JPS6223200B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an improved fluid transport device.

[Conventional technology]

Conventionally, when fluid stored in a tank is continuously transported through a pipe, a device is generally used in which the tank and the main supply pipe are connected by a plurality of branch supply pipes arranged in parallel, each equipped with a pump. Ru. The above device stops some of the plurality of pumps as backup pumps, and when the pumps in operation are stopped due to failure or inspection, the backup pumps are started and continuously transported. be able to.

However, the above-mentioned device causes wide fluctuations in fluid pressure in the main supply pipe when switching pumps. That is, generally speaking, in pump switching work, in order to continuously transport fluid, first, a standby pump is started,
This is then carried out by stopping the target pump. Therefore, especially when the fluid is an incompressible fluid, when the backup pump is activated, the pressure in the branch supply pipe provided with the pump and the main supply pipe increases abnormally. Furthermore, when the target pump is stopped, the pressure in the main supply pipe drops rapidly.

Therefore, the above device cannot be used where it is required to transport fluid from a tank at constant pressure.

Therefore, various fluid transport devices have been proposed in the past for the purpose of improving the above-mentioned drawbacks. A typical device is shown in FIG. The transport device of FIG. 1 has a pressure regulating valve 5 in the main supply pipe 4 of the device.
The main supply pipe 4 and pressure control valve 5 are connected to a pressure detector 7 and a pressure regulator 8.
It is characterized by a structure connected through. In the above device, for example, when pump 2a is used as a backup pump and is switched to pump 2b which is in operation, pump 2a is first started. The pressure increase in the fluid in the main supply pipe due to activation of the pump 2a is detected by the pressure detector 7 and the detected pressure is converted into a signal. The signal is sent to the pressure regulator 8. A signal is sent to the pressure regulator to open the pressure regulating valve 5 so that the deviation between the pressure indicated by the signal and the preset pressure becomes zero. Thus, some of the fluid in the main supply pipe 4 is transferred to the withdrawal pipe 6.
The pressure of the fluid taken from the main supply pipe 4 and transported by the main supply pipe 4 is controlled. Then pump 2b
When the main supply pipe is stopped, the pressure of the fluid in the main supply pipe decreases, and as described above, a signal is sent via the pressure detector 7 and the pressure regulator 8, and the pressure regulating valve 5 is closed.
The pressure of the fluid transported by the main supply pipe 4 is thus controlled.

[Problem that the invention seeks to solve]

However, in the above-mentioned apparatus, rapid pressure fluctuations due to starting and stopping of the pump cannot be avoided, and even after the pressure regulating valve 5 starts operating, the pressure of the fluid in the main supply pipe 4 greatly hunts.

Therefore, when switching the pumps in the above device, when starting the pump 2a, the pump outlet stop valve 14a provided in the branch supply pipe 3a is throttled in advance to start the pump 2a, and the leaf pipe is connected via the relief valve 12a. circulating the fluid by 11a;
By gradually opening the pump outlet stop valve 14a, a sudden pressure increase due to activation of the pump 2a is prevented. Furthermore, when stopping the pump 2b, the pump outlet stop valve 14b provided on the branch supply pipe 3b is gradually throttled, the fluid is circulated through the relief pipe 11b provided with the relief valve 12b, and the pump 2b is stopped.
By stopping pump 2b, a sudden pressure drop due to stopping of pump 2b is prevented.

Although hunting in the fluid pressure in the main supply pipe at the time of pump switching can be suppressed to some extent by the above operation, hunting cannot be completely suppressed in the above device. In addition, it is necessary to operate the relief valve every time the pump is switched, and the relief valve is seriously damaged, which is economically disadvantageous.

[Means for solving problems]

The present invention improves the above-mentioned problems of conventional fluid transport devices, and makes it possible to completely prevent pressure fluctuations in the fluid in the main supply pipe when switching pumps during continuous fluid transport without causing any stress on the device. The present invention provides a transportation device.

That is, in the present invention, a tank and a main supply pipe are connected by a plurality of branch supply pipes arranged in parallel, and each branch supply pipe is provided with a pump and a check valve in order from upstream. A pressure detector and a pressure indicator are installed in each branch supply pipe and a take-out pipe having a pressure regulating valve is connected to the check valve, and a pressure detector is provided in the main supply pipe, The pressure detector is connected to the pressure regulating valve via a pressure regulator and an automatic/manual switch arranged in parallel corresponding to each of the plurality of pressure regulating valves. It is a transportation device.

In the present invention, tanks, pumps, pipe pressure regulating valves, pressure detectors, pressure regulators, automatic/manual switching devices, etc. that have known structures can be used without particular restriction.

〔Example〕

Hereinafter, the present invention will be described in detail using FIG. 2, which shows one embodiment of the fluid transport device of the present invention.

In FIG. 2, 1 is a tank and 4 is a main supply pipe. The tank 1 and the main supply pipe 4 are branch supply pipes 3a, 3 equipped with pumps 2a, 2b, 2c.
b, 3c are connected. Tank 1 and main supply pipe 4 with multiple branch supply pipes arranged in parallel
There is no particular restriction on the connection with the main supply pipe 4 as long as it is possible to independently send fluid from the tank 1 to the main supply pipe 4 using a pump provided on each branch supply pipe.

The branch supply pipes are provided with check valves 13a, 13b, 13c to prevent fluid from flowing back from the main supply pipe 4 into the branch supply pipes 3a, 3b, 3c when the pump is stopped or switched. The branch supply pipe also includes a pump inlet stop valve 10a,
10b, 10c and pump outlet stop valves 14a, 14
b, 14c, and relief valves 12a, 12b,
12c, relief pipes 11a, 11 provided with
b, 11c are generally provided.

In addition, each branch supply pipe has a pressure control valve 5a,
Take-out pipes 6a, 6b, 6c provided with 5b, 5c
are concatenated. The take-out pipe is provided between the pump and the check valve, but if the branch supply pipe is provided with the pump inlet stop valve, pump outlet stop valve, and relief pipe, the relief pipe is installed in the branch supply pipe. The connection may be made between the point connected on the pump outlet side and the point provided with the check valve.

The pressure regulating valves 5a, 5b, 5c and the main supply pipe 4 are connected to a pressure detector 7, a pressure regulator 8, and a plurality of automatic/manual switchers 9a, 9 arranged in parallel.
b, 9c.

The pressure detector 7 detects the pressure of the fluid in the main supply pipe and converts it into a signal. The pressure detector 7 is connected to a pressure regulator 8 by a signal transmission means. The pressure regulator 8 sends signals to the pressure regulating valves 5a, 5b, and 5c to automatically open and close the pressure regulating valves so that the deviation between the signal sent from the pressure detector and the preset pressure is zero. belongs to. In addition, automatic/manual switching devices 9a, 9b,
9c is a pressure regulator 8 and pressure regulating valves 5a, 5b,
5c, and are connected to the pressure regulator 8 by respective signal transmission means, and the pressure regulator valve 5
A, 5b, and 5c are connected correspondingly. The automatic/manual switching devices 9a, 9b, and 9c independently cut off signals sent from the pressure regulator 8 to the pressure regulating valves 5a, 5b, and 5c.
c can be operated independently and manually. When operating the pressure control valve manually, the automatic/
It is preferable to provide external input devices 17a, 17b, 17c for sending constant signals to the manual switching devices 9a, 9b, 9c, respectively, and to open and close the pressure regulating valve by manually adjusting the signals.

As the signal, known signals such as air pressure, oil pressure, and electric current can be used.

[Effect]

Next, according to the usage mode of the device of the present invention, its operation is performed in the fluid supply device of FIG. 2, for example,
Pump 2a is stopped as a backup pump, and pump 2a is stopped as a backup pump.
A case will be described in which the pump 2a and the pump 2b are switched when the pumps b and 2c are used regularly.

When starting the pump 2a, by manually switching the opening and closing of the pressure regulating valve 5a using the automatic/manual switch 9a, the pressure regulating valve 5a can be manually fully opened from the external input device 17a. If the pump 2a is started here, the entire amount of the fluid sent from the pump 2a is taken out by the take-out pipe 6a, and furthermore, the backflow of fluid from the main supply pipe 4 to the take-out pipe 6a is prevented by the action of the check valve 13a. Therefore, the pressure of the fluid in the main supply pipe 4 does not change at all due to activation of the pump 2a. The automatic/manual changeovers 9b and 9c are set to automatic.

When switching from the pump 2a to the pump 2b, the automatic/manual switch 9a remains switched to manual and gradually throttles the pressure control valve 5a to increase the amount of fluid supplied from the branch supply pipe 3a to the main supply pipe 4. . During this time, the pressure of the fluid in the main supply pipe 4 is kept constant by automatically adjusting the pressure regulating valves 5b and 5c by the pressure regulator 8 based on the pressure detected by the pressure detector 7. And pressure detectors 15a, 15b, 15c provided on each branch supply pipe.
The pressure detected by the pressure indicators 16a, 16b,
16c, which allows the pressure of the fluid in the branch supply pipe 3a to be read at the other branch supply pipe 3.
It can be confirmed that the pressure of the fluid in b and 3c has become almost the same. Branch supply pipes 3a, 3
When the pressures in b and 3c become almost the same, the automatic/manual switch 9a switches the opening/closing of the pressure regulating valve 5a to automatic, and then the automatic/manual switch 9b switches the opening/closing of the pressure regulating valve 5b to manual. Switch.

When the pump 2b is stopped, the pressure regulating valve 5b
is switched to manual by the automatic/manual switch 9b, so the pressure regulating valve 5b can be opened gradually manually, thereby increasing the flow rate of fluid to the take-out pipe 6b and removing the main flow from the branch supply pipe 3b. The amount of fluid supplied to the supply pipe 4 decreases. Furthermore, the backflow of fluid from the main supply pipe 4 to the branch supply pipe 3b is prevented by the action of the check valve 13b. On the other hand, the pressure of the fluid in the main supply pipe 4 is maintained constant by being actuated by a pressure regulator 8 based on the pressure detected by the pressure detector 7 and by automatically adjusting the pressure regulating valves 5a and 5c. Then, when the pressure control valve 5b of the take-out pipe 6b connected to the branch supply pipe 3b is fully opened, all the fluid in the branch supply pipe 3b is taken out from the take-out pipe 6b, so the pump 2b is stopped at this point. By this, the pump 2 can be operated without changing the pressure of the fluid in the main supply pipe 4.
b can be stopped.

By the above-described operation, it is possible to completely prevent pressure fluctuations in the fluid in the main supply pipe 4 during pump switching and to transport the fluid without causing any stress on the device.

Note that it is preferable that the fluid taken out from the takeout pipe be circulated to the tank 1.

Furthermore, when repairing or inspecting the stopped pump 2b, the pump inlet stop valve 10b and the pump outlet stop valve 14b may be closed.

Although the present invention has been described above with reference to the case where there are three branch supply pipes, there is no particular restriction on the number of branch supply pipes as long as there are two or more branch supply pipes.

〔effect〕

As can be understood from the above description, according to the fluid transport device of the present invention, when the pump is switched during continuous fluid transport, a sudden pressure increase in the fluid in the pipe due to the activation of the pump, and a sudden increase in the pressure of the fluid in the pipe due to the stoppage of the pump occur. The sudden drop in pressure of the fluid in the main supply pipe can be alleviated by the outlet pipes connected to each branch supply pipe, and when the pump is switched, the fluid pressure in the main supply pipe can be maintained at a constant level without strain on the device, allowing fluid transport. can be done.

The fluid transport device of the present invention can contain water, oil, organic solvents,
It is suitably used when incompressible fluids such as solutions are continuously transported at a constant pressure.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional fluid transport device, and FIG. 2 is a schematic diagram of a fluid transport device of the present invention. Also, 1 is a tank, 2a, 2b, 2c are pumps, 3a, 3b, 3c are branch supply pipes, 4 is a main supply pipe, 5, 5a, 5b, 5c are pressure regulating valves,
6, 6a, 6b, 6c are extraction pipes, 7, 15
a, 15b, 15c are pressure detectors, 8 is a pressure regulator, 9a, 9b, 9c are automatic/manual switchers, 10
a, 10b, 10c are pump inlet stop valves, 11a,
11b, 11c are relief pipes, 12a, 12
b, 12c are relief valves, 13a, 13b, 13
c is a check valve, 14a, 14b, 14c are pump outlet stop valves, 16a, 16b, 16c are pressure indicators,
17a, 17b, and 17c indicate external input devices, respectively.

Claims (1)

[Claims] 1. The tank and the main supply pipe are connected by a plurality of branch supply pipes arranged in parallel, each branch supply pipe is provided with a pump and a check valve in order from upstream, and between the pump and the check valve, , a pressure detector and a pressure indicator are installed in each branch supply pipe, and a take-out pipe with a pressure regulating valve is connected;
In addition, a pressure detector is provided in the main supply pipe, and the pressure detector is connected to a pressure regulator and an automatic/manual switch arranged in parallel corresponding to each of the plurality of pressure regulating valves. A fluid transport device characterized in that it is connected to a pressure regulating valve.