Gas pipeline valve chamber trunk pipeline pipe burst monitoring, alarming and protecting device and method
Technical Field
The invention relates to the technical field of pipeline systems, in particular to a device and a method for monitoring, alarming and protecting a trunk pipeline of a gas pipeline valve chamber from pipe explosion.
Background
In the running process of the pipeline, natural gas leakage is caused by the rupture or fracture of the natural gas pipeline due to the reasons of pipeline corrosion, third party damage, construction quality and the like, and finally safety accidents of the oil and gas pipeline are brewed, so that great adverse effects are caused to the society and enterprises, and the serious threats are brought to the life and property safety of people around the pipeline. If the relevant information of whether the pipeline is broken or broken and the like is not mastered in time and is processed in time, the accident consequence is continuously aggravated, and serious environmental pollution and serious personal and property loss are caused.
For gas pipeline leakage caused by pipeline corrosion, third party damage, construction quality and the like, because natural gas is compressible fluid, the leakage monitoring cannot be carried out by using a method of a gas pipeline in the past engineering, the emergency cut-off function of a conveying system under the abnormal condition and the emergency cut-off function of a station access station cannot be realized, and the related problems can be found only when serious accidents such as natural gas leakage, fire or explosion and the like which can be observed by human eyes occur.
Disclosure of Invention
In order to solve the above problems, the present invention aims to provide a device and a method for monitoring and alarming the main pipeline pipe burst in a gas pipeline valve chamber at a faster speed and with a higher accuracy, so as to solve the problem that the existing natural gas pipeline cannot perform pipe burst detection alarm and set leakage alarm but false alarm is caused by pressure reduction during pipeline peak shaving.
The invention provides a gas transmission pipeline valve chamber trunk line pipeline pipe burst monitoring alarm and protection device, which comprises: the main pipeline is sequentially provided with a tee joint A, a line block valve and a tee joint B, and the line block valve is connected with the junction box through a cable;
one end of a bypass pipeline is connected with the tee joint A through a valve C, the other end of the bypass pipeline is connected with the tee joint B through a valve D, a valve E is arranged between the valve C and the valve D, a reserved interface is arranged on the bypass pipeline, a valve F is installed at the reserved interface, and the valve F is in a normally closed state;
a pressure leading pipeline A, one end of which is connected to a bypass pipeline between the tee joint A and the valve C through a valve A1, the other end of which is connected to the line cut-off valve through a valve A2, a pressure transmitter A1 and a pressure transmitter A2 are arranged on the pressure leading pipeline between the valve A1 and the valve A2, the pressure transmitter A1 and the pressure transmitter A2 are respectively connected with the pressure leading pipeline A through an instrument valve A1 and an instrument valve A2, and the pressure transmitter A1 and the pressure transmitter A2 are respectively connected with the junction box through cables;
a pressure-leading line B having one end connected to the bypass line between the three-way valve B and the valve D via a valve B1 and the other end connected to the line cut-off valve via a valve B2; a pressure transmitter B1 and a pressure transmitter B2 are arranged on a pressure leading pipeline between the valve B1 and the valve B2, the pressure transmitter B1 and the pressure transmitter B2 are respectively connected with the pressure leading pipeline B through an instrument valve B1 and an instrument valve B2, and the pressure transmitter B1 and the pressure transmitter B2 are respectively connected with the junction box through cables;
the controller comprises a data module, a calculation module, an alarm module and an execution module, wherein the input end of the controller is connected with the junction box through a cable, the output end of the alarm module is electrically connected with an alarm device, and the execution module is connected with an execution mechanism of the line block valve.
As a further development of the invention, the bypass line is connected to the high-pressure blow-down line via a valve G.
As a further improvement of the present invention, an instrument foot valve a1 is provided between the instrument valve a1 and the pressure-introducing line a, an instrument foot valve a2 is provided between the instrument valve a2 and the pressure-introducing line a, an instrument foot valve B1 is provided between the instrument valve B1 and the pressure-introducing line B, and an instrument foot valve B2 is provided between the instrument valve B2 and the pressure-introducing line B.
As a further improvement of the invention, an on-site pressure gauge is respectively connected to the pressure transmitter A1, the pressure transmitter A2, the pressure transmitter B1 and the pressure transmitter B2.
As a further development of the invention, the line block valve is a pneumatic valve.
As a further improvement of the invention, the alarm module and the execution module are both provided with a manual program closing button.
The invention also provides a monitoring, alarming and protecting method for pipe burst of a main pipeline of a gas transmission pipeline valve chamber, which comprises the following steps:
step 1: starting a controller of a gas pipeline valve chamber trunk pipeline pipe burst monitoring alarm and protection device;
step 2: the critical value of the pressure drop rate of a main pipeline pipe burst monitoring alarm and protection device of a gas pipeline valve chamber is set to be delta P on a controllersp(ii) a Continuously judging the pressure drop rate for n seconds, wherein n is an integral multiple of 5; the alarm delay action time is T seconds;
and step 3: opening a valve A1, an instrument valve A1, an instrument valve A2, an instrument root valve A1 and an instrument root valve A2 between the upstream of a bypass pipeline and the pressure transmitter A1 and the pressure transmitter A2 respectively, opening a valve B1, an instrument valve B1, an instrument valve B2, an instrument root valve B1 and an instrument root valve B2 between the downstream of the bypass pipeline and the pressure transmitter B1 and the pressure transmitter B2 respectively, simultaneously starting a timing program of a controller, transmitting pressure signals collected by the pressure transmitter A1, the pressure transmitter A2, the pressure transmitter B1 and the pressure transmitter B2 to the controller through cables, and recording a sampling time tag by the controller;
and 4, step 4: the controller calculates the average value P of the sampling pressure of the four pressure transmitters within n seconds through the formula (1)i,
Wherein, Pt: sampling pressure at the time t; pi: the average value of the sampling pressure of the four pressure transmitters within n seconds;
and 5: the controller calculates the pressure drop rate of 60 seconds before and after the four pressure transmitters by formula (2),
wherein, Pt: sampling pressure at the time t; delta Pi: a rate of pressure drop;
step 6: the controller judges the delta PspAnd Δ PiAnd recording the number k of times that the pressure drop rate continuously exceeds a set value, wherein the initial value of k is 0,
when Δ Pi≥ΔPspWhen k is greater than 1;
when Δ Pi<ΔPspWhen k is equal to 0, the value of k is initialized to 0;
and 7: the controller judges the magnitude of the pressure drop rate continuously exceeding a set value number k and the continuous sampling number n/5: when in use
When the alarm is not sent, the alarm is sent;
and 8: after the controller gives an alarm, starting an alarm delay action timer to start timing, and if the timing period is intervened, stopping timing and resetting the alarm delay action timer;
and step 9: when the time of the alarm time-delay action timer reaches T seconds, an execution module of the controller controls to close a line cut-off valve at the upstream and downstream of the pipe explosion position, a valve C, a valve D and a valve E on a bypass pipeline are opened, an accident pipeline is isolated, the alarm time-delay action timer is reset, and the alarm time-delay action timer is closed.
As a further improvement of the invention, in step 8, the manual shut-down program button comprises an alarm module and an execution module for manually shutting down the controller.
As a further improvement of the invention, after a program button of the alarm module is manually closed, the alarm time-delay action timer is reset and stops working, an incoming or outgoing ESDV valve in the direction of the accident pipeline is automatically closed, and the accident pipeline is isolated.
As a further improvement of the invention, after the manual program closing button of the execution module is manually closed, the alarm is maintained, and the automatic valve closing program is shielded.
The invention has the beneficial effects that: the gas transmission pipeline valve chamber main line pipeline pipe burst monitoring alarm and protection device is arranged on a gas transmission pipeline main line, pipe burst leakage of the gas transmission pipeline can be monitored more accurately and timely according to the pipe burst monitoring alarm and protection method, measures are taken to isolate an accident pipeline, operation safety of the gas transmission pipeline and safety of surrounding personnel and property are improved, and serious environmental pollution and safety accidents are avoided.
Drawings
Fig. 1 is a schematic structural view of a pipe burst monitoring, alarming and protecting device for a main pipeline of a gas transmission pipeline valve chamber according to an embodiment of the invention;
fig. 2 is a flowchart of a pipe burst monitoring alarm and protection method for a main pipeline of a gas pipeline valve chamber according to an embodiment of the present invention.
In the figure, the position of the upper end of the main shaft,
1. a trunk line conduit; 2. a tee joint A; 3. a line block valve; 4. a tee joint B; 5. a bypass line; 6. a pressure-leading line A; 7. a pressure-leading line B; 8. a valve C; 9. a valve D; 10. a valve E; 11. a valve F; 12. a valve A1; 13. a valve A2; 14. a valve B2; 15. a valve B1; 16. pressure transmitter a 1; 17. pressure transmitter a 2; 18. pressure transmitter B1; 19. pressure transmitter B2; 20. meter valve a 1; 21. meter valve a 2; 22. meter valve B1; 23. meter valve B2; 24. meter root valve a 1; 25. meter root valve a 2; 26. meter root valve B1; 27. meter root valve B2; 28. a junction box; 29. and a valve G.
Detailed Description
The present invention will be described in further detail below with reference to specific embodiments and with reference to the attached drawings.
Embodiment 1, as shown in fig. 1, a pipe explosion monitoring, alarming and protecting device for a main pipe of a gas transmission pipe valve chamber according to an embodiment of the present invention includes:
the main pipeline 1 is sequentially provided with a tee joint A2, a line block valve 3 and a tee joint B4, and the line block valve 3 is connected with the junction box 28 through a cable;
one end of a bypass pipeline 5 is connected with the tee joint A2 through a valve C8, the other end of the bypass pipeline is connected with the tee joint B4 through a valve D9, a valve E10 is arranged between the valve C8 and the valve D9, a reserved interface is arranged on the bypass pipeline 5, a valve F11 is installed at the reserved interface, and the valve F11 is in a normally-closed state;
one end of a pressure leading pipeline A6 is connected to a bypass pipeline 5 between the tee joint A2 and the valve C8 through a valve A112, the other end of the pressure leading pipeline is connected to the line block valve 3 through a valve A213, a pressure transmitter A116 and a pressure transmitter A217 are arranged on the pressure leading pipeline between the valve A112 and the valve A213, the pressure transmitter A116 and the pressure transmitter A217 are respectively connected with the pressure leading pipeline A6 through an instrument valve A120 and an instrument valve A221, and the pressure transmitter A116 and the pressure transmitter A217 are respectively connected with a 28 junction box through cables;
a pressure-leading line B7 having one end connected to the bypass line 5 between the three-way valve B4 and the valve D9 via a valve B115 and the other end connected to the line cut-off valve 3 via a valve B214; a pressure transmitter B118 and a pressure transmitter B219 are arranged on a pressure leading pipeline between the valve B115 and the valve B214, the pressure transmitter B118 and the pressure transmitter B219 are respectively connected with the pressure leading pipeline B7 through an instrument valve B122 and an instrument valve B223, and the pressure transmitter B118 and the pressure transmitter B219 are respectively connected with the junction box 28 through cables;
the controller comprises a data module, a calculation module, an alarm module and an execution module, wherein the input end of the controller is connected with the junction box 28 through a cable, the output end of the alarm module is electrically connected with the alarm device, and the execution module is connected with an execution mechanism of the line cut-off valve 28. The data module receives pressure values measured by the four pressure transmitters through the data interface, outputs the pressure values to the calculation module for calculation and analysis, and the output result of the calculation module is used as a condition for triggering the alarm module and the execution module.
Further, the bypass line 5 is connected to the high pressure vent line via a valve G29.
Further, a meter root valve a 124 is provided between the meter valve a 120 and the pressure leading line A6, a meter root valve a 225 is provided between the meter valve a 221 and the pressure leading line A6, a meter root valve B126 is provided between the meter valve B122 and the pressure leading line B7, and a meter root valve B227 is provided between the meter valve B223 and the pressure leading line B7.
Further, a local pressure gauge is connected to each of the pressure transmitter a 116, the pressure transmitter a217, the pressure transmitter B118 and the pressure transmitter B219, so that the pressures of the upstream and downstream of the line block valve 3 can be conveniently detected and checked.
Further, the line cut-off valve 3 is a pneumatic valve.
Furthermore, the alarm module and the execution module are respectively provided with a manual program closing button, so that the alarm device and the linkage protection device can be manually controlled, and the pipeline of an operator can be conveniently checked and confirmed.
As shown in fig. 2, the invention also provides a pipe burst monitoring, alarming and protecting method for a main pipeline of a gas pipeline valve chamber, which comprises the following steps:
step 1: starting a controller of a gas pipeline valve chamber trunk pipeline pipe burst monitoring alarm and protection device;
step 2: the critical value of the pressure drop rate of a main pipeline pipe burst monitoring alarm and protection device of a gas pipeline valve chamber is set to be delta P on a controllersp(ii) a Continuously judging the pressure drop rate for n seconds, wherein n is an integral multiple of 5; the alarm delay action time is T seconds;
and step 3: opening a valve A1, an instrument valve A1, an instrument valve A2, an instrument root valve A1 and an instrument root valve A2 between the upstream of a bypass pipeline and the pressure transmitter A1 and the pressure transmitter A2 respectively, opening a valve B1, an instrument valve B1, an instrument valve B2, an instrument root valve B1 and an instrument root valve B2 between the downstream of the bypass pipeline and the pressure transmitter B1 and the pressure transmitter B2 respectively, simultaneously starting a timing program of a controller, transmitting pressure signals collected by the pressure transmitter A1, the pressure transmitter A2, the pressure transmitter B1 and the pressure transmitter B2 to the controller through cables, and recording a sampling time tag by the controller;
and 4, step 4: the controller calculates the average value P of the sampling pressure of the four pressure transmitters within n seconds through the formula (1)i,
Wherein, Pt: sampling pressure at the time t; pi: the average value of the sampling pressure of the four pressure transmitters within n seconds;
and 5: the controller calculates the pressure drop rate of 60 seconds before and after the four pressure transmitters by formula (2),
wherein, Pt: sampling pressure at the time t; delta Pi: a rate of pressure drop;
step 6: the controller judges the delta PspAnd Δ PiAnd recording the number k of times that the pressure drop rate continuously exceeds a set value, wherein the initial value of k is 0,
when Δ Pi≥ΔPspWhen k is greater than 1;
when Δ Pi<ΔPspWhen k is equal to 0, the value of k is initialized to 0;
and 7: the controller judges the magnitude of the pressure drop rate continuously exceeding a set value number k and the continuous sampling number n/5: when in use
When the alarm is not sent, the alarm is sent;
and 8: after the controller gives an alarm, starting an alarm delay action timer to start timing, and if the timing period is intervened, stopping timing and resetting the alarm delay action timer;
and step 9: when the time of the alarm time-delay action timer reaches T seconds, an execution module of the controller controls to close a line cut-off valve at the upstream and downstream of the pipe explosion position, isolate an accident pipeline from a station yard, clear the alarm time-delay action timer, and close the alarm time-delay action timer.
Further, in step 8, human intervention includes manually turning off the alarm module of the controller and manually turning off the program button of the execution module.
Furthermore, after a manual closing program button of the alarm module is manually closed, the alarm time-delay action timer is reset and stops working, an incoming or outgoing ESDV valve in the direction of the accident pipeline is automatically closed, and the accident pipeline and a station yard are isolated.
Furthermore, after a manual program closing button of the execution module is manually closed, an alarm is kept, and the automatic valve closing program is shielded.
When in specific use:
when the gas transmission pipeline is filled with high-pressure natural gas, if a certain place is broken or ruptured, at the moment, a large amount of gas in the pipeline at the upstream and downstream of the point leaks out from the point to cause the pressure of the pipeline at the upstream and downstream to be rapidly reduced, the pressure values of the pipeline are detected by two pressure transmitters respectively arranged at the upstream and downstream of a bypass pipeline of a main pipeline pipe burst monitoring alarm and protection device of a gas transmission pipeline valve chamber, a controller data module receives the pressure values, calculates the pipeline pressure values and the pressure drop rate through a calculation module, compares the pipeline pressure values and the pressure drop rate with a preset pressure drop critical value, when the pressure drop rate is greater than the preset pressure drop rate critical value in the sampling times of continuous judgment time, an alarm module gives an alarm and starts an alarm delay action timer, a field operator can secondarily confirm the pipeline problem during the alarm, and judges whether to manually close the alarm delay action timer according to the actual situation, whether the pipeline has problems or not is continuously verified, and at the moment, an operator can also manually close a manual closing program button of the execution module, so that the problem that the normal operation of the gas pipeline is influenced because the execution mechanism closes the line block valves on the upstream and the downstream of the pipe explosion position due to false alarm is prevented; under the condition that no personnel confirms or problems are confirmed, the alarm delay action timer reaches a preset upper limit (for example, set to 120 seconds), the controller execution module can automatically control the execution mechanism to close the line cut-off valves at the upstream and downstream of the pipe explosion position, isolate an accident pipeline from a station yard, clear the alarm delay action timer and close the alarm delay action timer.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.