JPH0626608A - Water supplying device - Google Patents

Abstract

PURPOSE:To provide a water supplying device in which a water hammer in a pipe between a shut-off valve and a control valve is prevented from occurring. CONSTITUTION:A bypassing pipe 10 branched from an upstream side of an inlet port of a shut-off valve 1 in a pipe 4 having the shut-off valve 1 and a control valve 2 arranged in series and merged at a pipe 4 between the shut-off valve 1 and the control valve 2 is provided. The bypassing pipe is provided with a bypassing shut-off valve 3 having a smaller volume than that of the shut-off valve 1 and then the bypassing shut-off valve 3 is operated in response to a signal got from a pressure sensing device 11. Before the shut-off valve 1 is opened, the bypassing shut-off valve 3 is opened and the pipe between the shut-off valve 1 and the control valve 2 is filled with water and then upon completion of filling of the water, the bypassing shut-off valve 3 is closed and the shut-off valve 1 is opened with an opening signal of the control valve 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply apparatus, and particularly suitable for preventing a water hammer which is likely to occur between a shutoff valve and a control valve in a water supply line in which the shutoff valve and the control valve are arranged in series. Water supply equipment.

[0002]

2. Description of the Related Art In a conventional water supply apparatus, as shown in FIG. 7, superheated steam from a primary superheater 5 is introduced into a secondary superheater 7 via a superheat desuperheater 6 to produce a superheat desuperheater 6. Water is introduced into the turbine 8 through a pipe provided with the control valve 2, and the superheated steam from the secondary superheater 7 is supplied to the turbine 8. Further, as shown in FIG. 8, the warm water to the economizer 15 is supplied to the drum 16 via the control valve 2.

In this configuration, since the control valve 2 is generally not excellent in blocking water and the like, the shutoff valve 1 is installed upstream of the shutoff valve 1 to deal with it. For this purpose, the shut-off valve 1 is closed when the control valve 2 is closed, and the shut-off valve 1 is fully opened when the control valve 2 is open to some extent. That is,
The shutoff valve 1 is fully opened by the open signal of the control valve 2 and fully closed by the closed signal.

In such a water supply device, when the shutoff valve 1 and the control valve 2 are not filled with water, the shutoff valve 1 is opened by the open signal of the control valve 2 (fully opened in a few seconds), High-pressure water flows between the shutoff valve 1 and the control valve 2 and collides with the control valve 2. In this case, even if the control valve 2 is fully open, the resistance of this valve is extremely larger than that of piping, so
There is a problem that water hammer occurs and the control valve 2 is broken.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a connection between the shut-off valve and the control valve before the control valve opens when the pipe or the like between the shut-off valve and the control valve is not filled with water. To provide a water supply device suitable for preventing water hammer that is likely to occur between the shutoff valve and the control valve after the shutoff valve is opened by water filling the space such as the pipe without water hammer. is there.

[0006]

In order to achieve the above object, the present invention provides a shutoff valve that branches from an upstream side of an inlet of a shutoff valve of a water supply line in which a shutoff valve and a control valve are arranged in series. This is achieved by providing a bypass line that joins the water supply line with the control valve, and providing this bypass line with a bypass shutoff valve having a smaller capacity than the shutoff valve. Further preferably, it is achieved by providing a pressure detecting device in the water supply line between the shutoff valve and the control valve, and by making the bypass shutoff valve close when the pressure value due to water filling is detected by this pressure detecting device. .

[0007]

[Function] Open the bypass shutoff valve before opening the shutoff valve,
Water-fill the piping between the shutoff valve and the control valve. At this time, since the bypass cutoff valve has a smaller capacity than the cutoff valve, the flow velocity of the water flowing between the cutoff valve and the control valve is small, and water hammer is generated in the pipe or the like between the cutoff valve and the control valve. Can be filled with water without any problems.

When the water filling is completed, it is confirmed by the pressure detecting device, and the bypass shutoff valve is closed immediately after the water filling is completed. As a result, the shutoff valve opens due to the open signal of the control valve, and the non-volume of water hardly changes even when the pressure of water rises, so that water suddenly flows into the piping, etc. between the shutoff valve and the control valve. Without doing so, water hammer will never occur.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing an embodiment of the water supply device of the present invention, and FIG. 2 is a graph showing changes over time in the piping pressure between the shutoff valve and the control valve and the opening of various valves in the device of FIG. is there.

FIG. 1 shows a system around a superheat desuperheater of a steam generator, and a superheat desuperheater 6 is installed between a primary superheater 5 and a secondary superheater 7. Water injection into the superheat desuperheater 6 is introduced by a main water supply pipe 9 and flows into the superheat desuperheater 6 via a shutoff valve 1 and a control valve 2 for adjusting the amount of water injected. The superheated steam from the secondary superheater 7 is supplied to the turbine 8.

Further, a bypass pipe 10 which joins the pipe 4 between the shutoff valve 1 and the control valve 2 from the upstream side of the inlet of the shutoff valve 1 is installed. Also, a small capacity bypass cutoff valve 8 is installed. A pressure detection device 11 is installed in the pipe 4 upstream of the control valve 2, and the bypass cutoff valve 3 is activated by a signal from the pressure detection device 11.

Next, the change over time of the valve opening and the piping pressure between the shutoff valve 1 and the control valve 2 will be described with reference to FIG. Figure 2
, 12 indicates the opening degree of the bypass cutoff valve 3, and 13
Indicates the opening degree of the shutoff valve 1, and 14 indicates the opening degree of the control valve 2.

First, the bypass shutoff valve 3 is opened before the shutoff valve 1 is opened.
Is opened, and water is filled in the space of the pipe 4 between the shutoff valve 1 and the control valve 2 via the bypass pipe 10. When the water filling is completed, the water pressure in the pipe is detected by the pressure detection device 11, and the bypass cutoff valve 3 is closed before the water pressure immediately increases based on the detected value.

Next, even if the shutoff valve 1 is opened by the opening signal of the control valve 2 (fully opened in a few seconds), the pipe 4 between the shutoff valve and the control valve 2 is filled with water, and the water pressure rises. Also, since the non-volume of water does not change, there is no sudden inflow of water and the occurrence of water hammer can be prevented. Therefore, the pipe 4 between the shutoff valve and the control valve 2 can be operated without causing water hammer.

FIG. 3 is a system diagram showing another embodiment of the water supply apparatus of the present invention, and FIG. 4 is a graph showing changes with time in the internal pressure of the economizer and the opening of various valves in the apparatus of FIG. Is.

FIG. 3 shows a system around the economizer of the steam generator. Water supply to the economizer 15 flows through the shutoff valve 1 and the economizer 10 is installed at the outlet. The flow rate is adjusted by the valve 2 so as to flow into the drum 16.

Also in this embodiment, a bypass pipe 10 is provided as in the embodiment shown in FIG.
A small capacity bypass shutoff valve 3 is installed at 0
A pressure detection device 11 is installed in the pipe 4 on the upstream side.

Also in the apparatus shown in FIG. 3, the operations of the shutoff valve 1, the pressure detection device 11, the bypass shutoff valve 3 and the control valve 2 are substantially the same. In this case, as shown in FIG. The internal pressure of the inside shows the behavior substantially the same as the piping pressure in FIG. Therefore, it is possible to prevent the occurrence of water hammer in the pipe in the economizer 15.

FIG. 5 is a system diagram showing still another embodiment of the water supply system of the present invention. In FIG. 5, in addition to the device having the primary superheater 5 and the secondary superheater 7 each having the same configuration as in FIG. 1, the secondary superheater 7 and the tertiary superheater are provided. The secondary superheat desuperheater 17 is installed between 18,
A third superheat desuperheater 19 is installed between the third superheater 18 and the fourth superheater 20.

A water supply pipe 4 is connected to each of the primary superheat desuperheater 6, the secondary superheat desuperheater 17, and the third superheat desuperheater 19, and these pipes are connected to the bypass pipe 10 and its pipes. Equipped with the bypass cutoff valve 3 installed,
The superheated steam from the fourth superheater 20 is supplied to the turbine 8.

In this embodiment, the primary superheat desuperheater 6,
The bypass pipe 10 and the bypass shutoff valve 3 installed in each pipe connected to the secondary superheat desuperheater 17 and the tertiary superheat desuperheater 19 respectively operate in the respective pipes by substantially the same operation as described above. Hammer can be prevented.

FIG. 6 is a system diagram showing still another embodiment of the water supply system of the present invention, which is a low temperature reheater 21 and a high temperature reheater 23.
A reheat dehumidifier 22 is installed between the reheat dehumidifier 22 and the pipe 4, which is connected to the reheat dehumidifier 22 is provided with a bypass pipe 10, and the bypass pipe 10 is provided with a bypass shutoff valve 3. The steam from the high temperature reheater 23 is supplied to the turbine 8. Also in this embodiment, the water hammer in the pipe 4 can be prevented by the operation of the bypass pipe 10 and the bypass cutoff valve 3.

Although the pressure detecting device is not shown in FIGS. 5 and 6, the water hammer is prevented based on the operation of the bypass cutoff valve 3 as described above based on the signal from the pressure detecting device. be able to.

[0024]

As described above, according to the present invention,
Piping between the shut-off valve and the control valve by operating the bypass shut-off valve before opening the shut-off valve when starting water supply when the pipe between the shut-off valve and the control valve is not filled with water. It is possible to perform water filling without the occurrence of water hammer in the above, and when the shutoff valve is opened to supply water, the water hammer does not occur in the pipe between the shutoff valve and the control valve.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a water supply device of the present invention.

FIG. 2 is a graph showing changes over time in the pipe pressure and valve opening in FIG.

FIG. 3 is a system diagram showing another embodiment of the water supply device of the present invention.

FIG. 4 is a graph showing changes with time in the internal pressure of the economizer and the valve opening degree in the apparatus of FIG.

FIG. 5 is a system diagram showing still another embodiment of the water supply device of the present invention.

FIG. 6 is a system diagram showing still another embodiment of the water supply device of the present invention.

FIG. 7 is a system diagram showing an example of a conventional water supply device.

FIG. 8 is a system diagram showing another example of a conventional water supply device.

[Explanation of symbols]

 1 Shutoff valve 2 Control valve 3 Bypass shutoff valve 4 Piping 5 Primary superheater 6 Superheat desuperheater 7 Secondary superheater 9 Water supply pipe

Claims (2)

[Claims] 1. A bypass line that branches from an upstream side of an inlet of a shutoff valve of a water supply line in which the shutoff valve and the control valve are arranged in series and joins a water supply line between the shutoff valve and the control valve. A water supply device, wherein the bypass line is provided with a bypass cutoff valve having a smaller capacity than the cutoff valve. 2. A pressure detecting device is provided in a water supply line between the shutoff valve and the control valve, and the bypass shutoff valve is operated based on a signal from the pressure detecting device. The water supply device according to claim 1.