHN 3, a perforated nozzle 15 and a tubing container 17 with a plug 18 are installed in series. The perforated holes of nozzle 15 are covered by a cup-shaped half-casing 16, with its open end facing the wellhead. When the fluid flow reverses in the area of the open end of half-casing 16, free gas bubbles separate and float to the surface, preventing them from entering the main tubing string 1, ensuring the necessary lubrication of the wellhead rod and preventing depressurization of the wellhead seal.

In the coupling connection between the pipes of the additional elevator column 2, above the check valve 7, a metal ring is installed (not indicated in the figure), on which the internal branch pipe 21 is fixedly fixed, plugged at the top, equipped with slotted holes (not indicated in the figure) on the side surface in the upper part.

Above the internal pipe 21, the additional elevator column 2 is equipped with a drain valve 22.

The equipment is lowered as follows.

First, a container made of tubing 17 with a plug 18, a perforated branch pipe 15 with a half-casing 16, and a sucker rod pump 3 with a protective sleeve 10 are lowered onto the main tubing string 1. Then, a string of pump rods 6 with a cuff 12 and an automatic coupler 13 is lowered, and the plunger 5 is connected to the rod string 6 using an automatic coupler 13, while the cuff 12 is installed inside the branch pipe 11 with a reduced flow section and a polished inner surface. The diameter of the cuff 12 is smaller than the internal diameter of the main tubing string 1, therefore, during lowering, pistoning and wear of the cuff 12 do not occur, but the diameter of the cuff 12 is 1-2 mm smaller than the internal diameter of the branch pipe 11, which excludes the penetration of the produced product into the tubing string 1.

An additional elevator column of pipes 2 is lowered with a check valve 7 and a drain valve 22, an internal branch pipe 21, and connected to the connection with the parallel anchor unit 9.

The main tubing string 1 is filled with light, low-viscosity, degassed oil 8 (for example, Devonian oil), so that when the column of pump rods 6 moves in it, minimal hydraulic resistance to its movement is ensured and, accordingly, minimal amplitude of loads at the point of suspension of the rods.

The installation works as follows.

Well output enters the intake of the SSHN 3 through perforated pipe 15. A 180-degree flow reversal in the open section of the semi-casing 16 causes free gas bubbles to rise into the annular space. These bubbles are then discharged through the wellhead valve (not shown in the diagram) into the collection line. Some large solids are deposited in container 17.

During operation, wellbore fluid containing sand is lifted to the wellhead via tubing string 2, the internal diameter of which is selected to be minimal to maximize fluid flow rate and sand removal (e.g., 48 mm tubing or 60 mm tubing according to GOST 633-80). Lifting wellbore fluid through a separate channel, equipped with a check valve 7 at the bottom, minimizes sand ingress from above into the gap of the plunger pair of the SSHN 3.

The density of the light, low-viscosity oil in tubing string 7 should be lower than the well's production density. This, combined with the presence of collar 12, will prevent it from flowing from the bottom of tubing string 7 into tubing string 2, which is used to lift the production. The low-viscosity, degassed oil remains within tubing string 1, since tubing string 1 is closed at the wellhead.

During shutdowns, mechanical impurities (sand) settle in the gap between the inner pipe 21 and the inner surface of the lift pipe 2, which serves as a sand collector. Depending on the concentration of mechanical impurities, the number of check valves 7, inner pipes 21, and drain valves 22 can be increased, with them being evenly distributed along the length of the additional lift pipe string 2. Protective sleeve 10 prevents the small amount of mechanical particles remaining between the lower check valve and the SRP 3 from entering the SRP 3.

The equipment is lifted in the following manner.

An additional tubing string 2 is raised with a preliminary drop of a crowbar to activate the drain valve 22; if there are several check valves 7 and drain valves 22, the activation of the drain valve 22 by dropping the crowbar is repeated after the upper check valve 7 has been removed. In this case, the liquid from the tubing string is drained through the open hole of the drain valve 22, which prevents contamination of the area around the well.

Next, the rod string is extracted by disconnecting the automatic coupling 13, the main tubing string 1 is lifted, and the liquid is drained through the drain holes 14 in the cylinder of the SSHN 3, which are always closed by the plunger 5 during operation of the installation.

Installing a sucker rod pump with parallel tubing strings for wells with increased sand production prevents settling sand from entering the pump plunger pair gap, the plunger's internal cavity, and the discharge valve when the well is shut in. This also improves the reliability of the check valve and eliminates complications when retrieving downhole equipment. It also eliminates the penetration of well production into the main tubing string to prevent the rod string from hanging or the wellhead seal from becoming depressurized.

Claims (1)

A sucker rod pump installation with parallel tubing strings for operating wells with increased sand production, consisting of a downhole sucker rod pump (SRP) lowered on the main tubing string and capable of being driven through the sucker rod string, an additional tubing string with a check valve in the lower part, located parallel to the main tubing string, the main tubing string is filled with degassed low-viscosity oil, with a density lower than that of the well product, blocked at the top and communicated with the additional tubing string through a parallel anchor unit located directly above the SRP and equipped with a protective sleeve, characterized in that the main tubing string is equipped with a branch pipe with a reduced flow section and a polished inner surface, installed above the parallel anchor unit, a polyurethane cuff with cups facing the wellhead with the open part, is placed inside the branch pipe, wherein the cuff is installed on the sucker rod string and connected to the plunger of the SSHN through an automatic coupling, the cylinder of the SSHN is made with drain holes, below the cylinder of the SSHN a perforated branch pipe and a container made of tubing with a plug are installed in series, while the holes of the perforated branch pipe are covered with a cup-shaped half-casing, facing the open part to the wellhead, in the coupling connection between the pipes of the additional lifting column above the check valve a metal ring is installed, on which an internal branch pipe is fixedly fixed, plugged at the top, provided with slotted holes on the side surface in the upper part, above the internal branch pipe the additional lifting column is equipped with a drain valve.