RU163755U1 - Borehole plug-in sucker rod pump - Google Patents

Abstract

1. A downhole sucker-rod pump containing a cylinder, two plungers located in it, a suction valve, a discharge valve installed in the first plunger, upper and lower stroke limiters of the first plunger, a cylinder stroke limiter made in its lower part, a rod string, this first plunger is movable and kinematically connected to the column of pump rods by means of a rod, the cylinder is made with the possibility of reciprocating motion, characterized in that the second plunger is made stationary th, the suction valve is arranged in the upper portion thereof, an upper plunger stroke limiter is configured with the function of the pusher cylinder and fixed to the rod string outside tsilindra.2. A pump according to claim 1, characterized in that the cylinder is made of at least two parts interconnected. A pump according to claim 1 or 2, characterized in that the discharge valve is forcibly opened. The pump according to claim 3, characterized in that it comprises a stroke limiter of the discharge valve, rigidly fixed to the rod of the movable plunger and made with the function of a pusher of the movable plunger.

Description

IPC F04B 47/02

Borehole plug-in sucker rod pump

The claimed technical solution relates to the field of oil production from reservoirs by sucker rod pumps and can be used in other areas of industry in the operation of wells.

Existing single-acting sucker-rod pumps are pumps with one working plunger-cylinder pair, namely pumps with a movable plunger or with a movable cylinder.

Well-known sucker rod pumps for oil production with a movable cylinder and one plunger (for example, RF patents No. 2561935, 1588910), with a fixed cylinder and two plungers (for example, RF patents No. 2160853, 2382902), as well as well pumps, which are simultaneously used a movable cylinder and several plungers (RF patents No. 2353806, 2201531, 2313696, No. 20940).

PUMP PUMP UNIT according to RF patent No. 2353806 (IPC F04B47 / 00) includes a pump cylinder with holes in the upper part that is muffled in the lower end part and installed in the housing with the possibility of reciprocating movement of the plunger with valves. The cylinder plugged in the lower end portion is movable with an annular groove and an abutment and is placed with the possibility of reciprocating movement inside the sub having side openings and sealing cylinders. The sub is screwed onto a cylinder connected to the tubing string and screwed through a sleeve into a casing, which in turn is screwed into a valve body equipped with a ball and a sludge trap. A plunger with a valve is connected on one side to the rod string and, on the other hand, to an auxiliary plunger having a side opening and a valve. The plunger forms a working pair with a cylinder, and the auxiliary plunger forms a working pair with a movable cylinder.

The disadvantage of this installation is the possibility of its use only when processing the bottom-hole zone of an oil well, but not for oil production. During oil production, gas is blocking oil in the near-wellbore zone of the wells, since the pressure at the pump intake is much lower than the gas saturation pressure of oil.

Borehole PUMP PUMP according to the patent of the Russian Federation No. 2313696 (IPC F04B47 / 00) contains an upper plunger, an upper cylinder, a rod string connected to a discharge valve, a lower cylinder, a pusher and a suction valve. The upper cylinder is stationary. The discharge valve is connected via a pusher to the lower plugged plunger. The lower cylinder is movable by the stroke amount of the suction valve, the annular locking member of which is mounted on the upper end of the lower cylinder. An annular seat is located at the lower end of the upper cylinder. The stroke of the suction valve is limited by the stop. The design of the pump increases the efficiency of its operation due to the application of the difference between the pressure in the tubing and in the well to the lower plunger during the down stroke, a significant passage section of the suction valve and the application of the friction force of the pair of lower plunger - lower cylinder to the latter during the up and down stroke, contributing, respectively, to the opening and closing of the suction valve.

The disadvantage of this device is the excessive complexity of the design of the pump with a significant reduction in the working volume of the cylinder, which leads to lower productivity and lower reliability of the pump.

According to the patents of the Russian Federation No. 20940 (IPC F04B47 / 02) and No. 2201531 (IPC F04B47 / 00), a Borehole PUMP PUMP WITH CONTROLLED VALVES contains a cylinder, plungers, a suction valve, a column of pump rods. The pump cylinder is movable relative to the tubing string and is equipped with a controllable discharge valve and a cross-shaped travel stop connected to the string of pump rods. The plungers are located in the cylinder and are movable and stationary. The fixed plunger is connected to the hollow stem with the lower end and the suction valve with the upper end. The movable plunger has a lower end connected to the seat of the suction valve, the upper end is in contact with the cross-shaped stroke limiter of the movable plunger by the amount of stroke of the suction valve. A cross-shaped travel limiter of the movable plunger is connected by a rod to the suction valve. The reliability of the pump and the filling factor of the pump are increased by eliminating failures when closing the suction and discharge valves by forcing them from the reciprocating movement of the rod string. The device allows to increase the reliability of the downhole sucker rod pump and the filling factor of the pump by eliminating failures when closing and opening the suction and discharge valves by forcing them from the reciprocating movement of the rod string.

The disadvantage of this pump is the reduction in the volume of the working cavity of the cylinder due to the plunger - an element that controls the insert valve, occupying a significant place in the cylinder, and, as a result, reduced productivity.

The closest analogue is the WELL PUMP UNIT according to the invention SU 850915 (IPC F04B 47/02), comprising columns of pump pipes and rods, a fixed cylinder located in the castle support, equipped with a suction valve, a movable cylinder and a plunger located therein with a discharge valve. The plunger is connected to the rod string. Between the fixed and movable cylinders, a tubular element is installed, at the ends of which additional plungers are located. Additional plungers interact with the inner surfaces of the fixed and movable cylinders. The fixed cylinder is at the top and the movable cylinder at the bottom is provided with collars. The movable cylinder has stroke limiters for the main plunger.

Existing single-acting sucker-rod pumps are single-plunger-cylinder pumps — whether they are pumps with a moving plunger or pumps with a moving cylinder. The authors are not aware of pumps with one cylinder, in which two plungers with valves would be placed, forming two working hydraulic pairs, capable of working in series to create a working cavity of the cylinder and fill it with liquid and supply it to the surface.

An exception is the pumping unit according to the copyright certificate SU No. 850915, adopted as a prototype, which has two hydraulic pairs in series. The first pair is a plunger, consisting of a movable plunger and a fixed upper part of the movable cylinder. The second pair is a telescopic one, consisting of the movable part of the telescopic pump (the movable part of the movable cylinder, the central pipe with additional plungers) and the stationary cylinder - the body of the telescopic pump. In dynamics, this design represents the work of two pairs working in series.

The disadvantage of this installation is the high metal consumption, design complexity and unreliability due to the introduction of additional plungers, a tubular element. A significant distance between the discharge and suction valves leads to a decrease in the fill factor of the pump cylinder and increases the likelihood of blocking the pump with gas, which ultimately reduces the efficiency of the installation.

The objective of the proposed technical solution is to create a pump that ensures the sequential operation of two plungers in one cylinder in one working stroke.

The technical result is to increase the productivity of the pump.

The technical result of the claimed utility model is achieved by the fact that the borehole plug-in sucker rod pump comprises a cylinder, two plungers located in it, a suction valve, a discharge valve installed in the first plunger, upper and lower stroke limiters of the first plunger, a cylinder limiter made in its lower part , a string of pump rods, wherein the first plunger is movable and kinematically connected to the string of pump rods, the first plunger is connected to the string of pump rods by means of a rod, the cylinder made with the possibility of reciprocating movement, according to the claimed solution, the second plunger is fixed and equipped with a suction valve in its upper part, the upper limiter of the plunger travel is made with the function of a cylinder pusher and is mounted on the column of pump rods outside the cylinder.

The cylinder may be made of at least two parts interconnected.

The discharge valve can be made forcibly opening, while the pump contains a stroke limiter of the discharge valve, rigidly fixed to the rod of the movable plunger and made with the function of a pusher of the movable plunger.

The proposed device is illustrated by drawings of FIG. 1-3:

in FIG. 1 is a schematic drawing of a device: (a) in the lower position of the movable plunger and cylinder, (b) in the upper position of the movable plunger and cylinder;

in FIG. 2 is a schematic drawing of a device with a forced-opening discharge valve: (a) in the lower position of the movable plunger and cylinder, (b) in the upper position of the movable plunger and cylinder;

in FIG. 3 is a schematic drawing of a device with a cylinder consisting of two parts interconnected by a fastener, for example, in the form of a sleeve: (a) in the lower position of the movable plunger and cylinder, (b) in the upper position of the movable plunger and cylinder;

where positions 1-15 are indicated:

Rod string;

The upper stroke limiter of the movable plunger 7, which performs the function of a pusher cylinder 6;

Guide rod;

Lower limiter of the stroke of the movable plunger 7;

The stem of the movable plunger 7;

Cylinder;

Movable plunger;

Discharge valve;

Suction valve;

Fixed plunger;

The hollow stem of the stationary plunger 10;

The limiter of the stroke of the cylinder 6;

Anchor spindle for locking support;

Tubing string;

The stroke limiter of the discharge valve 8, which performs the function of a pusher of the movable plunger 7.

The downhole plug-in sucker-rod pump comprises a cylinder 6 with a stationary plunger 10 located therein with a ball suction valve 9, a movable plunger 7 with a pressure valve 8, a column of pump rods 1 kinematically connected to the rod 5 of the movable plunger 7. In this case, the movable plunger 7 is rigidly fixed to rod 5. On the rod-rod sub, an upper stroke limiter 2 of the movable plunger 7 is installed. An upper stroke limiter 2 of the movable plunger 7 is mounted on the pump rod string 1. Upper stroke limiter 2 of the movable plunger Gers 7 is made with the possibility of abutment in the guide 3 of the rod 5. Due to this embodiment, the stroke limiter 2 of the movable plunger 7 also has the function of a cylinder pusher 6. The upper limiter 2 of the stroke of the movable plunger 7 is made outside the cylinder. The fixed plunger 10 is rigidly connected through the hollow rod 11 to the anchor spindle 13 under the locking support located in the tubing string 14. In the upper part of the cylinder 6, a lower travel stop 4 of the movable plunger 7 and a guide 3 of the rod 5 of the movable plunger are installed 7. In the lower part of the cylinder, on its inner surface, a stroke limiter 12 of cylinder 6 is installed. The discharge valve 8 is located in the lower part of the movable plunger 7. The suction valve 9 is fixed in the upper part th plunger 10.

In the claimed device, the discharge valve 8 in the movable plunger 7 can be made forcibly opening. Forced opening pressure valve 8, in contrast to conventional ball valves, opens and closes regardless of the pressure drop - with the help of mechanical movement: up - closed, down - open. The forced opening of the discharge valve 8 consists of a seat mounted in the lower part of the movable plunger 7, a locking element and a rod. The rod of the discharge valve 8 is located in the inner cavity of the movable plunger 7. The rod of the discharge valve 8 in the lower part is rigidly connected to the locking element, in the upper part through the limiter 15 of the discharge valve 8 is connected to the rod 5 of the movable plunger 7. The limiter 15 of the stroke of the discharge valve 8 performs also the function of the pusher of the movable plunger 7 during operation of the discharge valve 8 to open (downward movement). In this case, the discharge valve 8 is kinematically connected through its rod to the rod 5 (movable plunger 7), which in turn is kinematically connected to the column of pump rods 1.

Forced opening of the discharge valve eliminates the delay in opening it when the plunger moves down, which eliminates the blocking of the pump by gas under conditions of high gas content in the oil mixture, which leads to an increase in the productivity of the pump unit as a whole.

Cylinder 6 may be made of at least two parts interconnected. The connection of the parts of the cylinder 6 can be carried out, for example, by means of a coupling or by any known means of connecting two metal parts, which simultaneously performs the function of the limiter of the stroke of the movable plunger 7. The execution of the cylinder consisting of two parts also helps to increase the productivity of the pump installation by reducing leakage between the plunger and the cylinder due to the best ability to achieve straightness, eccentricity of each of the cylinders separately. At the same time, an increase in the service life of the product, a decrease in the accuracy requirements for metalworking machines for cylinder production, and, as a result, a reduction in the cost of the product are achieved. And also there is the possibility of creating a long-stroke pump, the length of which is equal to the sum of the lengths of the connected cylinders.

Downhole insert rod pump operates as follows.

When the column of pump rods 1 moves upward, the movable plunger 7 also moves up to the limiter of its stroke 4 and, abutting against it and continuing to move upward, transmits the movement upward to the cylinder 6, which, rising upward, ends its movement at the contact point of the stroke limiter 12 of the cylinder 6 with a fixed plunger 10. During the upward stroke, the discharge valve 8 is closed and the suction valve 9 is open, i.e. there is a process of suction of the liquid into the working cavity of the cylinder, and the fluid cut off by the discharge valve 8 from the cavity above the cylinder 6 is supplied to the tubing string 14.

At the beginning of the movement of the string of pump rods 1 upward relative to the tubing 14, the cylinder 6 is simultaneously stationary for the movable plunger 7 and movable for the stationary plunger 10 - thus, two working pairs are formed in one cylinder: “movable plunger - stationary cylinder” and “ fixed plunger - movable cylinder ”, working sequentially in one working stroke. When the movable plunger 7 rests on its stroke limiter 4, the movement of this plunger stops relative to the cylinder 6, then the cylinder 6 begins to move relative to the stationary plunger 10. That is, the second working pair “stationary plunger - movable cylinder” begins to work.

When the column of pump rods moves down, two pairs also work sequentially - “movable cylinder - fixed plunger” and “movable plunger - fixed cylinder”. When the rod string 1 moves downward, the movable plunger 7 moves downward until the travel stop 2 rests against the guide 3 of the rod 5. At this moment, the travel stop 2 starts to act as a cylinder pusher 6 and transfers downward movement to the cylinder 6. At the same time, the suction valve 9 of the fixed plunger 10 closes and the discharge valve 8 of the movable plunger 7 opens, i.e. there is a process of fluid injection, which consists in transferring it to the plunger surface of the movable plunger 7 and then to the tubing 14. Thus, the discharge valve 8 begins to open due to a change in pressure difference, namely, when the pressure in the interplunger space exceeds the pressure in space above the movable plunger 7. Cylinder 6, abutting the limiter 12 of its stroke against the anchor spindle 13 under the lock support, stops its movement and starts moving the movable plunger 7 with respect to of the cylinder 6. That is, the working pair “movable plunger - stationary cylinder” works.

When the cylinder is made of at least two parts interconnected, the operation of the claimed device in this case is carried out in the same manner as described above.

If the discharge valve 8 is made forcibly opening, in this case, the operation of the device will change when the bar starts to move down. Namely: when the rod moves down the valve is forced to open, then the limiter 15 of the stroke of the discharge valve 8 rests against the movable plunger and gives it a downward movement, then the operation is performed as described above; when the rod moves up, the discharge valve 8 is forcibly closed, and due to the rigid connection of the discharge valve 8 with the rod 5 and the discharge valve 8 is forced to open, the movable plunger 7 starts its upward movement, and then the device operates as described above.

The use of a forced-opening pressure valve in well pumps eliminates the delay in opening the pressure valve when the plunger moves down and the harmful effect of gas when working with an oil and gas mixture, thereby increasing the performance of the pump in an environment with a high gas content, reducing the likelihood of gas blocking the pump.

Thus, it was possible to increase the working cavity of the cylinder without changing the overall dimensions of the cylinder itself due to the possibility of sequential movement of two working pairs “movable cylinder - fixed plunger” and “movable plunger - fixed cylinder” in one working stroke, increasing the performance of the pump. The work of two working pairs in one cylinder became possible due to the placement of two plungers in one cylinder - movable and stationary, in the first of which the discharge valve 8 is made, in the second - the suction valve 9, and also due to the presence and location of the 2, 4 stroke stops movable plunger 7 and stroke limiter 12 of cylinder 6.

The minimum distance between two valves - suction 9 and discharge 8 - is achieved at the moment when both the movable plunger 7 and the cylinder 6 are in their lower position. Reducing this distance allows you to pump almost all the pumped oil from the interplunger space into the supraplunger space - the space above the movable plunger 7.

As one example of the implementation of the inventive sucker rod pump contains a cylinder with a diameter of 44.5 mm, a length of 7 m, two plungers located in it with the following parameters: plunger stroke length - 6 m, plunger length - 1.2 m. Two plungers are located in the cylinder : mobile and motionless. The cylinder is equipped with a stroke limiter made in the form of a step on the inner wall in the lower part of the cylinder. The movable plunger is kinematically connected to the column of pump rods by means of a rod and is equipped with upper and lower stroke limiters - in this case, an adapter between the rod of the movable plunger and the rod acts as an upper limiter. The upper limiter of the stroke of the plunger is made with the function of a cylinder pusher and is mounted on the column of sucker rods outside the cylinder. As a lower limiter is a ledge on the inner wall of the cylinder in its upper part. A discharge valve is located in the movable plunger, and a suction valve is located in its upper part in a fixed plunger. In this case, the discharge and suction valves of the pump are made in the form of a ball-seat.

When performing a pump with a cylinder consisting of two parts interconnected by a coupling, the length of each cylinder is 3.5 m. The execution of the cylinder, plungers and valves is similar to that indicated in the above example.

When performing a pump with a force-opening valve, the parameters of the cylinder and plungers are similar to those described in the above example. In this case, the pump contains a stroke limiter of the discharge valve, which is rigidly fixed to the rod of the movable plunger and is configured as a pusher of the movable plunger. The clutch acts as a travel limiter.

Claims (4)

1. A downhole sucker-rod pump containing a cylinder, two plungers located in it, a suction valve, a discharge valve installed in the first plunger, upper and lower stroke limiters of the first plunger, a cylinder stroke limiter made in its lower part, a rod string, this first plunger is movable and kinematically connected to the column of pump rods by means of a rod, the cylinder is made with the possibility of reciprocating motion, characterized in that the second plunger is made stationary th, the suction valve is arranged in the upper portion thereof, an upper plunger stroke limiter is configured with the function of the pusher cylinder and fixed to the rod string for the outside of the cylinder. 2. A pump according to claim 1, characterized in that the cylinder is made of at least two parts interconnected. 3. The pump according to claim 1 or 2, characterized in that the discharge valve is made forcibly opening. 4. The pump according to p. 3, characterized in that it contains a stroke limiter of the discharge valve, rigidly fixed to the rod of the movable plunger and made with the function of the pusher of the movable plunger.

Images