JPS599725B2 - safety valve test equipment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a safety valve testing device.

Generally, a safety valve operation test is performed by flowing steam at a flow rate sufficient to lift the valve stem of the safety valve to a specified opening degree for a predetermined period of time, for example, 1 second, and check the blowout pressure, lift-up amount,
This is done by measuring upwelling pressure, etc.

By the way, when a safety valve has a large capacity, it blows out a large amount of steam, but the blowing time is short as mentioned above, so steam is stored in a pressure vessel and steam is supplied to the safety valve for a short period of time when the steam is blown out from the safety valve. By doing so, the test device can be made smaller.

In addition, the safety valve has a pressure difference between the blow-out pressure and the blow-up pressure.
It is specified to be 7 to 10% or less of the blowout pressure, and in reality, many safety valves have a pressure difference of this level. For this reason, one of the conventional testing methods for safety valves is to install a steam reservoir and utilize the volumetric expansion when the steam stored in the steam column drops from the blow-out pressure to the blow-up pressure. There is a method to pass the steam to the safety valve.Another method is to install a heat storage device, store saturated water in the heat storage device, and when the pressure drops, part of the saturated water becomes steam due to the enthalpy reduction of the saturated water. There is a method of passing the generated steam to a safety valve by utilizing the phenomenon that changes to .

According to this method, the amount of steam supplied to the steam reservoir or heat storage device can be small in inverse proportion to the time required to store steam in the steam reservoir or the time required to heat water in the heat storage device to saturated water. .

However, in the conventional method described above, in the case of a steam reservoir,
The internal volume of the steam reservoir becomes considerably large in proportion to the capacity of the safety valve, and this internal volume needs to be extremely large when the blowout pressure of the safety valve becomes low.

In addition, in the case of a heat storage device, since water droplets mix with the generated steam and wear out the safety valve when blowing out, it is necessary to remove the water droplets. The pressure drop required for steam to pass through increases, reducing the differential pressure available as a heat storage, making it difficult for steam to flow, and causing problems in testing safety valves.
The present invention aims to eliminate the drawbacks of these methods and to provide a safety valve testing device that allows the above-mentioned safety valve test to be carried out using a pressure vessel with a small internal volume. The safety valve test device of the present invention connects a steam reservoir with a relatively small internal volume equipped with a test safety valve to a small-capacity boiler, and is provided with a heat storage device that receives heated steam from the boiler. It is designed to supply steam to a steam reservoir.

In such a device, the steam reservoir operates at, for example, 80 kg/cd, while the initial pressure of the regenerator is set at, for example, 150 kg/cd.
g/cd, the effective differential pressure of the heat storage device is 70 kg/cd.
Since it becomes Cd and the corresponding amount of vapor is obtained,
It is sufficient that the heat storage device has an extremely small internal volume.
In addition, a steam separator is installed in the heat storage device, in the connecting steam pipe between the heat storage device and the steam reservoir, or in the path of the steam generated by the heat storage device in the steam reservoir to remove water droplets from the steam. Even if enough is taken to ensure good steam/water separation, there is no problem as the resistance is extremely small compared to the above effective differential pressure, and there is also sufficient driving differential pressure to move the steam from the heat storage to the steam reservoir. Therefore, steam does not become difficult to flow.

Of course, in order to effectively use the heat storage device for safety valve testing, it is necessary to generate steam from the heat storage device within a short period of about 1 second.
Since it is necessary to send the required amount of this to the steam reservoir for testing the safety valve, the connecting steam pipe between the two should have an appropriately sized inner diameter and be equipped with an appropriate control valve in the middle. be. When the test safety valve lifts up and the pressure in the steam reservoir drops, this control valve immediately opens to an appropriate opening to lower the pressure in the heat storage, generate steam from the heat storage, and send the steam to the steam reservoir. , which serves to prevent the pressure in the steam reservoir from decreasing. An embodiment of the safety valve testing device according to the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a steam reservoir, to which a boiler 2 is connected via a steam pipe 4 having a valve 3.

Reference numeral 5 denotes a heat storage device, which is connected to the boiler 2 through a steam pipe 7 having a valve 6, and to the steam reservoir 1 through a steam pipe 10 having a valve 8 and a control valve 9.

A muffler 13 for releasing excess steam is connected to the steam reservoir 1 through a steam pipe 12 having a valve 11, and the heat storage device 5 is connected to the muffler 13 through a steam pipe 15 having a valve 14. ing. The test safety valve 16 is attached to the steam reservoir 1 by a fastening device. In addition, the control valve 9 is the steam reservoir 1
When the pressure decreases, a detector 17 detects the pressure and opens the opening to an appropriate degree. Next, the operation of the safety valve testing device according to the present invention constructed as above will be explained.

The steam generated from the boiler 2 is passed through the steam pipe 4 with the valve 3 opened.
For example, 70 kg/CII is supplied to the steam reservoir 1 through
Can be stored in L. At the same time, a part of the steam from the boiler 2 is supplied to the regenerator 5 through the steam pipe 7 with the valve 6 opened, heating the water in the regenerator 5 and increasing the temperature by e.g.
kg/Clli of saturated water. At this time, the valve in front of the control valve 9 is closed, and no steam flows from the heat storage device 5 to the steam reservoir 1. In order to heat the water in the steam reservoir 1 and the heat storage device 5, it is necessary to allow the steam to pass through the container, so the valves of the steam pipes 12 and 15 connected to the silencer 13 are connected to the steam reservoir 1 and the heat storage device 5, respectively. Open 11 and 14 to release steam from silencer 13
and discard it into the atmosphere.

Next, when valves 11 and 14 are closed and valve 8 in front of control valve 9 is opened, control valve 9 is made so that it will not be fully closed, so the difference in pressure between heat storage device 5 and steam reservoir 1 will cause Therefore, heat storage device 5
The internal pressure of the container decreases, and the self-evaporated steam flows into the steam reservoir 1.

Eventually, the internal pressure of the steam reservoir 1 rises to, for example, 80 kg/Cl, and when the test safety valve 16 opens, a large amount of steam escapes from the safety valve 16, causing the pressure inside the steam reservoir 1 to drop rapidly. is detected by the detector 17, and the regulating valve 9 is immediately opened by the detector 17, and steam is sent from the heat storage device 5 to the steam reservoir 1. Therefore, the saturated water in the heat storage device 5 is 150 kg/(1-J mo Vf to 80 kg/CTi
1, and a correspondingly large amount of generated steam is supplied to the steam reservoir 1, so the pressure drop in the steam reservoir 1 is prevented, and the safety valve 1 is blocked by the steam blown out from the steam reservoir 1 for a certain period of time.
6 is opened to a specified opening degree to ensure that the safety valve 16 is tested.

As detailed above, the safety valve test device according to the present invention reliably supplies the amount of steam necessary to open the safety valve to a specified opening for a certain period of time using a small-capacity boiler, a steam reservoir with a small internal volume, and a heat storage device. As a result, the safety valve test can be carried out accurately, and the entire device can be made smaller, so manufacturing costs can be significantly reduced compared to conventional test devices.

[Brief explanation of the drawing]

The figure is a system diagram showing an embodiment of the safety valve testing device according to the present invention. 1...Steam reservoir, 2...Boiler, 3,6
, 8, 11, 14...Valve, 4, 7, 10, 12
, 15...Steam pipe, 5...Regenerator, 9
......Control valve, 13...Muffler, 16.
...Test safety valve, 17...Detector.

Claims (1)

[Claims] 1 A steam reservoir with a test safety valve attached using a tightening device,
A boiler that supplies steam to the steam reservoir; and a heat storage device that receives steam from the boiler, saturates internal water with the steam, and supplies steam generated by an effective pressure difference with the steam reservoir to the steam reservoir. Safety valve test equipment consisting of.