RU2459067C1 - Device for wellhead sealing - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: invention refers to oil and gas industry, namely to device designed for wellhead sealing that can be used in the course of construction, oil and gas wells repair as well as accidents elimination. The device includes guide rod 1 that has support elements 2 on it, block assemblies 3 and shut-off assemblies 4. Support elements 2 are done in a form of collars that embrace guide rod 1. Block assemblies 3 contain spring-loaded bushes 6 with levers 15 kinematically connected to them on the ends of which there are eccentrics performed in a form of rollers 8. Shut-off assembly 4 is done in a form of movable shutters 7 kinematically connected to bushes 9 with provision of overlapping the inner section of well 10. Note that the lower part of guide rod 1 is done in a form of a pin 11 that is located on one axis with rigidly connected pipeline 12 on the upper end of which there is a valve 13. There is a hole 14 in the side surface of pipeline lower part. Note that shut-off assembly 4 is attached above the said hole.

EFFECT: increase of reliability of its attachment inside the well, extension of possibilities due to provision of controllable formation fluid extraction after closing the well.

9 cl, 7 dwg

Description

The invention relates to the gas and oil industry and can be used in the process of construction and repair of oil and gas wells, as well as in emergency situations for sealing the mouth of the wells during the elimination of gas, oil and other emissions under the influence of the pressure of the liquid-gas medium during mining.

A check valve for a drill string [1] is known, including a housing consisting of a nipple and a sub connected by a threaded connection, a composite saddle installed between them in the form of a sleeve forming an annular cavity with the sub, and an elastic elastomeric element placed in the cavity with the possibility of interaction with an annular protrusion of the cylindrical sleeve and nipple, as well as a disk-shaped locking element located on the side of the latter and in contact with the saddle, containing a rod extending along the axis of the sub in the tail Asti which a spring, biasing the valve plug against the valve seat, and a sub flow channel formed ribs, wherein the rod is formed as a central shaft and the sleeve and the ribs connect them together, the spring arranged in the cylindrical annular space between the shroud and sub.

The known device [1] is used to block drill pipes made in the form of a non-return valve when drilling, changing tools and repairing wells to prevent flowing of wells.

A device for sealing the wellhead [2] is also known, comprising a cylindrical body with a central axial stepped and radial channels, as well as connecting threads at the ends, a spring-loaded lower and upper saddles installed in the housing, and a ball locking member axially mounted between them to rotate channel and a groove on the outer surface, the axis of symmetry of which passes through the center of the ball locking element and is perpendicular to the axis of the channel in it, the rotation node of the ball locking body in the form of FIG. the coupling located in the radial channel of the housing, and the fixing unit in the form of a centering sleeve, support crackers and a retaining ring, the device is also equipped with a metering and pressure relief unit in the form of a controlled valve made with the possibility of interaction with a control key located above the main ball locking element additional spherical locking body with spring-loaded lower and upper saddles, nodes of its rotation and fixation, removable plug and spacer sleeve with radial channels on the side surface, p In addition, three radial channels are made in the casing, one of which is made under the lower saddle of the main spherical locking element, has a stepped shape with the smallest inner diameter on the side of the central axial channel of the casing and is designed to accommodate a controlled valve, the second is made over the fixation unit of the main spherical a locking body and serves to place in it a knot of rotation of an additional ball locking body, and the third serves to accommodate a removable plug in it and is made between the upper seat and the fixation unit of the main spherical locking element, while the spacer sleeve is installed between the latter and the stepped radial channel is made with internal threads, except for the step with the smallest internal diameter, and the controlled valve is made in the form of a cylindrical tube with an external thread on the lateral surface, reciprocal internal thread on the middle stage of the radial channel, which is installed in it with the possibility of axial movement, while the plug is made with through axial channels and splines m compound for controlling the valve at the outer end.

Closest to the technical nature of the proposed device is a known device for guiding blowout equipment at the mouth of a gushing well [3], comprising a housing, fixing elements of the housing relative to the casing at the mouth of the flowing well, a hydraulic drive for moving said fixing elements and sealing elements of the housing relative to said casing pipes, characterized in that on the inner surface of the casing is made annular bore, the hydraulic drive ne The placement of the locking elements is made in the form of an annular piston with a double-sided rod installed in the annular bore of the housing with the possibility of forming limited by the surfaces of the rod, piston and the housing, the piston return cavity for fixing the housing relative to the casing, the sealing elements of the housing relative to the casing are made in the form of preventer and placed above the hydraulic actuator displacement of the fixing elements of the housing relative to the casing, while the piston part of the rod is placed and in the upper portion of the housing to provide a sealing protection elements from thermal and mechanical action on them to targeting closure BOP on the wellhead flowing. The known device [3] is used to eliminate gas and oil fountains.

The disadvantages of the known devices [1, 2, 3] are the low reliability of fastening inside the well, as well as limited capabilities during operation.

The technical result, which consists in eliminating the disadvantages of the prototype [3], namely, increasing the reliability of fastening the device inside the well and expanding capabilities by providing controlled selection of liquid and / or gas medium after locking the well, is achieved in the proposed device for sealing the wellhead containing a guide the rod on which the supporting elements, locking nodes and locking nodes are located, in that the supporting elements are made in the form of annular clamps covering the guide rod with the possibility of fixing the position, the locking assemblies contain spring-loaded bushings located on the guide rod with kinematically connected levers, eccentrics made in the form of rollers are fixed at their ends, and the locking assembly is made in the form of movable wings, kinematically connected with the corresponding bushings, ensuring working the overlapping position of the internal section of the well, while the lower part of the guide rod is made in the form of a pin, on the same axis with which the pipeline is rigidly fixed, on the upper m end of which is installed the valve, and the side surface of the lower portion of an opening of the pipeline, wherein the latch assembly is mounted over said opening.

At the same time, a notch is made on the outer surface of the eccentric rollers to ensure mechanical contact with the inner surface of the well pipe in working condition, the levers of the locking nodes are symmetrically in the cross section of the nodes, and each locking node contains three levers and three rollers.

The technical result is also achieved by the fact that the device contains two locking nodes installed on the pipeline, two locking nodes are located under the locking nodes on the guide rod pin, and a third locking node is installed above the locking nodes on the guide rod pipeline.

Improving the reliability of overlapping the cross section of the well is also achieved by the fact that the locking unit contains three movable leaves symmetrically located around the circumference.

Ensuring the convenience of inserting the guide rod into the well is achieved by the fact that the weight of the device P _device. satisfies condition P _device > F _push. where F is a _push. - the value of the total buoyant force acting on the device with the introduction of the guide rod at the wellhead.

An additional increase in the reliability of overlapping the well section is achieved by the fact that the sealing elements are located along the outer contour of the movable flaps and in the zones of their mutual overlap.

Improving operational capabilities is achieved by the fact that it contains an electromechanical control unit and vertical traction kinematically connected with the levers of the locking nodes and with the movable leaves of the locking nodes.

The invention is illustrated by drawings,

where figure 1 shows the device when inserting it into the well to overlap its bore;

figure 2 shows the device in working condition with the overlap of the borehole;

figure 3 shows the image of the locking node (plan view);

figure 4 shows a photograph of the locking unit (top view);

figure 5 shows a photograph of the locking unit (side view);

figure 6 shows a photograph of the support element (top view);

Fig.7 shows a photograph of the spring of the locking assembly.

The device (figure 1, 2) contains a guide rod 1, on which are located the supporting elements 2, locking nodes 3 and locking nodes 4.

The supporting elements 2 are made in the form of annular clamps (Fig.6), covering the guide rod 1 with the possibility of fixing the position.

The locking nodes (1, 2, 4, 5) contain located on the guide rod 1 spring-loaded by means of springs 5 (Fig. 7) of the sleeve 6 with kinematically connected levers 15, at the ends of which are mounted eccentrics made in the form of rollers 8 .

The locking node 4 (Fig.1, 2, 3) is made in the form of movable flaps 7, kinematically connected with the corresponding bushings 9 with the provision in the working position of the overlap of the internal section of the well 10.

The lower part 11 of the guide rod 1 (figure 1, 2) is made in the form of a pin, on the same axis with which the pipe 12 is rigidly fixed, the valve 13 is installed on its upper end, and an opening 14 is made in the side surface of the lower part of the pipeline, while the shut-off the node 4 is fixed above the hole 14.

A notch is made on the outer surface of the eccentric rollers 8 (not shown in the drawings) to ensure that mechanical contact with the inner surface of the borehole pipe 10 is in working condition.

The levers 15 of the locking nodes 3 are located symmetrically in the cross section of the said nodes.

Each locking unit 3 contains three levers 15 and three rollers 8.

Figure 1, 2 shows a variant of the device, which contains two locking node 4 mounted on the pipe 12.

Under these locking nodes 4 on the guide rod 1 there are two locking nodes 3, and above the locking nodes 4 on the pipe 12 of the guide rod 1 there is a third locking node 3.

The locking node 4 contains three symmetrically arranged around the circumference of the movable sash 7.

Device weight P _device satisfies condition P _device > F _push. where F is a _push. - the value of the total buoyant force acting on the device with the introduction of the guide rod 1 at the wellhead 10.

Sealing elements 16 and 17 are located along the outer contour of the movable flaps 7 and in the zones of their mutual overlap.

The device also contains an electromechanical control unit 18 and vertical rods 19, kinematically connected via hinges (not shown) with levers 15 of the locking nodes 3 and with the movable leaves 7 of the locking nodes 3. The rods 19 pass through holes 20 in the leaves 7, with which they are also connected through the hinges (not shown in the drawings) without violating the tightness when closing the leaves 7. The presence of additional hinges 21 allows the leaves to deviate upward.

The output of the control unit 18 is connected to the control input of the valve 13, designed for controlled selection of liquid and / or gas medium.

The device operates as follows.

The guide rod 1 of the device is guided at the wellhead 10 using a lifting mechanism (not shown in the drawings). When the lower part 11 of the guide rod 1 gets into the casing of the well, since the weight of the device is P _device. satisfies condition P _device > F _push. where F is a _push. - the value of the total buoyant force acting on the device, the device goes down. In this case, the levers 15 of the locking nodes 3 and the movable leaves 7 of the locking nodes 4 are in the lowest position and do not impede the movement of the liquid and / or gas medium from the well 10.

After the device is completely immersed in the well, the electromechanical control unit 18 by means of movable rods 19 moves the levers 15 of the locking nodes 3 and the movable leaves 7 of the locking nodes 4 to the upper position. At the same time, the pressure of the liquid and / or gas medium flow from the well acts on the levers 15 and the shutter 7 from the bottom and they completely deviate to their highest position.

The rollers 8, the surface of which is made with a notch, come into contact with the inner surface of the pipe 10.

The rollers 8 are essentially eccentrics (the axis of rotation of the rollers is offset from their geometric center by a value of 5).

When the levers 15 are deflected upwards, the rollers rotate around their displaced axis and reliably “jam” with the levers 15 the device inside the well 10. The springs 5 perform a compensating role for the three levers 15.

The flaps 7 of the locking nodes 4, turning on hinges 21, move up and close the channel of the well 10 by mutual overlap and due to the presence of sealing elements 16 and 17, and therefore, block the path to the flow of liquid and / or gas medium.

The presence of two sequentially installed vertically locking nodes 4 increases the reliability of the overlap of the channel of the well 10.

The presence of the hole 14 allows the flow of liquid and / or gas to flow into the pipe 12 and rise to the valve 13. If the valve 13 is closed, the flow of the liquid and / or gas will be completely stopped, i.e. well 10 will be completely plugged.

The valve 13 allows for controlled and controlled selection of liquid and / or gas medium from the well 10. In this case, the selection is controlled from the control unit 18.

Parts and components of the device are made of high strength steel.

The device has been tested and has shown high reliability and ease of use.

Information sources

1. RF patent №2107805, IPC ЕВВ 34/06 from 08/26/1996.

2. RF patent №2124114, IPC ЕВВ 33/03 of 04.15.1998.

3. RF patent №2098598, IPC ЕВВ 33/06 dated 05.09.1995.

Claims (9)

1. A device for sealing the wellhead containing a guide rod, on which there are supporting elements, locking nodes and locking nodes, characterized in that the supporting elements are made in the form of annular clamps, covering the guide rod with the possibility of fixing the position, the locking nodes contain located on the guide spring-loaded bushings with kinematically connected levers, at the ends of which eccentrics are made in the form of rollers, and the locking unit is made in the form of movable ok, kinematically connected with the corresponding bushings to ensure that in the working position overlapping the internal section of the well, the lower part of the guide rod is made in the form of a pin, on the same axis with which the pipeline is rigidly fixed, at the upper end of which a valve is installed, and in the side surface of the lower part a hole is made in the pipeline, the locking unit being fixed above said hole. 2. The device according to claim 1, characterized in that a notch is made on the outer surface of the eccentric rollers to ensure that mechanical contact with the inner surface of the well pipe is operational. 3. The device according to claim 1, characterized in that the levers of the locking nodes are located symmetrically in the cross section of the said nodes. 4. The device according to claim 3, characterized in that each locking unit contains three levers and three rollers. 5. The device according to claim 1, characterized in that the device contains two locking nodes installed on the pipeline, two locking nodes are located under said locking nodes on the guide rod, and a third locking node is installed above the locking nodes on the guide rod pipeline. 6. The device according to claim 1, characterized in that the locking unit comprises three movable leaves symmetrically arranged around the circumference. 7. The device according to claim 1, characterized in that the weight of the device P _device. satisfies condition P _device > F _push. where F is a _push. - the value of the total buoyant force acting on the device with the introduction of the guide rod at the wellhead. 8. The device according to claim 6, characterized in that the sealing elements are located along the outer contour of the movable flaps and in the zones of their mutual overlap. 9. The device according to claim 1, characterized in that it contains an electromechanical control unit and vertical traction kinematically connected with the levers of the locking nodes and with the movable leaves of the locking nodes.

Images