CN216591088U

CN216591088U - Pressure adjusting device for natural gas entering network

Info

Publication number: CN216591088U
Application number: CN202122515541.6U
Authority: CN
Inventors: 叶忠健
Original assignee: Yichang Medium Combustion City Gas Development Co ltd
Current assignee: Yichang Medium Combustion City Gas Development Co ltd
Priority date: 2021-10-19
Filing date: 2021-10-19
Publication date: 2022-05-24
Anticipated expiration: 2031-10-19

Abstract

The pressure regulating device of the natural gas of the network inlet comprises a natural gas inlet pipeline, wherein an odorizing device, an outlet vent valve, a chromatographic analysis connecting pipe and a flowmeter are communicated on the inlet pipeline, two PID valves are communicated on the inlet pipeline, the inlet pipeline is communicated with a gas accumulator through a first branch pipe between the two PID valves, pressure sensors are communicated with two ends of the PID valves, each pressure sensor is connected with an input end of a controller, and the PID valves are connected with a control output end. The natural gas pressure balance control method is used for solving the problem that adverse effects are brought to pipe network parts due to natural gas pressure unbalance.

Description

Pressure adjusting device for natural gas entering network

Technical Field

The utility model relates to a pressure regulating device for natural gas entering a network.

Background

The natural gas is changed along with the downstream gas consumption, the natural gas pressure in the natural gas pipeline also fluctuates, the phenomenon of pipe vibration or air hammer occurs, the phenomenon brings adverse effects to pipe network parts such as valves, sensors, flowmeters and the like, and certain potential safety hazards also exist.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a natural gas pressure regulating device, which is used for solving the problem that adverse effects are brought to pipe network parts due to natural gas pressure unbalance.

In order to solve the problems, the technical scheme of the utility model is as follows:

the pressure regulating device of the natural gas of the network, including the natural gas admission line, the intercommunication has odorizing device, export atmospheric valve, chromatography to take over and flowmeter on the admission line, the intercommunication has two PID valves on the admission line, the admission line communicates with the gas energy storage ware through first branch pipe between two PID valves, all communicate at PID valve both ends has pressure sensor, each pressure sensor connection controller input, PID valve connection control output.

One end of an air inlet pipeline between the two PID valves is communicated with the nitrogen accumulator through a second branch pipe, the other end of the air inlet pipeline between the two PID valves is communicated with a third branch pipe, a first electric valve, a second electric valve and a third electric valve are respectively arranged on the first branch pipe, the second branch pipe and the third branch pipe, and the first electric valve, the second electric valve and the third electric valve are connected with the output end of the controller.

The nitrogen accumulator is communicated with the nitrogen source through a fourth branch pipe, a fourth electric valve and an air pump are installed on the fourth branch pipe, the fourth electric valve and the air pump are connected with the output end of the controller, and a pressure switch installed on the fourth branch pipe is connected with the output end of the controller.

The utility model has the beneficial effects that: carry out the export after the secondary decompression to the natural gas of advancing of carrying the pipe network through two PID valves, set up the energy storage ware simultaneously between two PID valves and carry out the steady voltage to the natural gas of advancing the net, make a buffer area between natural gas pressure of advancing the net and the natural gas station atmospheric pressure, and then maintain the natural gas pipe network pressure of advancing the net invariable, avoid appearing vibrating tube and air hammer phenomenon, the life of pipe network parts such as extension valve, sensor and flowmeter, improve flowmeter measurement accuracy simultaneously.

Drawings

The utility model is further described below with reference to the accompanying drawings:

figure 1 is a schematic structural view of the present invention,

fig. 2 is a schematic diagram of the connection relationship between the electrical components used in the present invention.

In the figure: the device comprises a natural gas inlet pipeline 1, an odorizing device 2, a flowmeter 3, a first pressure sensor 4, a first PID valve 5, a second pressure sensor 6, a first branch pipe 7, a first electric valve 8, a gas accumulator 9, a third electric valve 10, a third branch pipe 11, a second PID valve 12, a third pressure sensor 13, a second branch pipe 14, a second electric valve 15, a nitrogen accumulator 16, a pressure switch 17, a fourth branch pipe 18, a fourth electric valve 19 and an air pump 20.

Detailed Description

As shown in figures 1 and 2, the pressure regulating device for the natural gas of the network inlet comprises a natural gas inlet pipeline 1, an odorizing device 2, an outlet vent valve, a chromatographic analysis connecting pipe and a flowmeter 3 are communicated on the inlet pipeline 1, two PID valves are communicated on the inlet pipeline 1, the inlet pipeline 1 between the two PID valves is communicated with a gas accumulator 9 through a first branch pipe 7, pressure sensors are communicated at two ends of the PID valves, each pressure sensor is connected with the input end of a controller, for example, three pressure sensors are arranged in figure 1, the three pressure sensors are respectively a first pressure sensor 4, a second pressure sensor 6 and a third pressure sensor 13, the two PID valves are respectively a first PID valve 5 and a second PID valve 12, the two PID valves are connected with the control output end, the controller is a PLC controller, and a PID module in the PLC controller is electrically connected with the two PID valves, the controller adjusts the output value of the PID module to be 0% -100% according to the change rate of the pressure signal transmitted by each pressure sensor, and adjusts the current of the two PID valves to be 4-20 mA according to the PID output value so as to control the opening degree of the PID valves.

In implementation, if the natural gas consumption is increased in the weather, the first pressure sensor 4 detects the pressure drop of the natural gas entering the network, at this time, the controller controls the first PID valve 5 to increase the opening degree, so that the natural gas in the gas accumulator 9 is rapidly supplemented to the gas inlet pipeline 1, the gas pressure drop of the natural gas entering the network is compensated, until the first pressure sensor 4 detects the pressure recovery set pressure, because the opening degree of the first PID valve 5 is increased, the second pressure sensor 6 detects the pressure drop of the gas inlet pipeline 1 between the two PID valves, at this time, the controller controls the second PID valve 12 to increase the opening degree, the natural gas pressure in the gas inlet pipeline 1 between the two PID valves 12 recovers the set pressure, if the natural gas consumption is reduced, the controller controls the first PID valve 5 to reduce the opening degree, the natural gas entering the network is subjected to secondary pressure reduction through the two PID valves and then is delivered, the influence of a natural gas station on the natural gas entering the network is reduced, the pressure of the natural gas entering the network can be kept constant, and the phenomena of a vibrating pipe and an air hammer are avoided.

One end of an air inlet pipeline 1 between the two PID valves is communicated with a nitrogen accumulator 16 through a second branch pipe 14, the other end of the air inlet pipeline 1 between the two PID valves is communicated with a third branch pipe 11, a first electric valve 8, a second electric valve 15 and a third electric valve 10 are respectively installed on the first branch pipe 7, the second branch pipe 14 and the third branch pipe 11, and the first electric valve 8, the second electric valve 15 and the third electric valve 10 are connected with the output end of a controller.

When the emergency shutdown is needed, the two PID valves are cut off emergently, the first electric valve 8 is closed at the same time, the second electric valve 15 and the third electric valve 10 are opened, nitrogen enters the air inlet pipeline 1 between the two PID valves, natural gas in the air inlet pipeline 1 between the two PID valves is emptied, so that an isolation zone is formed between the net inlet natural gas and the natural gas station, nitrogen is filled for protection, and the pipeline explosion is prevented.

The nitrogen accumulator 16 is communicated with a nitrogen source through a fourth branch pipe 18, a fourth electric valve 19 and an air pump 20 are installed on the fourth branch pipe 18, the fourth electric valve 19 and the air pump 20 are connected with the output end of the controller, and a pressure switch 17 installed on the fourth branch pipe 18 is connected with the output end of the controller. The nitrogen source is the cooled nitrogen of the LNG station, and the nitrogen is sent to the nitrogen accumulator 16 through the air pump 20 to be stored in a pressurized mode, so that the nitrogen accumulator 16 can be used repeatedly.

Claims

1. Pressure regulating device of natural gas of advancing net, including natural gas admission line (1), the intercommunication has odorization device (2), export atmospheric valve, chromatographic analysis takeover and flowmeter (3) on admission line (1), its characterized in that: two PID valves are communicated on the air inlet pipeline (1), the air inlet pipeline (1) between the two PID valves is communicated with the gas energy accumulator (9) through a first branch pipe (7), pressure sensors are communicated at two ends of the PID valves, each pressure sensor is connected with the input end of the controller, and the PID valves are connected with the control output end.

2. The pressure regulating device for the gas coming into the network according to claim 1, characterized in that: one end of an air inlet pipeline (1) between the two PID valves is communicated with a nitrogen energy accumulator (16) through a second branch pipe (14), the other end of the air inlet pipeline (1) between the two PID valves is communicated with a third branch pipe (11), a first electric valve (8), a second electric valve (15) and a third electric valve (10) are respectively installed on the first branch pipe (7), the second branch pipe (14) and the third branch pipe (11), and the first electric valve (8), the second electric valve (15) and the third electric valve (10) are connected with the output end of a controller.

3. The pressure regulating device for the gas entering the network according to claim 2, wherein: the nitrogen accumulator (16) is communicated with a nitrogen source through a fourth branch pipe (18), a fourth electric valve (19) and an air pump (20) are installed on the fourth branch pipe (18), the fourth electric valve (19) and the air pump (20) are connected with the output end of the controller, and a pressure switch (17) installed on the fourth branch pipe (18) is connected with the output end of the controller.