KR100985763B1 - Pilot operated safety valve and operating method - Google Patents

Abstract

PURPOSE: A pilot operated safety valve and an opening and closing method thereof are provided to improve reliability of the safety valve by improving operation accuracy. CONSTITUTION: A pilot operated safety valve comprises a main chamber(100), a main opening and closing valve(200), an auxiliary chamber(300), an auxiliary opening and closing valve(400), and an elastic unit(500). The main chamber has first and second chambers(110,120). The first and second chambers are divided by a first diaphragm(130). The main opening and closing valve is connected to the first diaphragm and opens and closes a gas inlet(1a) of a gas tank(1). The auxiliary chamber has third and fourth chambers(310,320) divided by a second diaphragm(330). The auxiliary opening and closing valve is connected to the second diaphragm. The elastic unit supports the auxiliary opening and closing valve.

Description

Pilot operated safety valve and operating method

The present invention relates to a pilot type safety valve and its opening and closing method.

More specifically, the present invention relates to a pilot type safety valve and a method of opening and closing the valve, which improves accuracy and reliability of valve opening and closing.

The safety valve is mounted on the pressure vessel or the upper part of the vacuum tank or the connecting pipe to maintain the proper pressure inside the pressure device.The pressure inside the device is regulated. Pressure) If it rises above or falls below the specified pressure, it automatically operates to maintain air tightness after the pressure drop or rise within the specified pressure range.

1 and 2 show an example of a conventional safety valve.

The conventional safety valve shown in FIG. 1 includes a main valve part 10 mounted to a storage tank, and a pilot valve part 20 installed above the main valve part 10 to assist the operation of the main valve part. The pilot valve part 20 is operated under pressure first, and then the main valve part 10 is operated.

First, the main valve part 10 is provided with a main inlet port 11a connected to a storage tank (not shown), and a main outlet port 11b connected to a discharge pipe (not shown). The main inlet port 11a is provided. And a main valve housing 11 having a main valve chamber 11c formed between the main discharge port 11b and the main discharge port 11b.

In addition, the main valve 12 is provided in the main valve chamber (11c) to be lifted, the main valve seat 13 is installed on the main inlet port (11a) is seated.

The pilot valve part 20 includes a pilot body 21 and a pilot valve 22 coupled to the pilot body 21.

A pressure chamber 21a is formed inside the pilot body 21, and a pilot valve seat 21b is installed inside the pressure chamber 21a to selectively mount a plunger 22c to be described later. One side of the pressure chamber 21a below the valve seat 21b is formed with a pilot inlet port 21c connected to the main inlet port 11a and the bypass pipe 30, and is located above the pilot valve seat 21b. On the other side of the pressure chamber 21a of the pilot connection port 21d which is connected to the upper side of the main valve 12 and the connection pipe 40 is formed, the outside of the pilot connection port 21d The pilot discharge port 21e is formed in communication with.

The pilot valve 22 includes a pilot valve housing 22a, a return spring 22b embedded in the pilot valve housing 22a, and a return spring 22b below the pilot valve housing 22a. And a plunger 22c installed to be elastically supported by the plunger 22c and an opening and closing stopper 22d that is installed outside the plunger so as to be interlocked with the plunger 22c to selectively open and close the pilot discharge port 21e. .

In the conventional safety valve having such a configuration, when an overpressure greater than the prescribed pressure is applied to the main inlet port 11a, the main valve 12 is forcibly raised by the overpressure as shown in FIG. Since the discharge port 11b communicates, the overpressure is discharged through the main discharge port 11b.

In addition, a part of the overpressure enters the pilot body 21 through the bypass pipe 30 and the pilot inlet port 21c to forcibly push up the plunger 22c lowered by the return spring 22b. The bypass tube 30 and the pressure chamber 21a are in communication.

Therefore, the overpressure entering through the bypass pipe 30 is partially discharged to the pilot discharge port 21e, and the other part is entered into the main valve 12 through the pilot connection port 21d and the connection pipe 40. . However, since the overpressure entering the main valve 12 is smaller than the overpressure discharged from the main inlet port 11a, the main valve 12 is still maintained in an elevated state.

From this state, when the overpressure flowing from the main inlet port 11a is weakened (that is, the normal pressure is at the pressure of the main inlet port), as shown in FIG. 2, the plunger ( 22c) is lowered.

Then, the pilot discharge port 21e is blocked by the opening and closing plug 22d, and the bypass pipe 30 is blocked by the plunger 22c, respectively. In addition, the main valve 12 is pushed down by the air pressure remaining in the connecting pipe 40, the main valve 12 is lowered in the drawing, thereby the main inlet port (11a) by the main valve 12 It will be restored to its original state that it was blocked.

However, in the conventional safety valve described above, the lowering operation of the main valve 12 is operated by the internal pressure in the connecting pipe 40, but the internal pressure in the connecting pipe 40 is set to the outlet pressure of the main inlet port 11a. If the comparison is small, the main valve 12 may not be completely lowered, so the reliability of the airtightness of the main inlet port 11a cannot be guaranteed.

In addition, when overpressure is applied to the main inlet port 11a, the main valve 12 should be lifted by the overpressure, but the main valve 12 is lifted depending on the magnitude of the internal pressure of the connecting pipe 40. If it does not occur, it may not work on time even if it is lifted, it can be operated late, which slows down the reliability of the product due to the problem of slow response.

Accordingly, the present invention has been proposed to solve the conventional problems as described above, the main object of the present invention is a pilot-type safety that can improve the reliability of the product by quickly responsive to the valve drive and increase the accuracy of opening and closing In providing a valve.

According to the main aspect of the present invention for achieving the above object,

Pilot type safety valve installed on the gas tank,

The pilot type safety valve,

The first diaphragm includes a first chamber into which air is introduced into the atmosphere or the gas tank, and a second chamber into which gas enters when the air enters the first chamber, and when gas enters the first chamber. A main chamber partitioned by; A main on-off valve which opens and closes the gas inlet while interlocking with the first diaphragm; An auxiliary chamber in which a third chamber into which air is introduced and a fourth chamber into which gas is introduced are defined by a second diaphragm; An auxiliary on / off valve which opens and closes a connection flow path between the first chamber and the fourth chamber while interlocking with the second diaphragm; It is a pilot type safety valve consisting of; an elastic unit for elastically supporting the auxiliary on-off valve.

In addition, according to another main aspect of the present invention for achieving the above object,

A main chamber partitioned into a first chamber and a second chamber by a first diaphragm, an auxiliary chamber partitioned into a third chamber and a fourth chamber by a second diaphragm, and a gas inlet while interlocking with the first diaphragm Pilot type safety having a main on-off valve for opening and closing the opening, an auxiliary on-off valve for selectively opening between the first chamber and the fourth chamber while interlocking with the second diaphragm, and an elastic unit for elastically supporting the auxiliary on-off valve With a valve,

When the internal pressure of the gas tank is within the prescribed pressure, air is introduced into the second chamber and the third chamber, and the first chamber and the fourth chamber are opened by the auxiliary on / off valve by the elastic force of the elastic unit. Allowing the gas in the gas tank to flow in such that the first diaphragm and the main on-off valve flow by the differential pressure of the first chamber and the second chamber to automatically shut off the gas inlet; When the internal pressure of the gas tank is equal to or higher than the prescribed pressure, the overpressure gas from the gas tank flows into the second chamber and the fourth chamber, so that the first diaphragm and the main opening / closing valve are differential pressure between the second chamber and the fourth chamber. It is a method of opening and closing the pilot type safety valve to flow by to open the gas inlet automatically.

The pilot type safety valve according to the present invention can improve the reliability of the product by speeding up the response of the valve drive and increasing the accuracy of the operation.

Advantages and features of the present invention, and methods of achieving them will become more apparent with reference to the embodiments described below in conjunction with the accompanying drawings.

3 is a pilot type safety valve according to the present invention, in which a gas inlet is blocked; Figure 4 is a pilot type safety valve according to the present invention, the gas inlet is open state.

Pilot type safety valve of the present invention according to the above drawings is installed on the gas inlet (1a) upper portion of the gas tank (1) when the gas tank (1) is normal pressure close the gas inlet (1a), the gas tank (1) When the overpressure is a safety device for preventing the overpressure damage of the gas tank (1) by opening the gas inlet (1a) to discharge the gas pressure as much as the overpressure component through the discharge flow path (800).

The pilot type safety valve of the present invention includes a main chamber 100, a main open / close valve 200, an auxiliary chamber 300, an auxiliary open / close valve 400, and an elastic unit 500.

For reference, the auxiliary chamber 300, the auxiliary open / close valve 400, the elastic unit 500, etc. serve as an auxiliary valve for operating the main chamber 100 and the main open / close valve 200 as a pilot valve. Also called a pilot valve.

First, the main chamber 100 is configured such that the first chamber 110 and the second chamber 120 are partitioned by the first diaphragm 130 in the up and down directions.

Here, the gas discharged from the atmosphere or the gas tank 1 is selectively introduced into the first chamber 110, and the atmosphere or gas is selectively introduced into the second chamber 120, but the first chamber ( A fluid opposite to the fluid introduced into 110 is introduced. That is, when air flows into the first chamber 110, gas flows into the second chamber 120, and when gas flows into the first chamber 110, the air flows into the second chamber 120.

When the gas flows into one of the first and second chambers 110 and 120 and the atmosphere flows into the other, the first diaphragm 130 is autonomously displaced toward the low pressure chamber by the differential pressure between the gas and the atmosphere.

The main on-off valve 200 is coupled to the first diaphragm 130 is interlocked in the up, down direction in accordance with the displacement of the first diaphragm 130.

The main opening / closing valve 200 is installed to pass through the bottom of the main chamber 100 while being provided at the coupling portion 210 coupled to the first diaphragm 130 and the lower portion of the coupling portion 210. It is composed of a stem portion 220 and the opening and closing portion 230 which is provided in the lower portion of the stem portion 220 to open and close the gas inlet (1a).

In the auxiliary chamber 300, the third chamber 310 and the fourth chamber 320 are partitioned by the second diaphragm 330 in the up and down directions.

Here, the third chamber 310 is in communication with the outside through the atmospheric port 311 and is always at atmospheric pressure, and gas is introduced into the fourth chamber 320. In addition, the fourth chamber 320 is connected to the first chamber 110 by a connection passage 340.

The amount of displacement toward the third chamber 310 is determined by how much gas is introduced into the fourth chamber 320 of the second diaphragm 330. That is, when a small amount of gas flows into the fourth chamber 320, the displacement amount into the third chamber 310 will be small. If a large amount of gas flows into the fourth chamber 320, the displacement amount into the third chamber 310 becomes large.

The auxiliary on-off valve 400 is coupled to the second diaphragm 330 and is interlocked in the up and down directions in accordance with the displacement of the second diaphragm 330.

The auxiliary on / off valve 400 is installed through the coupling part 410 coupled to the second diaphragm 330 and the bottom of the auxiliary chamber 300 while being provided under the coupling part 410. The stem portion 420 and the opening and closing portion 430 provided at the lower portion of the stem portion 420 to open and close the connection passage 340.

In addition, a coupling portion 440 for connecting to the elastic unit 500 is provided above the coupling portion 410 of the auxiliary opening / closing valve 400, and below the coupling portion 440 of the auxiliary opening / closing valve 400. A stopper 450 is formed on the upper surface of the auxiliary chamber 300 to limit the rising range.

The elastic unit 500 is installed in the elastic case 510 and the elastic case 510 is installed on the upper side of the auxiliary chamber 300, one side is supported by the elastic case 510 and the other side is the auxiliary It is composed of an elastic body 520 supported by the connecting portion 440 of the on-off valve 400.

Here, the elastic body 520 supports the auxiliary on / off valve 400, and supports the auxiliary on / off valve 400 in an open direction.

Hereinafter, the connection relationship between the main chamber 100 and the auxiliary chamber 300 will be described.

First, the gas inlet 1a and the fourth chamber 320 are connected by the first pipeline 610. The first pipeline 610 serves to allow the gas flowing out of the gas inlet 1a to flow into the fourth chamber 320.

Here, the first auxiliary pipe line 620 may be further configured to be branched from the first pipeline 610 and connected to the connection passage 340 together with the first pipeline 610. .

In addition, the second chamber 120 and the third chamber 310 are connected by a second pipeline 630. The second pipeline 630 serves to allow the atmosphere in the third chamber 310 to flow into the second chamber 120 when the auxiliary on / off valve 400 is lowered.

In addition, the second chamber 120 and the fourth chamber 320 are connected by a third pipeline 640. The third pipeline 640 allows the gas in the fourth chamber 320 to flow into the second chamber 120 when the gas inlet 1a is opened when the auxiliary on / off valve 400 is raised. Do it.

On the other hand, the opening port 111 provided on the upper side of the first chamber 110 is opened and closed by the port opening and closing valve 710 in conjunction with the main opening and closing valve 200. That is, when the main on-off valve 200 rises, the port on-off valve 710 also rises to open the opening port 111, so that atmospheric air flows in, and when the main on-off valve 200 descends, the on-off valve 710 is also lowered. As it descends, the opening port 111 is closed to block the inflow of air.

In addition, the third chamber 310 side of the second pipeline 630 and the fourth chamber 320 side of the third pipeline 640 are connected to the auxiliary on-off valve 400 line on-off valve ( By 720).

Hereinafter will be described the opening and closing process (opening and closing method) of the pilot type safety valve according to the present invention.

First, when the internal pressure of the gas tank 1 is within the prescribed pressure, some gas in the gas tank flows into the fourth chamber 320 by the first pipeline 610.

At this time, since the pressure of the gas flowing into the fourth chamber 320 is not a high pressure, it is smaller than the elastic force of the elastic body 520.

Therefore, the auxiliary opening / closing valve 400 installed in the auxiliary chamber 300 is lowered by being controlled by the elastic force of the elastic body 520, and in this state, between the fourth chamber 320 and the first chamber 110. Since the connection passage 340 connecting the gas is in an open state, gas in the fourth chamber 320 is introduced into the first chamber 110 through the connection passage 340.

On the other hand, the air flows into the third chamber 310 through the air port 311, and the line on / off valve 720 is lowered together with the auxiliary auxiliary on / off valve 400 that is lowered. The third chamber 310 side of the opening is in an open state, thereby allowing the atmosphere of the third chamber 310 to flow into the second chamber 120.

In other words, the third chamber 310 and the second chamber 120 are at atmospheric pressure, and the fourth chamber 320 and the first chamber 110 are at a gas pressure. In particular, since the internal pressure of the first chamber 110 is greater than the internal pressure of the second chamber 120 (the gas pressure is greater than atmospheric pressure), the first diaphragm 130 moves downward in the drawing. The main inlet valve 200 is also lowered by the main on / off valve 200, which is displaced and interlocked with the gas inlet 1a.

In addition, the third pipeline 640 connecting the fourth chamber 320 and the second chamber 120 may be connected to the fourth chamber 320 by a line on / off valve 720 interlocking with the auxiliary on / off valve 400. Since the side 320 is in a blocked state, gas of the fourth chamber 320 is not introduced into the second chamber 120.

On the other hand, when the internal pressure of the gas tank 1 is greater than or equal to the prescribed pressure, some gas in the gas tank is introduced into the fourth chamber 320 by the first pipeline 610.

At this time, the pressure of the gas flowing into the fourth chamber 320 is greater than the elastic force of the elastic body 520 because it is an overpressure state.

Therefore, the auxiliary opening / closing valve 400 installed in the auxiliary chamber 300 rises together with the second diaphragm 330 while overcoming the elastic force of the elastic body 520 due to the increase in the internal pressure of the fourth chamber 320. As the auxiliary on / off valve 400 is raised, the line on / off valve 720 is also raised and the third chamber 310 side of the second pipeline 630 is blocked and the connection flow path 340 is also blocked. do.

On the other hand, since the fourth chamber 320 side of the third pipeline 640 is opened due to the rise of the line opening / closing valve 720, the overpressure gas in the fourth chamber 320 opens the third pipeline 640. It is introduced into the second chamber 120 through.

Accordingly, since the internal pressure of the second chamber 120 is increased, the main on-off valve 200 is raised. In addition, as the main on-off valve 200 rises, the port on-off valve 710 coupled thereto also rises, and thus the atmosphere flows into the first chamber 110 to help the main on-off valve 200 to move up.

In summary, when the gas inlet 1a is opened due to the rise of the main on-off valve 200, the overpressure gas in the gas tank 1 is discharged through the discharge passage 800 to stabilize the pressure in the gas tank 1. It becomes possible.

When the discharge of the overpressure gas is stabilized through this process, it is switched to the initial state of blocking the gas inlet 1a described above.

The embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art having various ordinary knowledge of the present invention may make various modifications, changes, and additions within the spirit and scope of the present invention. Additions should be considered to be within the scope of the following claims.

1 is a longitudinal cross-sectional view of a conventional pilot type safety valve, an operating state diagram

Figure 2 is a longitudinal sectional view of a conventional pilot type safety valve, the initial state diagram

3 is a longitudinal sectional view of a pilot type safety valve according to the present invention, the initial state diagram

Figure 4 is a longitudinal cross-sectional view of the pilot type safety valve according to the present invention, the operation state diagram

<Explanation of symbols for the main parts of the drawings>

1: gas tank 1a: gas inlet

100: main chamber 110: first chamber

120: second chamber 130: first diaphragm

200: main opening and closing valve 300: auxiliary chamber

310: third chamber 320: fourth chamber

330: second diaphragm 340: connection euro

400: auxiliary closing valve 500: elastic unit

610: first pipeline 620: first auxiliary pipeline

630: second pipeline 640: third pipeline

710: port on-off valve 720: line on-off valve

800: discharge passage

Claims (4)

Pilot type safety valve installed on the top of the gas tank, The pilot type safety valve, The first diaphragm includes a first chamber into which air is introduced into the atmosphere or the gas tank, and a second chamber into which gas enters when the air enters the first chamber, and when gas enters the first chamber. A main chamber partitioned by; A main opening / closing valve which opens and closes a gas inlet of the gas tank while interlocking with the first diaphragm; An auxiliary chamber in which a third chamber into which air is introduced and a fourth chamber into which gas is introduced are defined by a second diaphragm; An auxiliary on / off valve which opens and closes a connection flow path between the first chamber and the fourth chamber while interlocking with the second diaphragm; Pilot type safety valve consisting of; an elastic unit for elastically supporting the auxiliary on-off valve. The method of claim 1, The gas inlet and the fourth chamber are connected by a first pipeline, the second chamber and the third chamber are connected by a second pipeline, and the second chamber and the fourth chamber are connected by a third pipeline. Connected, The opening port of the first chamber is opened and closed by a port opening / closing valve interlocked with the main opening / closing valve, and the third chamber side opening of the second pipeline and the fourth chamber side opening of the third pipeline are the auxiliary opening / closing valve. Pilot type safety valve that is opened and closed by a line on / off valve that is interlocked with. As installed in the upper part of the gas tank, A main chamber partitioned into a first chamber and a second chamber by a first diaphragm, an auxiliary chamber partitioned into a third chamber and a fourth chamber by a second diaphragm, and a gas inlet while interlocking with the first diaphragm Pilot type safety having a main on-off valve for opening and closing the opening, an auxiliary on-off valve for selectively opening between the first chamber and the fourth chamber while interlocking with the second diaphragm, and an elastic unit for elastically supporting the auxiliary on-off valve With a valve, When the internal pressure of the gas tank is within the prescribed pressure, air is introduced into the second chamber and the third chamber, and the first chamber and the fourth chamber are opened by the auxiliary on / off valve by the elastic force of the elastic unit. Allowing the gas in the gas tank to flow in such that the first diaphragm and the main on-off valve flow by the differential pressure of the first chamber and the second chamber to automatically shut off the gas inlet; When the internal pressure of the gas tank is equal to or higher than the prescribed pressure, the overpressure gas from the gas tank flows into the second chamber and the fourth chamber, so that the first diaphragm and the main opening / closing valve are differential pressure between the second chamber and the fourth chamber. Opening and closing method of the pilot type safety valve to flow by to open the gas inlet automatically. The method of claim 3, The gas inlet and the fourth chamber are connected by a first pipeline, the second chamber and the third chamber are connected by a second pipeline, and the second chamber and the fourth chamber are connected by a third pipeline. Connected, The opening port of the first chamber is opened and closed by a port opening / closing valve interlocked with the main opening / closing valve, and the third chamber side opening of the second pipeline and the fourth chamber side opening of the third pipeline are the auxiliary opening / closing valve. Opening and closing method of the pilot type safety valve is opened and closed by a line on-off valve interlocked with.

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