RU2094592C1 - Valving device for flow regulation - Google Patents

Abstract

FIELD: oil production industry. SUBSTANCE: valving device has hollow body with through-passages, sealing collars on body, main and auxiliary isolating members rigidly connected by their upper ends with body, and by their lower ends they are connected with rod. Isolated chamber is formed between them. Also provided are lock, stem, and chamber above main isolating chamber which is filled with compressible working medium. Installed in body is additional isolating member which together with additional isolating member creates chamber which is filled with liquid. Stem can be made hollow and have radial passage under auxiliary isolating member. Isolated chamber between main and auxiliary isolating members can be filled with liquid. Additional lock can be installed in body rigidly connected with upper lock through additional stem. Both locks when found in extreme lower position can isolate space between locks and body from space which is created above and below locks. Diameters of locks are equal. With locks in extreme upper position, cross-sectional area of passages in body above lower lock is larger than axial cross-sectional bore area in body between locks and this bore area is larger than cross-sectional area of passages in body below upper lock. Cross-sectional area of passages in body under lower lock is less than minimal cross-sectional area of axial through-passage in body. EFFECT: higher efficiency and reliability in operation. 4 cl, 3 dwg

Description

 The invention relates to the oil and gas industry, in particular to the technique of oil production and can be used to automatically control the pressure of the fluid flow during the launch and operation of wells, and mainly when operating a well with periodic gas lift and high bottomhole pressure.

 A valve device [1] is known that includes a hollow body with passage channels, sealing cuffs on the body, a disconnecting element in the form of a bellows, rigidly connected with its upper end to the body, and the lower end to the shutter rod of the chamber above the disconnecting element, a charging unit for filling the latter working compressible medium.

 It is also known valve device [2] including a hollow body with passage channels, sealing cuffs on the body, the main and auxiliary uncoupling elements in the form of bellows, rigidly connected with their upper ends to the body, and the lower ends with a rod, between which insulated chambers are formed, the shutter rod rigidly connected with the rod, a camera above the main uncoupling element, a charging unit for filling the last working compressible medium.

This valve has the following disadvantages:
does not provide discrete opening and closing of the valve, which reduces the efficiency of its operation with periodic gas lift;
low reliability at high opening pressures due to a violation of the tightness of the charging unit, since a high charging pressure in the bellows chamber is required;
low bandwidth.

 The purpose of the invention is improving the efficiency and reliability of the valve device. The positive effect of the use of a valve device is expressed in an increase in oil production by maintaining the technological mode at a given level and increasing the service life of the valve device.

The specified goal is achieved due to the following technical solutions:
an additional disconnecting element (in the form of a bellows or a piston) is fixed in series in the housing, rigidly connected with its upper end to the housing, and the lower end with the rod and forming a chamber filled with liquid with the auxiliary disconnecting element;
the rod can be made hollow and have a radial channel under the auxiliary disconnecting element;
the insulated chamber between the main and auxiliary disconnecting elements may be filled with liquid;
an additional shutter can be sequentially installed in the housing, rigidly connected to the upper shutter via an additional rod, both shutters are installed with the possibility of disconnecting the cavity between the shutters and the housing from the cavity formed above and below the shutters in the lowest position, the diameters of the shutters are equal to each other; their upper extreme position, the cross-sectional area of the channels on the housing above the lower shutter is larger than the axial flow cross-sectional area of the housing between the gates, and the latter is larger than the channel in on the housing under the upper shutter, and the cross-sectional area of the channels on the housing under the lower shutter is less than the area of the minimum passage section of the axial channel of the housing (this provides a narrowing, i.e., throttling of the liquid in the longitudinal channels of the housing and controlling the operation of the valve device from the pressure of only one medium, for example, liquid or gas;
uncoupling elements can be made in the form of a piston.

 These features as a whole make it possible to increase the efficiency and reliability of the valve device by expanding the scope of its application, the discreteness of its regulation and increasing the service life.

 An additional uncoupling element is rigidly connected to the rod (option 1), and its chamber is hydraulically connected to the upper chamber filled with a working compressible medium. In this case, the resistance to opening the valve device increases in proportion to the ratio of the area of the disconnecting elements, which allows to reduce the pressure in the upper chamber at high values of the opening pressure.

 An additional disconnecting element is disconnected from the rod (option 2) and its chamber does not have hydraulic connection with the upper chamber. This increases the force acting on the additional uncoupling element, which can significantly reduce the charging pressure in the upper chamber at high opening pressures.

 If the chamber between the disconnecting elements is filled with an incompressible medium (liquid), then a discrete opening and closing of the device is ensured due to the static discontinuity of the liquid continuity (this allows you to expand the control range of the device for periodic gas lift).

 In Fig 1, 2 shows a General view of the valve device with uncoupling bellows in the closed state; in FIG. 3 also in the open position with uncoupling pistons.

 The valve device includes a hollow body 1 with passage channels (for example, in the form of longitudinal slots) 2 and / or 3, and channels 4, the main uncoupling element 5 (in the form of a bellows or piston), rigidly connected to the shaft 6 and installed in the upper part of the body 1, thus forming a sealed chamber 7 filled with a compressible medium. An auxiliary uncoupling element 8 (in the form of a bellows or a partition with a seal) is also installed in the housing 1, which forms a sealed closed chamber 9 with the housing 1 and the rod 6.

 If discrete control of valve opening and closing is required, then the chamber 9 is filled with a practically incompressible vapor-saturated liquid.

 If it is necessary to reduce the pressure in the chamber 7 at high opening pressures, then the chamber 9 is filled with a working compressible medium (for example, gas). To significantly reduce the pressure in the chamber 7, an additional disconnecting element 10 is installed in the housing in the form of a bellows or piston, forming a chamber 11 filled with liquid with the housing 1. In one case (Figs. 1 and 3), the chamber 11 is hydraulically connected to the chamber 7 through the radial channel 12 of the hollow rod 6, while the end of the latter is rigidly connected to the upper end of the rod 13, and hence with the uncoupling element 10 (chambers 7 and 11 are hydraulically reported). In another case (Fig. 2), the rod 6 is made without a radial channel 12 and its end face is not connected with the rod 13, i.e. the end face is disconnected from the uncoupling element 10 (chambers 7 and 11 are not hydraulically communicated).

 The uncoupling element 10 is rigidly connected to the rod 13, and the latter is rigidly connected to the shutter 14.

 If it is necessary to increase the cross-sectional area of the valve device, an additional shutter 15 is installed in series in the housing 1, which is rigidly connected to the upper shutter 14 through the rod 16. The diameters of the shutters 14 and 15 are made identical to balance their state from one medium. When the shutters 14 and 15 are in the upper position, the area of the open sections of the channels 2 is less than the section of the annular channel 17 formed between the housing 1 and the rod 16, and the open sections of the channels 3 located under the shutter 15 are smaller than the cross-sectional area of the axial channel 18 and less than the cross-sectional area of the channels 4 of the body 1. This provides a throttling flow of liquid or gas in the channels 2 and 3 in any open position of the valves 14, 15.

The equation of the balance of forces acting on the state of the device is as follows:
For FIG. one:
(P _o + dP _o ) • S _o (P-dP) • (S _o -S _c ) + (P _o + dP _o ) • (S _d + S _c ) + K _o • L _o + K _in • L _c + K _d • L _d <P _y • S,
if we take S _о S _д S> S _в , then
R _y > (P _o + dP _o ) • (2-S _in / S _d ) - (P-dP) • (1-S _in / S _d ) + (2K _d • L _d + K _in • L _c ) / S _d ;
For FIG. 2:
(P _о + dP _о ) • S _о (P-dP) • (S _о -S _в ) + K _о • L _о + K _в • L _в - (P _д + dP _д ) • S _в + (P _д + dP _d ) • S _d + K _d • L _d <P _y • S,
if we take S _о S _д S> S _в , then
P _y > (P _o + dP _o ) • (2-S _in / S _d ) + (P-dP) • (1-S _in / S _d ) + K _d • L _d / S _d + (K _o • L _о + K _в • L _в ) / S _д .

Where:
P _{about the} pressure in the chamber 7 when the device is closed;
dP _{about the} change in pressure in the chamber 7 when the device is open;
P the pressure in the chamber 9 when the device is closed;
dP pressure change in the chamber 9 when the device is open;
P _{d the} pressure in the chamber 11 when the device is closed (Fig. 2);
dP _{d is the} change in pressure in the chamber 11 when the device is open (for Fig. 2);
P _{y the} pressure control device from the flow of liquid, gas-liquid mixture and / or gas;
S _o , S _in , S _{d the} transverse area of the main 5, auxiliary 8 and additional 10 uncoupling element under pressure;
S is the transverse area of the additional uncoupling element 10 and (or) the gates 14 and 15, under the influence of the pressure of the fluid flow, gas-liquid mixture and / or gas;
K _about , K _in , K _{d the} coefficient characterizing the stiffness of the main 5, auxiliary 8 and additional 10 disconnecting element in the form of a bellows (Fig. 1, 2);
L _about , L _in , L _{d the} course of the main 5, auxiliary 8 and additional 10 disconnecting element;
The valve device operates as follows.

The device is calibrated at a predetermined pressure before being launched into the well. For this, the chamber 7 is filled (for example, through the charging unit) with a compressible medium at the design pressure. In this case, forces arise from the influence of pressure (Fig. 1, 3) of the compressible medium on the transverse area of the main uncoupling element 5 (F _о ) and on the difference between the areas of the additional 10 and auxiliary 8 uncoupling elements (F _g ). Then the total force FF _о + F _g will act on the closing side of the shutter 14 (or shutters 14 and 15) through the rod 13.

According to FIG. 2, when the chamber 7 is charged with a compressible medium, the pressure in the chamber 11 will also increase, since the liquid in the chamber 11 is practically incompressible. In this case, the force F _о will be equal to the pressure in the chamber 7 multiplied by the difference in the areas of the main 5 and auxiliary 8 disconnecting elements, and the force F _g . will be equal to the pressure in the chamber 11 multiplied by the area of the additional uncoupling element 10. When the total counter-directional force F _p (arising from the pressure of the liquid or gas flow acting on the area of the shutter 14 or the shutters 14, 15 and the additional uncoupling element 10) is greater than force F, then the shutter 14 (shutters 14 and 15) moves up and the device opens.

In the case of discrete control, the shutter 14 (or shutters 14 and 15), under flow pressure, exerts pressure on the uncoupling element 5 through the rod 6. In this case, the liquid in the chamber 9 exerts resistance and the rod 6 does not noticeably move, but when the control force exceeds critical strength
F _y > F _cr. (PP _us. ) • (S _о S _в ),
then the uncoupling element 5 begins to (instantly) move, and between the uncoupling elements 5 and 8 above the liquid in the chamber 9 a cavity 19 is formed (Fig. 3), filled with steam with a saturation pressure P _us. (Krivchenko GI Hydraulic machines: Turbines and pumps. Textbooks for high schools. M. Energy, 1978. S. 102-105, 320).

 If it is necessary to reduce the pressure of the compressible medium in the chamber 7 - ensure the effect of this pressure on the area of the uncoupling element 5, while the chamber 9 is filled with a compressible medium (for example, gas) with a lower pressure (for example, atmospheric). The pressure in the flow acts on the valve 14 (or valves 14, 15), having a diameter less than the uncoupling element 5. This allows you to open the device at low pressure in the chamber 7 and high pressures in the fluid flow, thereby expanding the scope of the device at high pressures in the stream or at the bottom of the well.

 Opening the device from high pressure medium flow at low pressure in the chamber 7 can also be achieved by increasing the diameter of the shutter 14 (or shutters 14, 15) more than the diameter of the uncoupling element 5. In this case, the resistance to opening the device from the fluid flow increases due to the effect gas pressure (controlled by a pressure regulator from the well surface) to the difference between the areas of the shutter 15 and the uncoupling element 5 (the shutter 14 and channels 2 are excluded from the device).

 To significantly reduce the charging pressure, the pressure of the compressible medium in the chamber 7 is provided on one or more additional disconnecting elements (for example, on element 10). This can also be achieved by freely placing the auxiliary uncoupling element 8 (for example, having a diameter smaller than the main uncoupling element 5) in a sealed insulated chamber 11 (Fig. 2).

 When opening the device, gas passing through the channels 3, 2 and 4 of the housing 1, enters the lift. When the pressure in the stream drops below the opening pressure, the valves 14 and 15, moving downward, block the flow of medium into the lift. Thus, the device opens and closes depending on the selected technical and technological characteristics of the valve, based on the optimal operating conditions of the well.

Claims (5)

 1. Valve device for regulating the flow, including a hollow body with passage channels, sealing cuffs on the body, the main and auxiliary uncoupling elements, rigidly connected with their upper ends with the body, and lower ends with the shaft with the possibility of formation of an insulated chamber between them, the main rod with a shutter and a chamber above the main uncoupling element, filled with a working compressible medium, characterized in that it is equipped with an additional uncoupling element made in the form of a bellows or shnya mounted in the housing to form a series with an auxiliary uncoupling element chamber filled with liquid.  2. The device according to claim 1, characterized in that the rod is hollow and has a radial channel located above the auxiliary uncoupling element for communicating with the camera above the main uncoupling element with the camera between the auxiliary and additional uncoupling elements.  3. The device according to claim 1, characterized in that the insulated chamber between the main and auxiliary disconnecting elements is filled with liquid.  4. The device according to claim 1, characterized in that it is equipped with additional stem and shutter sequentially located in the housing, the additional shutter being rigidly connected to the main additional rod, the diameters of the shutters are equal to each other, both shutters are installed with the possibility of separation of the cavity between the shutters and the housing from the cavity above and below the gates at its lowermost position, and at the extreme upper position of the gates, the axial throughput section of the housing between the gates is smaller than the passage cross-sectional area analyte in the housing above the bottom shutter, but greater than the area of the cross sections of flow channels under the top gate, and the cross sections of flow channels under the lower gate area smaller than the area of the axial housing opening area under the lower shutter.  5. The device according to claim 1, characterized in that the main and auxiliary uncoupling elements are made in the form of pistons.

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