RU2483196C1 - Process circulating valve - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: valve consists of a body with a through axial channel, and upper branch pipe and a lower connecting thread. The housing is equipped with an internal annular bore and seats with sealing rings rigidly installed in its radial holes. A gate valve is made in the form of two poppet valves, each of which is equipped with a guide entering an axial channel of the set in a movable manner. At that, a ring spring with threaded holes is freely installed in an annular groove. Poppet valves are equipped with a mating thread and rigidly attached to the ring spring.

EFFECT: possibility of development of wells by creating a hydrodynamic connection of inter-tube space with an axial channel of a production tubing string through a circulating valve.

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Description

The invention relates to the oil and gas industry and is intended to communicate annular space with the cavity of the lifting pipes when killing and developing wells.

A known circulation valve (see I AS No. 443161, EV 33/14), comprising a housing with radial channels, a seat, a spring-loaded differential sleeve with collars on the outer surface, a seal, locking elements, which allows you to create circulation between the annulus and lift pipe string.

The disadvantages of the valve include low reliability in operation, not ensuring the circulation of the liquid at given pressure drops.

A known circulation valve (see II A.S. No. 968336), comprising a housing with a radial hole, a nut and a membrane installed in the radial hole of the housing between two rings having different inner diameters.

The valve is installed in the tubing string and is lowered into the well to a predetermined depth. The valve can be opened both internally and externally by creating excess pressure and rupturing the membrane. The pressure required to rupture the membrane from the side of the annulus is much less than the pressure created in the tube space. The valve is adjusted to the set pressure by changing the inner diameter of the rings.

However, in some cases, after rupture of the membrane, for example, in the case of washing the sand plug in the tubing string, it is necessary to continue the operation of the well, but this is not possible due to the need to raise the pipes to the surface to replace the membrane.

It is also necessary to take into account the operating conditions of the well, for example, during sucker rod pumping, the hydrostatic pressure in the pipe tubing can significantly exceed the similar pressure in the annulus, which in turn can lead to premature operation of the device.

Known downhole valve device (III see US Pat. RF No. 20111796, Mcl E21B 34/06), taken by the authors as a prototype and consisting of a pipe with a passage channel and a radial hole, with a hollow body housed in it with holes for fluid passage, spring-loaded a shutter with a locking protrusion and a sealing surface for interacting with the seat, a spring-loaded shaft and a sleeve, a fixing unit in the form of rods, with a locking groove on the inner surface of the housing.

The rods are installed in the shutter with the possibility of interaction with the protrusion of the shaft and the sleeve, in the extreme right position of the shutter and placed in the fixing groove of the housing in its extreme left position.

The disadvantage of this device is the small cross-section for the passage of flushing fluid, which reduces the efficiency of the work associated with flushing the sand plug, where it is necessary to have a high flow rate.

The presence of the valve shutter fixing assembly in the open position and the structure itself, i.e. overall dimensions do not allow developing a workable design for a small diameter well, with casing strings Du = 168 and 146 mm.

The force of the applied springs due to the small size, and a sufficiently large stroke, is not enough to maintain the operability of the valve both when it is opened and when closed.

The need to supply excess pressure to the annulus only to open the shutter, and to carry out a technological operation to supply the working fluid through the pipe string to the annulus, reduces the efficiency of the work.

The actuation of the valve to close is also problematic if there is excessive pressure in the pipe tubing string, since moving the sleeve to contact with the locking protrusion implies a pressure drop across it, but such a difference is not observed in the design structure, i.e. there is no hydraulic connection of the cavity under the sleeve with the annulus.

The technical result consists in the possibility of well development, by creating a hydrodynamic connection between the annulus and the axial channel of the pipe tubing through the circulation valve.

Development of deep wells is possible when equipping the tubing string with several identical devices spaced at the depth of the well, with the possibility of their successive opening and closing and the formation of a hydrodynamic connection. This is achieved by selecting the cross section of the annular spring, based on the calculated pressure drop at which the poppet valve opens.

The technical result is achieved using the proposed solution, comprising a housing with an axial channel and an annular groove in the middle part, in which the annular spring is located. The housing is equipped with two radial holes and seats with an axial channel provided with o-rings, the shutter is made in the form of two poppet valves, each equipped with a guide included in the axial channel of the seat, and a threaded end, with which each of the poppet valves is connected with a counter thread made in the body an annular spring mounted loosely in the annular groove of the housing.

An analysis of the inventive step showed that the combination of structural elements in the distinctive part of the claims giving the above technical result was not identified by available sources of scientific, technical and patent literature. Together with the known features of the present invention allows to solve the problem.

This gives reason to believe that the invention has an inventive step.

The invention is industrially applicable, since the experimental model of the device has passed comprehensive bench tests with positive results.

The design of the device is illustrated by drawings where:

- figure 1 - design of the circulation valve in the context in the initial position;

- figure 2 - design of the circulation valve at the time of the formation of the hydrodynamic connection between the annular space and the internal cavity of the device, when installed as part of an elevator pipe string;

- figure 3 - the relative position of the parts of the device with a cross section along the axis of the arrangement of shut-off valves.

The circulation valve consists of a housing 1, with an upper pipe 2 and a lower 3 connecting thread, for installation as part of an elevator pipe string.

In the axial channel 4 of the housing 1, an annular groove 5 and two radial holes are made in which saddles 6 are installed, with axial channels 7 and sealing rings 8 in the grooves. In the annular groove 5 of the housing 1, an annular spring 9 is freely installed, with threaded holes 10 in which the valves are in the form of poppet valves 11, which are pressed against the seating surface of the seats 6 due to the elastic properties of the annular spring 9.

Poppet valves 11 are provided with a guide cross 12, which they enter into the axial channels 7 of the seats 6.

Process valve operation

The valve is part of the pipe tubing, due to the connection with the pipes of the upper pipe 2 and lower 3 connecting thread, and lowers to a predetermined depth.

When applying excess pressure to the annular space of the well, the latter acts on the cross-sectional area of the poppet valves 11 installed in the saddles 6 of the housing 1, located opposite each other.

With the estimated axial force, the poppet valves 11 open from the seats 6, with elastic compression to the axis of the housing 1 by an annular spring 9.

The liquid from the annulus through the formed gap between the seat 6 and the poppet valve 11 enters the axial channel 4 of the housing 1 and then passes to the surface through the pipe lift string. After depressurization, due to the elasticity of the annular spring 9, the poppet valves 11 are pressed against the seating surfaces of the seats 6 with sealing rings 8 and isolate the axial channel 4 of the housing 1 from the annular space.

In the presence of excess pressure in the pipe lift string and the axial channel 4 of the housing 1, the poppet valves 11 are additionally pressed against the seat surface of the seats 6.

The pressure drop at which the poppet valves 11 are opened can be controlled by the calculation of the cross section of the annular spring 9 by calculation.

After closing the hydraulic connection of the axial channel 4 of the housing 1, with the annular space of the well, the latter can be operated in the mode of supplying formation fluid to the surface, immediately after the development of the wells.

Claims (1)

Technological circulation valve, comprising a housing with an upper connecting pipe and a lower thread, a radial hole with a seat and a spring-loaded shutter, characterized in that the housing is equipped with an internal annular groove and seats with sealing rings fixed rigidly in its radial openings, the shutter is made in the form of two disk valves, each equipped with a guide that moves movably into the axial channel of the seat, and a ring spring with threaded openings is freely installed in the annular groove iyami and poppet valves are provided with mating threads and is rigidly connected with the annular spring.

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