JPH0914189A - Delivery check valve - Google Patents

Abstract

PURPOSE: To perform the stable restarting of a fluid machine without continuing operation in a surging state by providing a closing preventing pipe to intercommunicate a delivery parent pipe and the part, situated downstream, of the suction sluice valve of a suction pipe, and a partition valve mounted in the closing preventing pipe, in a delivery check valve mounted in the delivery pipe of a fluid machine. CONSTITUTION: A blower for feeding city gas has a plurality of blowers arranged between a suction parent pipe 1 and a delivery parent pipe 2, and the suction port of each blower 3 is connected to a suction pipe 4 in which a suction sluice valve 5 is located. The delivery port of each blower 3 is connected to a delivery pipe 6 in which a delivery check valve 7 and a delivery sluice valve 8 are located. In this case, a closing preventing pipe 10 running from the delivery parent pipe 2 and communicated to the part, situated downstream, of the suction sluice valve 5 is disposed, and a sluice valve 11 is also located in the closing preventing pipe 10. When the blower 3 under a stop is restarted during operation of the blower 3, the slice valve 11 is opened and a pressure in the blower 3 under a stop is adjusted to a value equal to a pressure in the delivery parent pipe 2. When the pressures are adjusted to respective values equal to each other, the blower 3 under a stop is restarted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge check valve applied to a blower in which a plurality of units are arranged in parallel.

[0002]

2. Description of the Related Art FIG. 2 is an explanatory view of a conventional discharge check valve used in a blower in which a plurality of units are arranged in parallel. In the figure, a blower for supplying city gas in a gas company and a blower for supplying coke oven gas in a steel mill have the same shape and 3 to 4 blowers of the same capacity are arranged in parallel, so as to respond to changes in demand. In addition to making it possible, it facilitates maintenance. That is, a plurality of blowers 3 are arranged in parallel between the suction mother pipe 1 and the discharge mother pipe 2, and the suction port of each blower 3 is connected to a suction pipe 4 branched from the suction mother pipe 1. There is. The suction pipe 4 is provided with a suction gate valve 5, a pressure gauge 9, and the like. The discharge port of each blower 3 is connected to the discharge pipe 6, and the discharge pipe 6 is connected to the discharge mother pipe 2. The discharge pipe 6 is provided with a discharge check valve 7, a discharge sluice valve 8, a pressure gauge 9, and the like. Generally, the diameter of the discharge check valve 7 is large,
In the case of medium diameter, swing type is often used.

[0003]

In the conventional discharge check valve as described above, any one of the blowers 3 having the same shape and the same capacity and arranged in parallel is restarted. In this case, since the discharge pressure of the blower 3 in another operation is applied to the discharge check valve 7 of the stopped blower 3 from the discharge mother pipe 2 side, the discharge check valve 7 cannot swing and is blocked. May remain. When the blower 3 is operated in the closed state as described above, the blower 3 is continuously operated in the surging state until the discharge pressure is in equilibrium with the pressure in the discharge mother pipe 2, the temperature rises, and vibration occurs,
Eventually, it may cause contact accidents. Further, since the blower 3 is in the surging state, the performance is in a turbulent range, and in some cases, the discharge pressure may not equilibrate with the pressure in the discharge mother pipe 2 and the discharge check valve 7 may not open forever. .

[0004]

A discharge check valve according to the present invention is intended to solve the above-mentioned problems. A suction check valve in which a plurality of units are connected in parallel to a common discharge mother pipe and equipped with a suction check valve is provided. In a discharge check valve mounted on a discharge pipe of a fluid machine that sucks and pressurizes and discharges a fluid through a pipe, a blocking prevention pipe that communicates the discharge mother pipe with the suction gate valve downstream of the suction pipe, And a sluice valve attached to the blockage prevention pipe.

[0005]

In other words, in the discharge check valve according to the present invention, a plurality of units are connected in parallel to a common discharge mother pipe and a fluid is sucked and pressurized through a suction pipe equipped with a suction check valve to discharge the fluid. Other fluids that are connected in parallel with the sluice valve installed in the blockage prevention pipe that connects the discharge mother pipe of the discharge check valve installed in the discharge pipe of the fluid machine and the suction sluice valve downstream of the suction pipe. When restarting a fluid machine that is stopped while the machine is running, keep the suction sluice valve of the stopped fluid machine fully closed and the discharge sluice valve appropriately open, and open the check valve of the blockage prevention pipe. The fluid machine to the same pressure as the discharge mother tube. After doing this, by starting the fluid machine with the suction sluice valve fully closed, the discharge pressure becomes higher than the pressure in the discharge mother pipe by the amount of work done by the fluid machine, and the discharge check valve opens. Starts to stand up. Then, the suction sluice valve is gradually opened and the sluice valve of the blockage prevention pipe is gradually closed. In this way, the discharge check valves are prevented from being closed when the fluid machines installed in parallel are restarted.

[0006]

1 is an explanatory view of a discharge check valve according to an embodiment of the present invention. In the figure, the discharge check valve according to the present embodiment is used for a blower in which a plurality of units are arranged in parallel, such as a blower for supplying city gas in a gas company or a blower for supplying coke oven gas in a steel mill. Has three to four blowers of the same shape and capacity, which are arranged in parallel, which makes it possible to respond to changes in demand and facilitate maintenance. That is, a plurality of blowers 3 are arranged in parallel between the suction mother pipe 1 and the discharge mother pipe 2, and the suction port of each blower 3 is connected to a suction pipe 4 branched from the suction mother pipe 1. There is. The suction pipe 4 is provided with a suction gate valve 5, a pressure gauge 9, and the like. The discharge port of each blower 3 is connected to the discharge pipe 6, and the discharge pipe 6 is connected to the discharge mother pipe 2. The discharge pipe 6 is provided with a discharge check valve 7, a discharge sluice valve 8, a pressure gauge 9, and the like.

The discharge check valve 7 according to the present embodiment includes:
The suction sluice valve 5 of the suction pipe 4 is branched from the discharge mother pipe 2 so that the blower 3 stopped can be smoothly and safely restarted while the other blower 3 connected in parallel is operating.
A blockage prevention pipe 10 of the discharge check valve 7 that communicates with the downstream side is provided. The blocking valve 11 is also provided with a sluice valve 11. The blockage prevention tube 10 does not have to have the same diameter as the discharge tube, and may be a small diameter tube as long as it is suitable for the rising time.

When the blower 3 stopped while the other blower 3 is in operation is restarted, the suction sluice valve 5 of the stopped blower 3 is fully closed and the discharge sluice valve 8 is opened appropriately. To do. Then, the sluice valve 11 of the blocking prevention pipe 10 is opened to make the inside of the blower 3 being stopped the same pressure as the inside of the discharge mother pipe 2. When the pressure in the blower 3 becomes equal to the pressure in the discharge mother pipe 2, the stopped blower 3 is restarted with the suction sluice valve 7 fully closed. Then, the discharge pressure of the blower 3 increases by the amount of work of the restarted blower 3 and becomes higher than the pressure in the discharge mother pipe 2, and the discharge check valve 7 is opened to start operating. At this time, the load of the blower 3 is adjusted by reducing the opening of the discharge sluice valve 8 so that the restarted blower 3 is not overloaded. After that, the suction sluice valve 5 is gradually opened and the sluice valve 11 of the blocking prevention pipe 10 is gradually closed. By operating each valve in this way, a smooth and safe start-up operation of the blower 3 that is stopped can be performed.

In the conventional discharge check valve, if one of the blowers arranged in parallel with the same shape and the same capacity is stopped and restarted, the discharge of the other operating blower is attempted. Since the pressure is applied to the discharge check valve of the stopped blower from the discharge mother pipe side, the discharge check valve may not swing and may remain in a closed state. When the blower is operated in this closed state, the blower continues to operate in the surging state until the discharge pressure is in equilibrium with the pressure in the discharge mother pipe, the temperature rises, and vibration occurs,
Eventually, it may cause contact accidents. Also, because the blower is in a surging state, the performance is in a turbulent range,
In some cases, the discharge pressure may not equilibrate with the pressure in the discharge mother pipe, and the discharge check valve may not open indefinitely. 2 is provided with a blocking valve 10 for the discharge check valve 7 which branches from 2 and communicates with the downstream of the suction sluice valve 5 of the suction pipe 4, and a sluice valve 11 is provided on the blocking valve 10 for the other blower 3 When restarting the blower 3 which is stopped during the operation of 1, the sluice valve 11 of the blockage prevention pipe 10 is opened to make the inside of the blower 3 at the same pressure as the discharge mother pipe 2 and then the blower 3 is closed. By restarting, the discharge check valve 7 opens reliably, and it is possible to remove the cause of vibration such as continuing the operation of the restarted blower 3 in the surging state, and to start the blower 3 smoothly and stably. It will be possible.

[0010]

The discharge check valve according to the present invention is constructed as described above, and the discharge check valve is prevented from being closed when the fluid machines installed in parallel are restarted. It enables a stable restart of the fluid machine without continuing operation.

[Brief description of the drawings]

FIG. 1 is a flow system diagram of a discharge check valve according to an embodiment of the present invention.

FIG. 2 is a flow system diagram of a conventional discharge check valve.

[Explanation of symbols]

 1 Suction mother pipe 2 Discharge mother pipe 3 Blower 4 Suction pipe 5 Suction gate valve 6 Discharge pipe 7 Discharge check valve 8 Discharge sluice valve 9 Pressure gauge 10 Discharge check valve blockage prevention pipe 11 Blockage prevention pipe sluice valve

Claims (1)

[Claims] 1. A discharge reverse mounted on a discharge pipe of a fluid machine for sucking and pressurizing and discharging a fluid through a suction pipe having a plurality of units connected in parallel to a common discharge mother pipe and equipped with a suction check valve. A stop valve, comprising: a blockage prevention pipe communicating the discharge mother pipe and a downstream side of the suction gate valve of the suction pipe, and a gate valve attached to the blockage prevention pipe. .