CN104895528B - Double pipe safety valve - Google Patents

Abstract

The invention relates to a double-pipe safety valve capable of establishing an annular circulation channel. A spring barrel and a flow pipe are connected to a hydraulic chamber. Two dynamic sealing components are matched between the inner wall of the spring barrel and the outer wall of the flow pipe to form a piston chamber. A power spring is placed in the chamber, and the spring cylinder is connected to the outer cylinder through an adapter, and the lower end of the outer cylinder is connected to the transfer joint. The lower end of the joint is connected with a liquid passing pipe, and a liquid injection hole is opened on the liquid passing pipe, and the lower end of the liquid passing pipe is connected and inserted into a sealing seat. The technical solution provided by the invention adds the function of establishing annular channel circulation on the basis of retaining the existing functions of the safety valve to shut off downhole overflow and blowout, so that it is not necessary to start and replace during water injection, polymer injection, chemical agents, etc. Pipe string, reduce operation cycle and save cost.

Description

Double pipe safety valve

technical field

The invention relates to a ground-controlled downhole safety valve used in oil and gas wells, in particular to a double-pipe safety valve capable of establishing an annular circulation channel.

Background technique

The downhole safety valve is a downhole tool used in oil and gas wells to prevent overflow and blowout caused by downhole fluid out of control. The working principle of the ground-controlled downhole safety valve is: hydraulic pressure is pumped through the ground hydraulic control pipeline, and the hydraulic pressure pushes the piston down, driving the flow tube downward to compress the spring, pushing the disc open, and opening the safety valve. When it needs to be closed, the hydraulic control pipeline is unloaded. When the hydraulic pressure is removed, the flow pipe goes up and separates from the valve disc under the action of the spring thrust, and the valve disc is closed under the action of the torsion spring to block the fluid passage.

The existing ground-controlled downhole safety valve does not have the ability to establish annulus channel circulation. When water injection, polymer injection, and chemical agent operations are performed on the oil well, the pipe string must be replaced, which has a long operation period and high cost.

Contents of the invention

In order to solve the problems of the existing downhole safety valve, the present invention aims to provide a ground-controlled double-pipe safety valve with reliable performance, which can meet the needs of water injection and chemical medicament injection without changing the pipe string.

In order to achieve the above object, the technical solution adopted in the present invention is: the spring barrel and the flow pipe are connected to the hydraulic chamber, and two dynamic seal assemblies are matched between the inner wall of the spring barrel and the outer wall of the flow pipe to form a piston chamber, and a piston chamber is placed in the piston chamber. Power spring, the spring cylinder is connected to the outer cylinder through the adapter. A liquid injection hole is opened on the liquid pipe and the liquid passage pipe, and the lower end of the liquid passage pipe is connected and inserted into the sealing seat. An opening assembly is sequentially installed in the space between the transfer joint, the liquid passing pipe and the insertion sealing seat; the lower joint is connected to the sliding sleeve seat.

Wherein, the valve clack pin in the valve clack assembly passes through the opening on the valve clack and the valve clack frame, so that the valve clack can rotate with the valve clack pin as the axis, and the valve clack torsion spring is also worn on the valve clack pin, The two arms of the torsion spring are buckled on the disc and the disc frame respectively.

Wherein, the middle part of the sliding sleeve is symmetrically provided with two rectangular grooves, and the locking block is installed in the rectangular grooves.

Among them, there are key grooves on the inner wall of the outer cylinder, which cooperate with the raised keys on the sliding sleeve seat during installation to transmit torque; the recessed part between the keys and the recessed part at the same position of the sliding sleeve seat form a rectangular, accommodating action The channel through which the arms of the barrel pass.

Wherein, the tail of the action cylinder is provided with a threaded hole, and the front end of the action claw is also provided with a corresponding threaded hole, and the two are connected by a pin to make them interlock.

Wherein, a balance plug cap and a balance plug rod are installed in the installation hole on the pressure relief seat, and a pressure relief spring is sleeved on the balance plug rod.

Wherein, the mounting hole of the pressure relief seat is provided with evenly distributed semicircular holes surrounding the center of the hole.

Among them, the cross-section of the pressure relief seat is designed to have a small distance between the upper and lower sides and a large distance between both ends, so as to ensure the flow area of the annular channel.

Wherein, the upper end and the lower end of the pressure relief seat are respectively provided with parallel and symmetrical limiting planes that cooperate with the two arms of the action claw to limit the rotation of the pressure relief seat, and the two arms of the action claw are respectively provided with steps that cooperate with the pressure relief seat.

Compared with the prior art, the technical solution provided by the present invention adds the function of establishing annular channel circulation on the basis of retaining the functions of the existing safety valve to shut off downhole overflow and blowout, so that water injection, polymer injection, chemical injection, etc. There is no need to change the string during the operation of chemicals, which reduces the operation cycle and saves costs.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Figure 2 is a schematic diagram of the structure of the sliding sleeve.

Figure 3 is a schematic structural view of the outer cylinder.

Fig. 4 is a structural schematic diagram of the pressure relief seat.

In the figure: 1 is the hydraulic chamber, 2 is the spring barrel, 3 is the dynamic seal assembly, 4 is the flow pipe, 5 is the power spring, 6 is the sealing seat, 7 is the adapter, 8 is the outer cylinder, 9 is the valve seat, 10 11 is the valve disc torsion spring, 12 is the valve disc pin, 13 is the valve disc, 14 is the balance plug, 15 is the sliding sleeve seat, 16 is the lock block, 17 is the sliding sleeve, 18 is the action cylinder, 19 20 is a transfer joint, 21 is a liquid pipe, 22 is a liquid injection hole, 23 is a pin, 24 is an action claw, 25 is a pressure relief seal, 26 is a pressure relief seat, 27 is a balance plug cap, and 28 is a Balance plug rod, 29 is a pressure relief spring, 30 is an insertion seal seat, and 31 is a lower joint.

detailed description

The present invention will be further described now in conjunction with accompanying drawing.

Referring to Figures 1 to 4, Figures 1 to 4 show an embodiment of the present invention, including a hydraulic chamber 1, a spring barrel 2, a dynamic seal assembly 3, a flow tube 4, a power spring 5, a seal seat 6, and an adapter 7. Outer cylinder 8, valve seat 9, disc holder 10, disc torsion spring 11, disc pin 12, disc 13, balance plug 14, sliding sleeve seat 15, locking block 16, sliding sleeve 17, action cylinder 18 , return spring 19, transfer joint 20, liquid pipe 21, liquid injection hole 22, pin 23, action claw 24, pressure relief seal 25, pressure relief seat 26, balance plug cap 27, balance plug rod 28, pressure relief spring 29 , Insert the sealing seat 30, the lower joint 31, etc., wherein:

The spring barrel 2 and the flow tube 4 are connected to the hydraulic chamber 1, and the inner wall of the spring barrel 2 and the outer wall of the flow tube 4 cooperate with two dynamic sealing components 3 to form a piston chamber, and 5 power springs and 2 springs are placed in the piston chamber. The barrel is connected to the outer barrel 8 through a 7 adapter, the lower end of the outer barrel 8 is connected to the valve disc assembly and the action assembly, the lower end of the transfer joint 20 is connected to the liquid pipe 21, and the liquid pipe 21 is provided with a liquid injection hole 22, and the liquid pipe The lower end of 21 is connected and inserted into the sealing seat 30. An opening assembly is installed in the space between the transfer joint 20 , the liquid passing pipe 21 and the insertion sealing seat 30 . The lower joint 31 is connected on the sliding sleeve seat 15 .

Among them, the valve disc assembly is composed of valve seat 9, valve disc frame 10, valve disc pin 12, valve disc 13, and valve disc torsion spring 11 in sequence;

Among them, the action assembly is composed of a sliding sleeve seat 15, a lock block 16, an action cylinder 18, a return spring 19, etc.;

Wherein, the opening assembly consists of pin 23, action pawl 24, pressure relief seal 25, pressure relief seat 26, balance plug rod 28, balance plug cap 27, pressure relief spring 29.

When the safety valve needs to be opened during use, high-pressure hydraulic oil is injected into the hydraulic channel A on the hydraulic chamber 1, and the hydraulic oil enters the two dynamic seal components 3 that are matched between the inner wall of the spring barrel 2 and the outer wall of the flow tube 4 constitute the piston chamber. Since the hydraulic acting area at the front of the flow tube 4 is slightly larger than the hydraulic acting area at the rear, the downward force generated by the hydraulic pressure is greater than the upward force, pushing the flow tube 4 down and compressing the power spring 5, and continuing to move downward to open the balance plug After 14, the pressure difference between the upper and lower sides of the valve disc 13 is balanced and the valve disc 13 is pushed back to open the safety valve. At this time, the hydraulic pressure continues to increase, the flow tube continues to touch the sliding sleeve 17 and pushes the sliding sleeve downward, and the locking block 16 installed in the rectangular groove in the middle of the sliding sleeve 17 also descends together. The locking block 16 pushes the action cylinder 18 downward, and the action cylinder 18 and the action claw 24 are linked together to descend. During the downward movement, the lower end of the action claw 24 first touches the cap of the balance plug 27 and pushes it downward, compressing the pressure relief spring 29, pushing the balance plug rod 28 away, and the lower end of the pressure relief seat 26 carries pressurized fluid Enter the upper end of the pressure relief seat 26 through the installation holes and evenly distributed semicircular holes to balance the upper and lower pressures of the pressure relief seat 26. The action claw 24 continues to descend, and the step B on the claw arm bears against the front end of the pressure relief seat 26, pushing the pressure relief seat 26 downward, so that the sealing surface C between the pressure relief seat 26 and the pressure relief seal 25 is opened, and a liquid injection mechanism is established. The hole 22 flows through the annular circulation channel D between the inner diameter of the pressure relief seat 26 and the outer diameter of the sliding sleeve seat 15 .

The embodiments of the present invention have been described above in conjunction with the accompanying drawings and the examples. The structures given in the examples do not constitute limitations to the present invention. Those skilled in the art can make adjustments as needed, within the scope of the appended claims All kinds of deformation or modification are within the scope of protection.

Claims (2)

1. a kind of tube safety valve, it is characterised in that：

Spring strut, flow duct are connected to hydraulic cavities, and dynamic sealing group at two is coordinated between the inwall of spring strut and the outer wall of flow duct Part constitutes and power spring is placed with piston chamber, piston chamber, and spring strut is connected to outer barrel, the connection of outer barrel lower end by adapter It is mounted with middle adapter, the space between adapter, middle adapter and outer barrel under flap assembly and action assembly, middle adapter End connected liquid pipe, crosses in liquid pipe and is provided with liquid injection hole, crossed liquid pipe lower end connection insertion seal receptacle；Middle adapter, cross liquid pipe and insert Enter and unlatching assembly is installed in the space between seal receptacle；Lower contact is connected on sleeve base；

Two rectangular channels are arranged with the middle part of the sliding sleeve, closing piece is arranged in rectangular channel；

There is keyway on the outer tube inner wall, raised key coordinates during installation and on sleeve base, transmit moment of torsion；Recessed portion between key The passage for dividing part composition rectangle, receiving ACTUATOR the two-arm recessed with sleeve base same position to pass through；

The afterbody of ACTUATOR is provided with screwed hole, and action pawl front end is also provided with corresponding screwed hole, and both make by pin connection It links；

It is provided with mounting hole on pressure release seat on balance cock cap peace weighing apparatus stopper rod, balance stopper rod and is cased with pressure release spring；

The uniform semicircle orifice at wound hole center is provided with the mounting hole of pressure release seat；

Pressure release seat Cross section Design is into distance is small up and down, two ends apart from big shape, to ensure the area of passage of annulus access；

Being rotated with the two-arm cooperation with acting pawl to limit pressure release seat for Parallel Symmetric is respectively equipped with pressure release seat top and bottom Spacing plane, action pawl two-arm on be respectively equipped with coordinate pressure release seat step.

2. a kind of tube safety valve according to claim 1, it is characterised in that：Flap pin in the flap assembly is passed through Perforate on flap and valve petal shelf, allows flap to be rotated by axle of flap pin, flap torsion spring is also through on flap pin, torsion spring Two-arm is buckled on flap and valve petal shelf respectively.