CN1908365A - Control system of well mouth release valve - Google Patents

Abstract

The invention discloses a wellhead safety valve control system, which includes a pneumatic booster pump and a ground safety valve control circuit, and the ground safety valve control circuit includes a high-pressure needle valve, a one-way valve, a pressure gauge, and an accumulator, which are connected in sequence , and a relief valve is set between the check valve and the pressure gauge, one end of the high-pressure needle valve is connected to the pneumatic booster pump, one end of the accumulator is connected to the ground safety valve, and is connected to the pipeline gas source, and the single end of the ground safety valve control circuit A high-pressure needle valve is set between the directional valve and the pressure gauge, and a downhole safety valve control circuit is set between the pneumatic booster pump and the downhole safety valve. connected in sequence, and another branch is set between the check valve and the pressure gauge of the circuit, and the other end of the branch is connected to the ground safety valve control circuit between the check valve and the pressure gauge, and two branches are set on the branch One-way valve, a high-pressure needle valve is connected between the two one-way valves. The invention is safe and reliable.

Description

Wellhead safety valve control system

technical field

The invention relates to a device for extracting oil or natural gas from deep wells, in particular to a wellhead safety valve control system for oil or natural gas.

Background technique

At present, the opening pressure of the safety valves of most oil and gas wells in Northwest my country is around 15,000 psi (100 MPa), while the traditional hydraulic devices used in existing systems can only reach a maximum working pressure of 5,000 psi (35 MPa), which cannot meet the operating requirements. Since the site of use is a flammable and explosive place with a high concentration of natural gas, the explosion-proof level is required to be above EXD IIBT4. The existing system uses electro-hydraulic pumps and solenoid valves, which will cause the system to heat up and easily generate electric sparks during operation, which is a serious problem. potential safety hazards, and the existing technology can only control the surface safety valve, but cannot control the downhole safety valve. Oil and gas wells need to be kept open for a long time during production, which requires high pressure stability of the wellhead safety valve control system. The control valve in the existing system is a slide valve structure, and the leakage is too large. Maintain normal production of oil and gas wells. When the pressure fluctuation in the oil and gas pipeline exceeds the set range, the control system should immediately close the wellhead safety valve to prevent accidents. However, this function cannot be realized in the existing system.

Contents of the invention

The purpose of the present invention is to overcome the disadvantages of the above-mentioned technologies, and provide a safe and reliable wellhead safety valve control system that does not generate electric sparks, has high and low pressure limiting protection, and can realize remote control.

The purpose of the present invention is achieved like this:

A wellhead safety valve control system, including a high-pressure pump and a surface safety valve control circuit, the ground safety valve control circuit includes a stop valve, a one-way valve, a pressure gauge, and an accumulator, the four are connected in sequence, and the one-way valve An overflow valve is set between the gauge and the pressure gauge, one end of the shut-off valve is connected to the high-pressure pump, and one end of the accumulator is connected to the ground safety valve. The shut-off valve is a high-pressure needle valve, and the high-pressure pump is a pneumatic booster pump, which connection, a high-pressure needle valve is set between the one-way valve and the pressure gauge in the ground safety valve control circuit, and a downhole safety valve control circuit is also provided between the pneumatic booster pump and the downhole safety valve. Including high-pressure needle valve, check valve, pressure gauge and accumulator, the four are connected in sequence, and another branch is set between the check valve and pressure gauge of the circuit, and the other end of the branch is connected to the ground safety valve Between the one-way valve and the pressure gauge in the control circuit, two one-way valves are arranged on the branch, and a high-pressure needle valve is connected between the two one-way valves.

The ground safety valve control circuit of the present invention is further provided with a high and low pressure control circuit, including two air control valves, which are respectively connected between the check valve and the pressure gauge in the ground safety valve control circuit, and also includes a high-pressure pilot shut-off valve And a low-pressure pilot shut-off valve, one end of the two is connected with two air control valves respectively, a pressure reducing valve and a pressure gauge are set between the pneumatic booster pump and the pipeline air source, and the pipeline air source is decompressed as the drive The air source is connected to the pneumatic booster pump, and another air source branch is used as the control air source. Connection, the pipeline gas source is provided with a pressure gauge.

The wellhead safety valve control system of the present invention also includes an emergency shut-in circuit, which includes an air control valve and a three-way valve, two branches on the branch between the surface safety valve control circuit and the downhole safety valve control circuit The air control valve is connected between the two one-way valves, one end of the three-way valve is connected with the control air source, and the other end is connected with the air control valve.

Compared with the prior art, the wellhead safety valve control system of the present invention has the following positive effects:

1) Using pneumatic pump and pilot shut-off valve, no power is introduced into the whole control system, no electric spark is generated, and there is no potential safety hazard; at the same time, the output hydraulic pressure of the pneumatic booster pump can be adjusted arbitrarily, and it changes with the change of driving air pressure. And change, when the output pressure of the pneumatic booster pump reaches the set value, the pneumatic pump will automatically stop working, the system does not need to overflow, the oil temperature will not rise, it is absolutely safe and reliable; and it can meet the safety valves in oil and gas wells in some areas High cracking pressure required.

2) Both the high-pressure needle valve and the air-operated valve are zero-leakage stop valves, which are sealed with metal cones and can maintain zero-leakage for a long time under high pressure, so that the system can work stably for a long time.

3) High and low pressure control circuit is used to control the pipeline pressure exceeding the set pressure range caused by manual misoperation, pipeline burst, blockage, wax formation, freezing, etc., which can protect the safety of wellhead equipment and pipelines, as well as oil and gas resources, prevent pollution, and ensure the normal operation of the wellhead within a certain pressure range and stable production.

4) Set up a remote emergency shut-off circuit. When the wellhead equipment is abnormal during production, the staff can directly issue instructions in the duty room far away from the site to automatically shut down the entire wellhead equipment.

Description of drawings

Fig. 1 is a schematic diagram of the wellhead safety valve control system of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Please refer to Fig. 1, a wellhead safety valve control system, including a high-pressure pump 11, manual pumps 12, 13, a ground safety valve control circuit, the ground safety valve control circuit includes a stop valve 22, a one-way valve 32, a pressure gauge 62 , accumulator 82, the four are connected in sequence, and a relief valve 51 is set between the check valve 32 and the pressure gauge 62, one end of the shut-off valve 22 is connected to the high-pressure pump 11, and one end of the accumulator 82 is connected to the ground safety valve. The shut-off valve 22 is a high-pressure needle valve, the high-pressure pump 11 is a pneumatic booster pump, and is connected to the pipeline gas source, and a high-pressure needle is set between the check valve 32 and the pressure gauge 62 in the ground safety valve control circuit. type valve 24, a downhole safety valve control circuit is also provided between the pneumatic booster pump and the downhole safety valve, the circuit includes a high pressure needle valve 21, a check valve 31, a pressure gauge 61, an accumulator 81, four connected in sequence, and another branch is set between the one-way valve 31 and the pressure gauge 61 of the circuit, and the other end of the branch is connected to the ground safety valve control circuit between the one-way valve 32 and the pressure gauge 62, and the branch Two one-way valves 33, 34 are provided, and a high-pressure needle valve 23 is connected between the two one-way valves 33, 34.

A pressure reducing valve and a pressure gauge are arranged between the pneumatic booster pump and the pipeline gas source. The pipeline gas source is decompressed and connected to the pneumatic booster pump as a driving gas source, and another gas source branch is used as a control gas source.

The ground safety valve control circuit is further provided with a high and low pressure control circuit, including two air control valves 42, 43, respectively connected between the check valve 32 and the pressure gauge 62 in the ground safety valve control circuit, and also includes a high pressure pilot The shut-off valve 71 and a low-pressure pilot shut-off valve 72, one end of the high-pressure pilot shut-off valve 71 is connected with the pipeline air source, and the other end is connected with the air control valve 42 and the control air source, and one end of the low-pressure pilot shut-off valve 72 is connected with the pipeline air source The other end is connected with the air control valve 43 and the control air source, and the pipeline air source is provided with a pressure gauge 63 .

The wellhead safety valve control system also includes an emergency well shut-off circuit, which includes an air control valve 41 and a three-way valve 91, two branches on the branch between the ground safety valve control circuit and the downhole safety valve control circuit. The pipeline between the one-way valves 33 and 34 is connected with the air control valve 41 , one end of the three-way valve 91 is connected with the control air source, and the other end is connected with the air control valve 41 .

When the high-pressure needle valve 24 is opened, the surface safety valve control circuit is relieved, the surface safety valve is closed, the check valve 34 isolates the downhole safety valve control circuit, and the downhole safety valve will not be closed.

When the high-pressure needle valve 23 is opened, the downhole safety valve control loop and the ground safety valve control loop will simultaneously release pressure, and the downhole safety valve and the ground safety valve will be completely closed.

When the pipeline pressure is too high, the pilot shut-off valve 71 is turned on, so the control air source is sent to the air control valve 42, so that the air control valve 42 will open, the ground safety valve control circuit is depressurized, and the ground safety valve is closed.

When the pipeline pressure is too low, the pilot shut-off valve 72 is switched on, so the control air source is sent to the air control valve 43, so that the air control valve 43 will be opened, the ground safety valve control circuit is depressurized, and the ground safety valve is closed.

When it is necessary to shut down the well remotely, the operating room can directly control, operate the three-way valve 91, control the gas source to the air control valve 41, the air control valve 41 is opened, and the control circuit of the downhole and surface safety valve is relieved, so the downhole safety valve and ground safety valves are fully closed.

Because the high-pressure shut-off valves 21 and 22 as cut-off valves are installed before the high-pressure needle valves 23, 24 as unloading valves and the air control valves 41, 42, 43 in the downhole and surface safety valve control circuits, even if due to misoperation, forget Closing the high-pressure shut-off valves 21 and 22 will not affect the shut-in function.

Claims (3)

1. control system of well mouth release valve, comprise high-pressure pump, the surface safety valve (SSV) control loop, described surface safety valve (SSV) control loop comprises stop valve, one way valve, pressure meter, accumulator, four link to each other successively, and between one way valve and pressure meter, overflow valve is set, stop valve one end connects high-pressure pump, accumulator one end connects surface safety valve (SSV), it is characterized in that: described stop valve is a high-pressure needle valve, high-pressure pump is pneumatic booster pump, and be connected with the pipeline source of the gas, in described surface safety valve (SSV) control loop, establish a high-pressure needle valve in addition between one way valve and the pressure meter, also be provided with the storm valve control loop between described pneumatic booster pump and the storm valve, this loop comprises high-pressure needle valve, one way valve, pressure meter, accumulator, four link to each other successively, and between the one way valve in this loop and pressure meter, establish a branch in addition, the described branch other end is connected in the surface safety valve (SSV) control loop between the one way valve and pressure meter, this branch is provided with two one way valves, is connected with a high-pressure needle valve between described two one way valves.

2. control system of well mouth release valve as claimed in claim 1, it is characterized in that: described surface safety valve (SSV) control loop also is provided with a high-low pressure control loop, comprise two Pneumatic valves, be connected in the surface safety valve (SSV) control loop between the one way valve and pressure meter, also comprise a high pressure guide shut-off valve and a low pressure guide shut-off valve, both ends are connected respectively with two Pneumatic valves, between pneumatic booster pump and pipeline source of the gas, be provided with a reducing valve and pressure meter, the pipeline source of the gas is connected to pneumatic booster pump as driving source of the gas after reducing pressure, other has a source of the gas branch road as control source of the gas elder generation and height, low pilot-actuated valve links to each other respectively, be connected to two Pneumatic valves more respectively, the pipeline source of the gas is with high, low pilot-actuated valve connects, and described pipeline source of the gas is provided with pressure meter.

3. control system of well mouth release valve as claimed in claim 2, it is characterized in that: described control system of well mouth release valve also comprises urgent closing well loop, described urgent closing well loop comprises Pneumatic valve and three way cock, between described surface safety valve (SSV) control loop and the storm valve control loop in the branch pipeline between two one way valves be connected with described Pneumatic valve, described three way cock one end links to each other with the control source of the gas, and the other end links to each other with described Pneumatic valve.