RU2353808C1 - Plant for dual operation of two beds - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention is related to oil industry and may find application in oil production from two beds of single well. The plant includes sucker-rod pump with plunger, cylinder, suction and pressure valves. Cylinder is equipped with side valve with filter. Auxiliary cylinder with side holes is fixed in cylinder, as well as jacket with provision of annular space between auxiliary cylinder and annular space jacket. Lower end of cylinder is plugged with plug. Suction valve, filter and tail with packer at the end are fixed on jacket. Plunger is arranged as combined, consisting of upper and lower plungers connected with stem with valves, with installation of upper plunger inside cylinder and lower plunger inside auxiliary cylinder. Lower plunger and stem have channel for communication of space above and under lower plunger. Upper plunger and stem have channel for space connection under upper plunger with inlet to upper plunger valve.

EFFECT: provision of serviceability at any values of pressure in operated beds and possibility to operate only one of beds.

3 dwg

Description

The invention relates to the oil industry and may find application in oil production from two layers of the same well.

Known pumping unit for the separate operation of several layers, which includes a column of elevator pipes, sucker rod pump, packer and liner. The sucker rod pump is equipped with an additional suction valve located on the side wall of the cylinder, which divides the cylinder in length into two parts, proportional to the productivity of the layers. The installation provides the possibility of entering the pump cylinder when the plunger moves upward first to produce low-pressure formation, and after the plunger passes an additional valve, to produce high-pressure formation (RF Patent No. 2221136, published. 2004.01.10).

A disadvantage of the known installation is the difficulty of separating the cylinder depending on the productivity of the layers and the practical inoperability in the conditions of the changing flow rate of at least one of the layers, which in practice often takes place.

Closest to the proposed invention in technical essence is a borehole sucker-rod pump installation comprising a sucker-rod pump with a plunger, a cylinder, suction and discharge valves, a pipe located concentrically to the pump cylinder and forming a sealed chamber with holes in the upper part for liquid to enter the plunger pump area, with a flow distributor with an additional valve and feedthroughs (RF patent No. 2293215, published. 2007.02.10 - prototype).

The installation allows the selection of fluid from two layers with different pressures. However, the installation has the following disadvantages:

- the dependence of the installation on the pressure difference of the reservoirs. With small values of the pressure differences of the exploited formations, the operation of the installation becomes impossible;

- mismatch between the actual selected production rates of each formation calculated, therefore, it is difficult to assign the optimal production rates of each formation according to the modes of field development;

- preliminary studies are required to determine the water cut of each formation. There is no direct definition of water cut;

the inability to exploit in wells complicated by asphalt-resinous paraffin deposits (paraffin deposits);

- has a restriction on the viscosity of the selected fluid (up to 0.025 Pa · s);

the dependence of the pump design itself on the bottomhole pressures of the reservoirs being operated (depending on the magnitude of the pressure, one or another pump design is used);

- there is no possibility of operating only one of the layers, completely isolating the other.

The proposed invention solves the problem of ensuring operability at any pressure values of the exploited reservoirs, ensuring pump performance in accordance with the flow rates of the reservoirs, providing the possibility of operating only one of the reservoirs, completely isolating the other.

The problem is solved in that in the installation for simultaneous and separate operation of two layers, including a sucker rod pump with a plunger, a cylinder, a suction and discharge valves, according to the invention, the cylinder is equipped with a side valve with a filter, an auxiliary cylinder with side holes and a casing are fixed on the cylinder with the formation between auxiliary cylinder and casing of the annular space, the lower end of the cylinder is sealed with a plug, a suction valve, a filter and a shank with a packer at the end are fixed to the casing, not combined, consisting of a rod connected to the upper and lower plunger with valves, with the placement of the upper plunger inside the cylinder and the lower plunger inside the auxiliary cylinder, the lower plunger and rod have a channel for communicating the space above and below the lower plunger, the upper plunger and rod have a channel for connection spaces under the upper plunger with an entrance to the valve of the upper plunger.

SUMMARY OF THE INVENTION

Installation for simultaneous-separate operation of two layers is presented in figures 1, 2 and 3.

The installation consists of a cylinder 1, equipped with a side valve 2 with a filter 3, on which an auxiliary cylinder 5 is fixed with an adapter 4 and, through a sleeve 6, a casing 7 with the formation of an annular space 8 between the auxiliary cylinder 5 and the casing 7. The auxiliary cylinder 5 has side openings 9 The lower end of the auxiliary cylinder 5 is plugged with a plug 10. A suction valve 12, a filter 13, and a shank 15 are secured to the casing 7 using an adapter 11. A packer 16 is fixed to the end of the shank 15, which separates the upper plate Ast I from the lower layer II. Inside the cylinder 1, an upper plunger 17 is provided, equipped with a discharge valve 18, and inside the auxiliary cylinder 5, a lower plunger 19 is located, having a channel 20. The plungers 17 and 19 are rigidly fixed to each other by the rod 21, forming a combined plunger, which is driven by sucker rods 22 connected to a rocking machine (not shown). The rod 21 has holes on both sides for the passage of formation fluid 23 and 24, respectively. The installation was lowered into the production casing of the well 25 on the string of tubing 26 and connected to the last coupling 27.

Installation works as follows.

The installation is placed in the well 25 on the tubing string 26 so that the packer 16 provides complete isolation of the two operating formations I and II.

In the position where the passage of the side valve 2 is closed by the body of the plunger 17, the formation I is blocked. When the rod string 22 and the associated plunger 17 and the plunger 19 move upward, the valve 12 opens, the valve 18 closes. The formation fluid from the formation II passes through the liner 15 through the filter 13, valve 12, through the annular space 8, through the side openings 9, fills the space under the plunger 17, passes the hole 23, the channel 20 and enters the space under the plunger 19. A plug 10 in the auxiliary cylinder 5 is necessary to isolate the space beneath the plunger 19 from the liquid in the annular space 8. Until the lateral holes 9 are reached and blocked by the plunger 19, formation fluid is withdrawn only from formation II. When reaching and blocking the plunger 19 lateral holes 9, the fluid from the reservoir II ceases to flow into the device. The passage of the side valve 2, previously closed by the plunger 17, opens. The formation fluid from the reservoir I, having been cleaned in the filter 3 and opening the valve 2, enters the space under the plunger 17 and through the hole 23 and the channel 20 into the space under the plunger 19. Thus, the selection of fluid from the reservoir I occurs until the upper stroke limit of the combined plunger is reached.

When the combined plunger moves downward, valves 2 and 12 close and valve 18 opens. The fluid accumulated in the spaces under the plunger 17 and 19, through the channel 20, the openings 23 and 24 are displaced into the cavity of the tubing 26. Next, the cycle repeats.

Thus, in one cycle, the selection of fluid occurs first from formation II in isolation from formation I, then from formation I in isolation from formation II. The selection takes place in the complete isolation of the two layers from each other, ensuring independence of the selection of fluid, regardless of the pressure of the layers I and II.

The installation can also work in two other modes (see figure 2, 3).

When the reciprocating movement of the combined plunger in the interval a-b (figure 2), only the lower layer II works. The passage of the side valve 2 is closed by the body of the plunger 17, providing overlapping of the formation I. When the combined plunger moves upward from a to b, the formation fluid is sucked through the valve 12, passing through the annular space 8 and the side openings 9, and fills the space under the plungers 17 and 19. With during the combined plunger down from position b to position a, the reservoir fluid accumulated in the installation cavities is pumped through valve 18 into the tubing 26.

When the reciprocating movement of the combined plunger in the interval vg (Fig. 3), the side valve 2 is open, and the side holes 9 on the auxiliary cylinder 5 are closed by the plunger 19. As a result, the production of the well takes place only through the side valve 2 from formation I. From formation II, the selection of products does not occur.

The ability of the installation to work in these modes allows each individual reservoir to be studied separately (to determine flow rate, water cut, oil recovery, etc.), as well as organize periodic pumping of reservoir fluid from each formation with different parameters and with different cycles, without stopping the entire installation, adjusting the stroke length of the polished rod of the rocking machine (not shown) and the number of swings.

The intervals a-b and c-d depend on the lengths of the plungers used:

Where

L _a-b - the length of the interval a-b,

L _PL17 - the length of the plunger 17,

L _VG - the length of the interval VG,

L _PL19 - the length of the plunger 19.

Thus, the total stroke length of the combined installation plunger will be equal to:

or

where L _mouth - the total stroke length of the combined plunger.

This dependence allows you to adjust the amount of pumped reservoir fluid from each formation, changing only the lengths of the plungers 17 and 19 with the condition that the total length of the combined plunger does not change.

Using the proposed installation will allow the selection of well production from each formation optimally, which will give a significant increase in oil.

Application of the proposed installation will allow:

- to conduct a study of each formation according to flow rate and water cut without involving crews for routine well repair, adjusting the stroke length and the number of swings of the pumping unit;

- exploit one of the reservoirs, stopping the operation of another reservoir, regardless of their reservoir pressures. Thus, it becomes possible to exploit each formation periodically, changing the operating modes of the installation without involving teams for fluid well repair;

- operate in wells complicated by paraffin deposits;

- operate in wells with products with high viscosity;

- change the pumping parameters without lifting the entire installation to the surface.

Claims (1)

Installation for simultaneous and separate operation of two layers, including a sucker rod pump with a plunger, a cylinder, a suction and discharge valves, characterized in that the cylinder is equipped with a side valve with a filter, an auxiliary cylinder with side holes and a casing are fixed on the cylinder with the formation between the auxiliary cylinder and the casing annular space, the lower end of the cylinder is plugged with a plug, a suction valve is fixed to the casing, a filter and a shank with a packer at the end, the plunger is combined, consisting of the upper and lower plungers connected with the rod to the valves, with the upper plunger inside the cylinder and the lower plunger inside the auxiliary cylinder, the lower plunger and rod have a channel for communicating space above and below the lower plunger, the upper plunger and rod have a channel for connecting the space under the upper a plunger with an inlet to the valve of the upper plunger.

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