JPS599726B2 - safety valve test equipment - Google Patents

Description

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

Generally, the operation test of a safety valve 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, one 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 the steam is stored in a pressure vessel and the steam is sent to the safety valve for a short period of time when the steam is blown out from the safety valve. If supplied, 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 set up a steam reservoir and utilize the volumetric expansion of the steam stored in the steam pool as it falls from the blow-out pressure to the blow-up pressure. There is a method of passing steam through a safety valve.Another method is to install a heat storage, store saturated water in the heat storage, and when the pressure drops, part of the saturated water turns into steam due to the enthalpy reduction of the saturated water. There is a method that takes advantage of this phenomenon and allows the generated steam to pass through a safety valve.

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 also includes a high-pressure steam reservoir that receives steam from the boiler and stores it in a high-pressure state. High-pressure steam from a high-pressure steam reservoir is supplied to the steam reservoir.

In such a device, the steam reservoir operates at, for example, 80 kg/d, while the initial pressure of the high-pressure steam reservoir is, for example, 15 kg/d.
If it is 0 kg/d, the effective differential pressure at which steam can expand is 70 kg/C-TL, and the corresponding amount of steam can be obtained, so the high-pressure steam reservoir can have an extremely small internal volume. Become.

Of course, there is no risk of water droplets getting mixed into the steam in the steam reservoir, so wear and tear on the safety valve can be prevented and no leakage will occur when the valve is closed. In order to effectively use a high-pressure steam reservoir for safety valve testing, 1.
Since it is necessary to feed the required amount of high-pressure steam to the steam reservoir within a short period of about seconds, the connecting steam pipe between the two must have an appropriately sized inner diameter, and an appropriate A pressure regulating valve is used.

This pressure regulating valve is opened to an appropriate opening immediately when the test safety valve is pulled up and the pressure in the steam reservoir drops, so expanding steam from the high-pressure steam reservoir is sent in and the pressure in the steam reservoir is lowered. . 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.

A high-pressure steam reservoir 5 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 pressure regulating 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 high-pressure steam reservoir 5 is connected to the muffler 13 through a steam pipe 15 having a valve 14. has been done. The test safety valve 16 is attached to the steam reservoir 1 by a fastening device. The pressure regulating valve 9 is equipped with a detector 1 that detects the pressure when the pressure in the steam reservoir 1 drops.
7, it is opened to an appropriate opening 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/CfI is supplied to the steam reservoir 1 through
Can be stored in L. At the same time, part of the steam from the boiler 2 is supplied to the high-pressure steam reservoir 5 through the steam pipe 7 with the valve 6 opened, for example, 150 kg/C! It can be saved at 11. At this time, the valve 8 in front of the pressure regulating valve 9 is closed, and steam does not flow from the high-pressure steam reservoir 5 to the steam reservoir 1. The steam reservoir 1 and the high-pressure steam reservoir 5 require the steam to pass through them in order to heat the containers, so the valves 11 and 14 of the steam pipes 12 and 15 connected to the silencer 13, respectively, are closed. It opens and sends the steam to the silencer 13 where it is dumped into the atmosphere.

Next, when the valves 11 and 14 are closed and the valve 8 in front of the pressure regulating valve 9 is opened, the pressure difference between the high pressure steam reservoir 5 and the steam reservoir 1 is created because the pressure regulating valve 9 is not completely closed. As a result, the internal pressure of the high-pressure steam reservoir 5 decreases, and the expanded steam flows to the steam reservoir 1.

Eventually, the internal pressure of the steam reservoir 1 rises to, for example, 80k9/(-fl), and when the test safety valve 16 opens, a large amount of steam escapes from the safety valve 16, so the pressure inside the steam reservoir 1 drops rapidly. This pressure is detected by the detector 17, and the pressure regulating valve 9 is immediately opened by the detector 17, and the high pressure steam reservoir 5 is opened.
Steam is sent from the steam reservoir 1 to the steam reservoir 1. Therefore, the internal pressure of the high-pressure steam reservoir 5 is 150 kg/(from 1771 to 80 kg/
Since the pressure drops to Crii and a corresponding amount of steam is supplied to the steam reservoir, 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 to ensure that the safety valve is tested. As detailed above, the safety valve testing device according to the present invention uses a small-capacity boiler, a steam reservoir with a small internal volume, and a high-pressure steam reservoir to ensure that the amount of steam necessary to open the safety valve to a specified opening degree for a certain period of time is maintained. Since the test equipment can be supplied, safety valve tests can be performed accurately, and the entire equipment can be made smaller, which has the effect of significantly reducing manufacturing costs compared to conventional test equipment.

[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... High pressure steam reservoir, 9... Pressure regulating valve, 13... Silencer, 1
6... 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 boiler that receives steam from the boiler, stores steam at a higher pressure than the steam in the steam reservoir, and supplies this steam to the steam reservoir when the pressure of the steam reservoir drops. A safety valve test device consisting of a high-pressure steam reservoir.