JPS587866B2 - Koonko Atsuri Yutayouben - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shutoff valve in a double pipe used as a conduit for high temperature and high pressure fluid.

With the advancement of technology, for example, the internal fluid of heat exchangers in nuclear power generation facilities has become high temperature and high pressure (e.g. 1000°C).
, 40 kg/cm'g), and as a conventional single pipe for guiding this internal fluid, materials that can withstand high pressure at high temperatures have not yet been developed, so currently, a pressure pipe and an inner pipe are used. Double piping is used.

In this double piping, a pressure pipe is provided on the outside, and an inner pipe having a smaller diameter than the pressure pipe is provided concentrically with a gap between the inner peripheral surface of the pressure pipe and the outer peripheral surface of the inner pipe. It is something.

A high-temperature, high-pressure fluid is flowed into the inner tube, and a low-temperature fluid with approximately the same pressure as the fluid in the inner tube (e.g., 550°C, 40 kg/cm'g) is flowed into the gap between the pressure tube and the inner tube.
) is set to flow.

By doing this, the pressure tube receives pressure in the low temperature range, and although the inner tube is in the high temperature range, the pressure applied to its inner and outer surfaces is almost equal, and the pressure is virtually unchanged. It maintains its strength as piping for high-temperature, high-pressure fluids.

By the way, a valve that can be put to practical use to shut off the high-temperature, high-pressure fluid flowing through the inner pipe in this double piping for high-temperature, high-pressure fluid has not yet been developed, and currently there are no valves that can be used to shut off the internal fluid of this double piping. When the temperature of the fluid in the inner pipe has dropped sufficiently, it is led from the double pipe to a conventional single pipe, and a conventional shutoff valve is connected to the single pipe.

The present invention has been made in view of the current situation, and it is an object of the present invention to provide a valve that can shut off high-temperature, high-pressure fluid flowing through the inner pipe of a double pipe.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a shutoff valve in a double pipe for high-temperature, high-pressure fluid according to the present invention will be described below with reference to the drawings.

1 is the inner pipe of the valve, which is connected to the inner pipe of the double piping (not shown), and 2 is the body on the outer pipe side of the valve, which is the part that connects to the pressure pipe of the double piping (not shown). It has a pressure-resistant structure.

An innermost tube 4 having a pressure equalizing hole 4a is provided with a gap on the inner peripheral side of the inner tube 1, and a heat insulating material 3 is inserted into the gap.

A partition wall 7 is provided inside the body 2 with a gap, and a valve plate 5 is penetrated and fixed by welding at a concentric position of the pressure pipe connection portion of the body 2 on the partition wall 7. A structure consisting of an inner pipe 1, a heat insulating material 3, and an innermost pipe 4 is fitted and welded, and the inner pipe 1 is supported concentrically by a support 8 on the inner peripheral surface of the pressure pipe connection part of the body 2.
The gap between the inner circumferential surface of the pressure pipe connection part of the body 2 and the outer circumferential surface of the inner tube 1 and the gap between the inner circumferential surface of the body 2 and the outer circumferential surface of the partition wall 7 make it possible to A flow path for low-temperature and high-pressure fluid is formed that connects to the gap between the inner tube and the inner tube.

The distance between the ends of the valve plate 5 that protrude inwardly through the partition wall 7 is a distance between the valve disc 6 fixed to the stem 9.
The spacing is such that they can be fitted into sliding contact, and a stellite embossing 95a is applied to the sliding contact portions.

The opening 6a of the valve disk 6 is configured to substantially match the inner diameter of the innermost tube 4 when the stem 9 is pulled upward to open the valve.

Note that the upper part of the joint between the body 2 and the partition wall 7 is sealed with a packing or the like to prevent internal fluid from leaking from the flange part of the body 2, and the lower part is fitted with projections and recesses to the extent of a steady rest.

Next, the operation of the shutoff valve of the present invention configured as described above will be explained.

When the valve is in the closed state as shown in the figure, the high-temperature, high-pressure fluid flowing in the inner pipe 1 as shown by the arrow flows through the valve plate 5.
The sliding surface of the valve disk 6 is completely sealed and completely shut off.

On the other hand, the low-temperature and high-pressure fluid that has flowed through the gap between the pressure pipe and the inner pipe of the double piping flows into the gap between the pressure pipe connection part of the body 2 and the inner pipe 1 as shown by the arrow, and then flows into the gap between the pressure pipe connection part of the body 2 and the inner pipe 2 and the partition wall 7 to reach the gap between the pressure pipe connection part of the body 2 on the outlet side and the inner pipe 1, and lead to the gap between the pressure pipe and the inner pipe of the double piping. It will be destroyed.

Now, when the stem 9 is pulled upward to open the valve, when the sliding surfaces of the valve plate 5 and the valve disk 6 separate t, the high-temperature, high-pressure fluid in the inner tube 1 flows through the opening. It flows into the partition wall 7 through 6a and stagnates in a full state.

Further, the stem 9 is pulled upward to open the opening 6a into the inner tube 1, and finally the innermost tube 4 and the opening 6a are aligned to open a passage for the high-temperature, high-pressure fluid in the inner tube 1. .

In this way, the high-temperature, high-pressure fluid within the inner tube 1 is directly blocked, but the low-temperature, high-pressure fluid path is not affected.

In addition, due to the piping system of double piping, for example, high-temperature, high-pressure fluid in the inner pipe of the double piping exchanges heat with a heat exchanger on the downstream side of the valve, and then exchanges heat as low-temperature, high-pressure fluid with the pressure pipe of the double piping. In the case of a closed circuit that returns to the gap between the pipe and the pipe,
By blocking the high-temperature, high-pressure fluid in the inner tube 1, the low-temperature, high-pressure fluid flowing through the gap between the pressure tube connection portion of the body 2 and the inner tube 1 is also blocked at the same time.

Of course, in the case of an open circuit as shown, the low-temperature, high-pressure fluid flowing through the gap between the pressure pipe connection part of the body 2 and the inner pipe 1 has a low temperature, so it can be guided to the conventional single pipe, and the fluid flows into the single pipe. If a conventional valve is provided, it is possible to shut off the low temperature and high pressure fluid.

Next, we will discuss the effects of heat and pressure on high-temperature, high-pressure fluids.

First, the internal fluid in the inner tube 1 is a high-temperature, high-pressure fluid (for example, 100%
0℃, 40kg/cm'g), and body 2
The fluid flowing through the gap between the pressure pipe connection part and the inner tube 1 and the gap between the body 2 and the partition wall 7 is a low-temperature, high-pressure fluid (for example, 550° C., 40 kg/cm'g).

Furthermore, the inside of the partition wall 7 is filled with high-temperature, high-pressure fluid that has flowed in when the valve is opened and closed, and is stagnant therein.

All of these internal fluids have approximately the same pressure (4 0
kg/cm'g).

In this state, the innermost tube 4 is heated to a high temperature (1000 degrees Celsius), while the inner tube 1 is heated to a low temperature (550 degrees Celsius). Temperature interference with the heat insulating material 3 is prevented by the heat insulating material 3.

Further, the innermost tube 4 is subjected to an internal pressure of 40 kg/cm'g, and the inner tube 1 is subjected to an external pressure of 40 kg/cm'g, and the heat insulating material 3 is crushed, but the pressure equalizing hole 4a Therefore, no internal pressure is applied to the innermost tube 4,
Moreover, the heat insulating material 3 is prevented from collapsing, and the pressure applied to the inner and outer surfaces of the inner tube 1 is equalized, so that substantially no pressure is applied.

A valve plate 5 passes through the partition wall 7 and is fixed by welding, and the inner pipe 1 and the innermost pipe 4 are integrally connected to the valve plate 5. When the valve is closed, the valve plate 5
The valve disk 6 and the valve disk 6 are in close contact with each other at sliding surfaces, and these members are in a state where heat is conducted to each other.

The temperature of the portion exposed to the low-temperature and high-pressure flow path formed by the inner tube 1, the partition wall 7, and the body 2 is low (550 degrees Celsius).
), while the innermost tube 4 and the valve disc 6 are heated to a high temperature.

In addition, the inside of the partition wall 7, the periphery of the opening 6a of the valve disk 6 exposed inside the partition wall, and the outer circumference of the valve plate 5 are exposed to the fluid stagnant inside the partition wall 7 and the low-temperature fluid flowing outside the partition wall 7. It is heated to a certain temperature by heat exchange and convection due to heat radiation from the stem 9 and valve disk 6.

Each member in these three types of temperature atmosphere maintains thermodynamic equilibrium and balances. For example, the sliding contact surface between the valve plate 5 and the valve disc 6 is not necessarily at a high temperature (1000 degrees Celsius).
rather than being cooled to a temperature at thermodynamic equilibrium.

On the other hand, the pressure is only applied to the body 2 as internal pressure, and the pressure on the inner and outer surfaces of other members is equal and virtually no pressure is applied.

As detailed above, the shutoff valve in the double piping for high-temperature, high-pressure fluid according to the present invention completely shuts off the low-temperature, high-pressure fluid passage and the high-temperature, high-pressure fluid passage that communicate with the heat medium passage of the double piping. The valve disk, which is thermodynamically balanced and opens and closes the high-temperature, high-pressure fluid flow path, is installed in an atmosphere that is almost the same as the high-temperature, high-pressure fluid flow path. Since there is no contact with fluid, no thermal stress is generated due to temperature differences.

In addition, since the high-temperature, high-pressure fluid flow path and the low-temperature, high-pressure fluid flow path are perfectly balanced in terms of pressure, no pressure is applied to the valve disc that opens and closes the high-temperature, high-pressure fluid flow path, allowing smooth opening and closing operations. It can be said that this is an epoch-making device that has never been seen before as a shutoff valve for double piping for high temperature and high pressure fluids.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of a shutoff valve in a double pipe for high-temperature, high-pressure fluid according to the present invention. 1...Inner tube, 2...Outer tube side body, 3
...Insulation material, 4...Innermost pipe, 4a.
・・・・・・Pressure equalization hole, 5・・・・・・Valve plate, 5
a... Stellite mound, 6... Vulp disk, 7... Bulkhead, 8... Support, 9... Stem.

Claims (1)

[Claims] 1. A partition wall is provided with a gap inside the outer pipe side body of a pressure-resistant structure having portions connected to pressure pipes of a double piping for high-temperature and high-pressure fluids on both the left and right sides, and a partition wall is provided with a gap through the left and right walls of the partition wall, respectively. A valve plate is fixed concentrically with the pressure pipe connection part of the double piping, and an inner pipe inserted concentrically from the pressure pipe connection part of the body is connected to each valve plate, so that high temperature and high pressure fluid flows inside the inner pipe. A low-temperature, high-pressure fluid flow path is formed between the inner wall surface of the body, the partition wall and the inner pipe, and the inner pipe is provided with a heat insulating layer and a pressure equalizing hole, and the left and right valve plates protrude into the partition wall. A shutoff valve in double piping for high temperature and high pressure fluids, in which a valve disc that shuts off the flow path of high temperature and high pressure fluids is slidably fitted between the parts so as to be movable up and down.