CN219492266U

CN219492266U - Downhole steel wire safety valve

Info

Publication number: CN219492266U
Application number: CN202223578414.1U
Authority: CN
Inventors: 余细波; 杨艳超; 张伟博
Original assignee: Shanghai Extrong Oilfield Technology Co ltd
Current assignee: Shanghai Extrong Oilfield Technology Co ltd
Priority date: 2022-12-30
Filing date: 2022-12-30
Publication date: 2023-08-08
Anticipated expiration: 2032-12-30

Abstract

The underground steel wire safety valve is provided with a second sealing component on the outer wall of the upper section of the flow tube and the inner wall of the connecting sleeve; the inner wall of the joint of the lower end of the spring cylinder and the upper end of the valve seat is provided with a sealing seat, the lower end of the flow pipe is sleeved with a sealing joint, and the outer wall of the upper end of the sealing joint and the lower end of the sealing seat can form metal seal; and the annular area of the second sealing component is larger than that of the metal seal; the lower end side wall of the spring cylinder is provided with a lower end small hole, and the external annular pressure can enter the annular cavity in the middle of the second sealing component and the metal seal through the lower end small hole. According to the utility model, the metal seal is opened by pushing the flow tube to move downwards, the pressure on the back surface of the valve plate enters into the space above the valve plate through the small hole below the spring cylinder, so that the balance of the upper pressure and the lower pressure of the valve plate is realized, and the resistance barrier is eliminated for the opening of the subsequent valve plate.

Description

Downhole steel wire safety valve

Technical Field

The utility model relates to an underground tool for oil and gas field development, in particular to an underground steel wire safety valve.

Background

The downhole oil pipe safety valve is a downhole tool which is arranged in an oil gas well, can be closed in an emergency way when fire alarm, pipeline rupture, irresistible natural disasters and the like occur in production facilities, and can prevent blowout, ensure oil gas well measures and production safety. When the underground safety valve fails and cannot be opened or closed, the oil and gas well cannot be produced normally, and the steel wire safety valve needs to be re-lowered at the moment to replace the conventional safety valve.

The working principle of controlling the underground safety valve at the ground surface is as follows: the hydraulic pressure is applied through the ground hydraulic control pipeline, the hydraulic pressure pushes the piston and the like to move downwards, the flow pipe is driven to move downwards to compress the spring, the valve clack is jacked up, and the safety valve is opened. When the valve is required to be closed, the hydraulic control pipeline is disconnected from the hydraulic pressure, the flow pipe moves upwards under the action of the spring pushing force and is separated from the valve clack, and the valve clack is closed under the action of the torsion spring to block the fluid channel.

Because of the importance and the specificity of the downhole oil pipe safety valve, once the downhole oil pipe safety valve breaks down, the safety of oil extraction operation is directly affected, and in order to avoid high cost caused by maintenance of the extracted oil pipe safety valve, the downhole oil pipe safety valve directly lowered into the downhole oil pipe safety valve to replace the broken down is usually adopted to work, so that normal oil extraction work is ensured.

The existing steel wire safety valve structure commonly used at present has the following three characteristics: 1) The hydraulic control piston part adopts a rod type piston structure, and the piston hole is not an annular hole structure, but is only one small hole distributed on one side in the circumferential radial direction. The structure has the defects that the structure occupies a relatively large volume space, and is not easy to realize in design for products with small outer diameter size; 2) When the power spring is installed, the power spring is sleeved on the surface of the corresponding outer diameter of the flow pipe in a free non-compression state, then the power spring is compressed through the step surface at the bottom of the inner hole of the spring barrel while rotating the spring barrel to be buckled when the spring barrel is connected with the outer barrel body to be buckled, and the power spring is compressed in place after the spring barrel is buckled in place. The design has the defects that when the spring cylinder is installed and buckled for connection, on one hand, the buckling torque is needed to be overcome, and on the other hand, the rebound force in the compression process of the power spring is needed to be overcome, so that the installation is time-consuming and labor-consuming, the operation is very inconvenient, and in addition, when the spring cylinder is disassembled, some potential safety hazards are caused by the rebound force of the power spring in a compressed state; 3) The valve plate is provided with a balance structure characteristic, namely, a small through hole with a sealing surface is designed on the back surface of the valve plate, then a cylindrical sealing plug is designed to be inserted into the through hole, and the sealing plug is tightly pressed through a pressure spring structure, so that the cylindrical sealing plug is tightly attached to the sealing surface of the small through hole to form a seal, when the seal is not needed, the cylindrical sealing plug is pushed open by overcoming the pressure force of the pressure spring and the fluid pressure on the back surface of the valve plate through downward movement of a flow pipe from the upper end surface of the valve plate, the sealing plug is separated from the sealing surface of the small through hole, and the space pressure balance between the back surface of the valve plate and the upper end surface is achieved. The disadvantage of this structure is that design can realize the structure of balanced function on the valve plate, has certain restriction requirement to the valve plate size, if the valve plate is too little, then difficult to realize in the design.

In order to better facilitate product installation and realize the design of small-size products, it is necessary to research an underground steel wire safety valve with a novel structure.

Disclosure of Invention

The utility model aims to solve the problems of the prior art and aims to provide an underground steel wire safety valve.

In order to achieve the purpose, in the technical scheme adopted by the utility model, a valve body comprises a connecting body, a connecting sleeve, a spring cylinder and a valve seat which are sequentially connected, the valve seat is connected with a rotatable valve plate through a torsion spring and a pin shaft, a flow pipe capable of axially moving and pushing up the valve plate is arranged in the valve body, and a second sealing component is arranged on the outer wall of the upper section of the flow pipe and the inner wall of the connecting sleeve; the inner wall of the joint of the lower end of the spring cylinder and the upper end of the valve seat is provided with a sealing seat, the lower end of the flow pipe is sleeved with a sealing joint, and the outer wall of the upper end of the sealing joint and the lower end of the sealing seat can form metal seal; and the annular area of the second sealing component is larger than that of the metal seal; the lower end side wall of the spring cylinder is provided with a lower end small hole, and the external annular pressure can enter the annular cavity in the middle of the second sealing component and the metal seal through the lower end small hole.

A first sealing component is arranged between the inner wall of the connecting sleeve and the outer wall of the flow pipe; the first sealing component and the second sealing component form a closed annular cavity and are communicated with external hydraulic control pressure through an upper end small hole; and the annular sealing area of the second seal assembly is greater than the annular area of the first seal assembly.

And a third sealing assembly is arranged between the outer wall of the sealing seat and the inner wall of the valve body.

The sealing joint is connected with the flow pipe through threads, and a fourth sealing component is arranged at the threaded connection position of the sealing joint.

The first to fourth sealing assemblies are composed of check rings, O-shaped rings and check rings.

Wherein, a power spring for resetting the flow tube is arranged in the spring cylinder; the upper end of the power spring is contacted with the lower end face of the large step on the outer wall of the middle section of the flow tube, and the lower end of the power spring is connected with the inner wall of the spring barrel.

The lower section of the flow pipe is provided with a small step which radially protrudes outwards, and a C-shaped baffle ring is clamped on the small step; the spring holder is fixed on the baffle ring, and the lower extreme of power spring contacts with the up end of spring holder.

Wherein, the internal diameter of the baffle ring is smaller than the external diameter of the small step, and forms interference fit.

The connecting body is provided with a connecting sleeve, wherein the connecting part of the connecting body and the connecting sleeve is provided with a supporting ring, and the upper side and the lower side of the supporting ring are sequentially provided with a V-shaped seal, a compression ring and two-end compression rings.

Wherein the metal seal is formed by matching a spherical surface and a conical surface.

Compared with the prior art, the utility model opens the metal seal by pushing the flow pipe downwards, the pressure on the back of the valve plate enters the space above the valve plate through the small hole below the spring cylinder, thereby realizing the balance of the upper pressure and the lower pressure of the valve plate and clearing resistance barriers for the opening of the subsequent valve plate; the spring seat and the baffle ring can avoid the resistance caused by the compression of the power spring to be overcome when the spring cylinder is installed later; the convenience and the safety of product assembly can be improved, and meanwhile, under the condition that the inner diameter and the outer diameter of the product are smaller, products meeting functional requirements can be conveniently designed.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the present utility model;

FIG. 2 is a cross-sectional view taken at B-B of FIG. 1;

FIG. 3 is a schematic diagram of an embodiment of the present utility model;

referring to the drawings, 1-connector, 2-retainer I, 3-O-ring I, 4-two-end compression ring, 5-compression ring, 6-V-seal, 7-support ring, 8-retainer II, 9-O-ring II, 10-connecting sleeve, 11-flow tube, 12-power spring, 13-spring barrel, 14-spring seat, 15-retainer ring, 16-retainer III, 17-O-ring III, 18-seal seat, 19-O-ring IV, 20-retainer IV, 21-seal joint, 22-valve seat, 23-torsion spring, 24-valve plate, 25-valve plate frame, 26-pin.

Detailed Description

The utility model will now be further described with reference to the accompanying drawings.

Referring to fig. 1-3, fig. 1-3 illustrate an embodiment of the present utility model, a downhole wireline safety valve. The valve body of this embodiment includes connector, adapter sleeve, spring cylinder and disk seat that connect gradually to be equipped with the hole structure that link up. The valve seat is connected with the rotatable valve plate through a torsion spring and a pin shaft, and a flow tube which can axially move and jack the valve plate is arranged in an inner hole of the valve body. The lower end of the valve seat is also connected with a valve plate frame, and the valve plate can move in a cavity of the valve plate frame.

A power spring for driving the flow tube to move downwards and then reset is arranged in the spring cylinder; the upper end of the power spring is contacted with the lower end face of the large step of the outer wall of the middle section of the flow tube, and the lower end of the power spring is connected with the inner wall of the spring barrel.

A second sealing component (sequentially composed of a check ring II, an O-shaped ring II and another check ring II) is arranged between the outer wall of the upper section of the flow pipe and the inner wall of the connecting sleeve; the inner wall of the joint between the lower end of the spring cylinder and the upper end of the valve seat is provided with a sealing seat, the outer wall of the lower end of the flow tube is sleeved with an upper section of a sealing joint, the outer wall of the upper section of the sealing joint and the lower end of the sealing seat can form metal sealing, and the sealing joint is formed by matching a spherical surface with a conical surface; the annular area of the second seal assembly is greater than the annular area of the metal seal. The side wall of the lower end of the spring cylinder is provided with a through lower end small hole, and the external annular pressure can enter the annular cavity between the two seals through the lower end small hole.

Because the sealing annular area of the second sealing component positioned at the upper end is larger, the pressure pulls the sealing joint upwards, so that the metal sealing surface between the sealing joint and the sealing seat is tightly attached. When the valve plate is pushed away but pressure exists on the back surface of the valve plate, the hydraulic control pressure can be applied to push the flow tube and the sealing joint to move downwards for a small distance so as to separate the metal sealing surface between the flow tube and the sealing seat, then the pressure on the back surface of the valve plate can pass through the small hole at the lower end of the spring cylinder and then enter the space between the inner wall of the spring cylinder and the outer wall of the flow tube and the space between the inner wall of the valve seat and the outer wall of the flow tube, and finally enter the space on the upper end surface of the valve plate, so that the pressure on the upper end surface and the lower end surface of the valve plate reach balance, the hydraulic control pressure is continuously applied, and the sealing joint can push the valve plate away under the condition of no pressure difference after continuously descending.

Further, a first sealing component (which sequentially consists of a retainer ring I, O-shaped ring I and another retainer ring I) is arranged between the inner wall of the connecting sleeve and the outer wall of the flow pipe; the first sealing component and the second sealing component form a sealing cavity of an annulus, and the annulus sealing area of the second sealing component is larger than that of the first sealing component, so that an annulus piston power mechanism is formed.

Further, a small step with a variable diameter and protruding outwards is arranged at the position of the outer diameter of the flow pipe, wherein the spring seat is used for compressing the power spring to a proper compression state, and the open C-shaped baffle ring is clamped into an inner hole at the lower end of the spring seat. Meanwhile, as the inner diameter of the baffle ring is smaller than the outer diameter of the step surface at the position, interference fit is formed, so that the power spring can be kept in a compressed state, the baffle ring can be clamped at the position and overcomes the rebound force of the compressed power spring, and the resistance caused by the compression of the power spring when the spring cylinder is installed later can be avoided.

Preferably, a third sealing component (sequentially composed of a check ring III, an O-shaped ring III and another check ring III) is arranged between the outer wall of the sealing seat and the inner wall of the valve body; the sealing joint is connected with the flow pipe through threads, and a fourth sealing component (composed of a check ring IV and an O-shaped ring IV) is arranged at the threaded connection part of the sealing joint; the joint of the connecting body and the connecting sleeve is provided with a supporting ring, and the upper side and the lower side of the supporting ring are sequentially provided with a V-shaped seal, a compression ring and compression rings at two ends (forming a V-shaped seal assembly), so that static seal is respectively realized.

Based on the structure, the oil pipe recovery safety valve is mainly used as a secondary safety valve in the oil pipe recovery safety valve. When the oil pipe recovery safety valve cannot work normally, firstly, a forced opening tool and a punching tool are respectively put in sequence to open a valve plate of the oil pipe recovery safety valve, and the oil pipe recovery safety valve hydraulic control piston system is communicated with the inside of the oil pipe; the upper end of the steel wire safety valve is respectively connected with a lock core tool and a feeding tool, the steel wire safety valve is put into the oil pipe recovery safety valve, and sitting and hanging positioning is completed through the lock core tool; at the moment, the V-shaped sealing component at the upper end of the steel wire safety valve is just in sealing fit with the sealing cylinder at the lower end of the oil pipe recovery safety valve.

After the operation preparation is finished, the hydraulic control system of the oil pipe recovery safety valve is directly utilized, hydraulic control pressure is injected into an annular sealed cavity formed by a first sealing component and a second sealing component between the flow pipe, the connecting body and the connecting sleeve through a small hole at the upper end of the connecting body, and the pressure generated by the fact that the sealing area at the lower end of the annular sealed cavity is larger pushes the flow pipe to descend and compresses the power spring; and meanwhile, the sealing joint is driven to descend, and finally, the valve plate is completely jacked up by the lower end part of the sealing joint. When the hydraulic control pressure is released to be zero, the flow pipe and the sealing joint assembly are reset under the action of the resilience force of the power spring and return to the initial position upwards, and the valve plate is in a closed state again under the reaction force of the torsion spring.

When oil pipe pressure exists on the back of the valve plate, the pressure of the upper end and the lower end of the valve plate needs to be balanced at first, and the specific measures are as follows: after the greater hydraulic control pressure is applied to push the flow tube and the sealing joint assembly to move downwards for a small distance, the metal sealing surface between the sealing joint and the sealing seat is separated, the pressure on the back surface of the valve plate enters into the upper end space of the valve plate through the small hole at the lower end of the spring cylinder, at the moment, the pressures at the upper end and the lower end of the valve plate reach balance, then the hydraulic control pressure is continuously increased, and the valve plate can be pushed away under the condition of no pressure difference by continuously moving downwards the sealing joint.

The embodiments of the present utility model have been described above with reference to the accompanying drawings and examples, which are not to be construed as limiting the utility model, but rather as modifications, variations or adaptations thereof may be made by those skilled in the art within the scope of the appended claims.

Claims

1. The utility model provides a steel wire relief valve in pit, the valve body is including connector, adapter sleeve, spring cylinder and the disk seat that connects gradually, and the disk seat passes through torsional spring, round pin axle and rotatable valve plate connection, is equipped with the flow tube that can axial displacement and jack up the valve plate in the hole of valve body, its characterized in that: the outer wall of the upper section of the flow pipe and the inner wall of the connecting sleeve are provided with second sealing components; the inner wall of the joint of the lower end of the spring cylinder and the upper end of the valve seat is provided with a sealing seat, the lower end of the flow pipe is sleeved with a sealing joint, and the outer wall of the upper end of the sealing joint and the lower end of the sealing seat can form metal seal; and the annular area of the second sealing component is larger than that of the metal seal;

the lower end side wall of the spring cylinder is provided with a lower end small hole, and the external annular pressure can enter the annular cavity in the middle of the second sealing component and the metal seal through the lower end small hole.

2. A downhole wireline safety valve according to claim 1, wherein: a first sealing component is arranged between the inner wall of the connecting sleeve and the outer wall of the flow pipe; the first sealing component and the second sealing component form a sealing cavity of an annulus and are communicated with external hydraulic control pressure through an upper end small hole, and the annular sealing area of the second sealing component is larger than that of the first sealing component.

3. A downhole wireline safety valve according to claim 1, wherein: a third sealing component is arranged between the outer wall of the sealing seat and the inner wall of the valve body.

4. A downhole wireline safety valve according to claim 1, wherein: the sealing joint is connected with the flow pipe through threads, and a fourth sealing component is arranged at the threaded connection part of the sealing joint and the flow pipe.

5. A downhole wireline safety valve according to any of claims 1-3, wherein: a power spring for resetting the flow tube is arranged in the spring cylinder; the upper end of the power spring is contacted with the lower end face of the large step on the outer wall of the middle section of the flow tube, and the lower end of the power spring is connected with the inner wall of the spring barrel.

6. The downhole wireline safety valve according to claim 5, wherein: the lower section of the flow pipe is provided with a small step which radially protrudes outwards, and a C-shaped baffle ring is clamped on the small step; the spring holder is fixed on the baffle ring, and the lower extreme of power spring contacts with the up end of spring holder.

7. The downhole wireline safety valve according to claim 6, wherein: the inner diameter of the baffle ring is smaller than the outer diameter of the small step, and interference fit is formed.

8. A downhole wireline safety valve according to claim 1, wherein: the junction of connector and adapter sleeve is equipped with the support ring, and the upper and lower both sides of support ring are equipped with V type seal, clamping ring and both ends clamping ring in proper order.

9. A downhole wireline safety valve according to claim 1, wherein: the metal seal is formed by matching a spherical surface and a conical surface.