Outwards-leaked gate valve middle cavity overpressure protection device

Abstract

The invention discloses an outwards-leaked gate valve middle cavity overpressure protection device. The outwards-leaked gate valve middle cavity overpressure protection device comprises an inlet sidemain pipeline communicated with the inlet side of a double-gate-plate gate valve, the side portion of the inlet side main pipeline is provided with a valve front drainage pipeline in a communicated mode, and a drainage valve is arranged on the valve front drainage pipeline; and an overpressure protection system is arranged between the valve front drainage pipeline located on the downstream portionof the drainage valve and a middle cavity of the double-gate-plate gate valve in a communicating mode and is in interactive connection with a DCS controller used for receiving detection signals of the overpressure protection system and capable of controlling the overpressure protection system to operate. According to the outwards-leaked gate valve middle cavity overpressure protection device, itis effectively guaranteed that the double-gate-plate gate valve is not prone to being damaged through the valve front drainage pipeline arranged at the bottom of the inlet side main pipeline in a communicating mode, and the overpressure protection system is arranged between the middle cavity of the double-gate-plate gate valve and the valve front drainage pipeline, so that the pressure of the middle cavity of the double-gate-plate gate valve can be monitored, the purpose of automatic relief of overpressure of the middle cavity of the double-gate-plate gate valve is achieved, and it is guaranteed that double gate plates have the double-sealing effect.

Description

technical field

[0001] The invention relates to the technical field of overpressure protection for a double-disc gate valve, and more particularly relates to an overpressure protection device for a cavity of a gate valve with external discharge. Background technique

[0002] Double disc gate valve, the double disc fits the valve seats on both sides, has the advantages of simple structure, reliable sealing performance, good sealing performance, small opening and closing torque, long service life, etc. It is widely used in electric power, oil, natural gas, chemical and other pipelines system. It is precisely because of its excellent sealing structure on both sides that in some cases, the pressure in the cavity of the gate valve will rise abnormally. Usually the fluid medium of the system changes from a cold state to a hot state after starting up, and the gate valve of the main pipeline is closed in the cold state, and the main gate valve can only be opened when the main pipel...

Examples

Embodiment 1

[0024] An overpressure protection device for the inner cavity of a gate valve with external discharge, combined with figure 1 As shown, it includes the main pipeline 1 at the inlet side, the drain pipeline 9 before the valve, the steam trap 3, the overpressure protection system and the DCS controller.

[0025] The main pipeline 1 on the inlet side communicates with the inlet side of the double gate valve 2, and is used for conveying high-temperature and high-pressure fluid.

[0026] The drain pipe 9 before the valve is connected to the bottom of the main pipe 1 on the inlet side, and is used to fully drain water when the system is started, so as to prevent the accumulation of water in the main pipe 1 on the inlet side.

[0027] The drain valve 3 is arranged on the drain pipe 9 in front of the valve, and is used to control the opening and closing of the drain pipe 9 in front of the valve.

[0028] The overpressure protection system is connected between the drain pipe 9 located...

Embodiment 2

[0040] Based on the basis of Embodiment 1, the difference between this embodiment and Embodiment 1 is that a manual external pressure relief overpressure protection system is also connected between the main pipe 7 of the external discharge pipeline and the drain pipe 9 before the valve. The pressure and overpressure protection system is used for manual operation when the automatic external pressure relief and overpressure protection system fails, so as to discharge the fluid in the cavity of the double gate valve into the drain pipe 9 in front of the valve. The manual external pressure relief and overpressure protection system is the manual pressure relief redundant system, which is set in parallel with the automatic external pressure relief and overpressure protection system.

[0041] The manual external pressure relief overpressure protection system includes a manual external discharge pipeline 8 connected between the main pipe 7 of the external discharge pipeline and the dra...

technical field

[0001] The invention relates to the technical field of overpressure protection for a double-disc gate valve, and more particularly relates to an overpressure protection device for a cavity of a gate valve with external discharge. Background technique

[0002] Double disc gate valve, the double disc fits the valve seats on both sides, has the advantages of simple structure, reliable sealing performance, good sealing performance, small opening and closing torque, long service life, etc. It is widely used in electric power, oil, natural gas, chemical and other pipelines system. It is precisely because of its excellent sealing structure on both sides that in some cases, the pressure in the cavity of the gate valve will rise abnormally. Usually the fluid medium of the system changes from a cold state to a hot state after starting up, and the gate valve of the main pipeline is closed in the cold state, and the main gate valve can only be opened when the main pipel...

Examples

Embodiment 1

[0024] An overpressure protection device for the inner cavity of a gate valve with external discharge, combined with figure 1 As shown, it includes the main pipeline 1 at the inlet side, the drain pipeline 9 before the valve, the steam trap 3, the overpressure protection system and the DCS controller.

[0025] The main pipeline 1 on the inlet side communicates with the inlet side of the double gate valve 2, and is used for conveying high-temperature and high-pressure fluid.

[0026] The drain pipe 9 before the valve is connected to the bottom of the main pipe 1 on the inlet side, and is used to fully drain water when the system is started, so as to prevent the accumulation of water in the main pipe 1 on the inlet side.

[0027] The drain valve 3 is arranged on the drain pipe 9 in front of the valve, and is used to control the opening and closing of the drain pipe 9 in front of the valve.

[0028] The overpressure protection system is connected between the drain pipe 9 located...

Embodiment 2

[0040] Based on the basis of Embodiment 1, the difference between this embodiment and Embodiment 1 is that a manual external pressure relief overpressure protection system is also connected between the main pipe 7 of the external discharge pipeline and the drain pipe 9 before the valve. The pressure and overpressure protection system is used for manual operation when the automatic external pressure relief and overpressure protection system fails, so as to discharge the fluid in the cavity of the double gate valve into the drain pipe 9 in front of the valve. The manual external pressure relief and overpressure protection system is the manual pressure relief redundant system, which is set in parallel with the automatic external pressure relief and overpressure protection system.

[0041] The manual external pressure relief overpressure protection system includes a manual external discharge pipeline 8 connected between the main pipe 7 of the external discharge pipeline and the dra...

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