JPH02146375A - Valve - Google Patents

Abstract

PURPOSE:To maintain the sealing quality of a seat at a high temperature time such as a fire or the like and realize the prevention of damage, by forming out of a heat expansion material a seat either on the closing member side or the valve main body side of a valve which opens/closes by means of a valve shaft 90 degree/180 degree rotation operation. CONSTITUTION:When a butterfly valve 1 is heated by a fire or the like, a seat 4 of a heat expansion material expands, and seals firmly a space between a valve main body 2 and a disk 3, so a sure sealing is done even if the seat 4 is worn and damaged, and the passing of a fluid is deterred. If black lead which is of a heat expansion quality is used as a heat expansion material, it does not become ashes nor burn out at a high temperature, and its volume almost does not increase/decrease from a temperature change after heat expansion, and there is no occurrence of leak even after a temperature drop. When a sheet 4 is formed by putting a metal plate or metal foil 4a on a thin plate shaped heat expansion material 4b in layers, materials are hard to crumble after heat expansion, and the quality of sealing increases. Accordingly, damage due to the breakage of the valve or the like can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is mainly used for piping that conveys flammable or toxic gases or liquids. This invention relates to a valve that opens and closes by rotating the valve stem approximately 90 degrees or 180 degrees, and particularly relates to a valve that maintains or improves the sealing properties of its seat during high temperatures such as fires.

(Prior Art) In valves such as butterfly valves and ball valves that open and close by rotating the valve shaft by 90 degrees or 180 degrees, the seat on the valve body side or the seat on the closing member side has conventionally been
They were often made of synthetic resins or synthetic rubbers such as TFE (tetrafluoroethylene resin), NBR, and trill rubber).

These materials are extremely useful as materials with excellent sealing properties and durability, but they melt, decompose, or burn down in the event of a fire or other high temperature, causing the valve to lose its sealing properties and prevent flammable or toxic gases or liquids from entering. Unable to close.

Failure to prevent damage from occurring or spreading.

(Problems to be Solved by the Invention) The present invention provides a valve that opens and closes by rotating the valve shaft approximately 90 degrees or 180 degrees, such as a conventional butterfly valve or a ball valve, in which synthetic resin or synthetic rubber In view of the problem that the seat on the valve body side or the closing member side made of aluminum melts, decomposes, or burns out and loses the sealing performance of the valve, we have developed a new method that maintains the sealing performance of the seat even during high temperatures such as fires. The purpose is to provide a valve that can prevent damage.

Akane 1181 Also (Means for Solving the Problems) In order to solve the above problems, the present invention has made the valve stem approximately 90 mm.
A valve that opens and closes by rotating 180 degrees or 180 degrees,
The seat on the valve body side or the seat on the closing member side is made of a thermally expandable material.

Further, in this valve, the sheet was formed by laminating a metal plate or metal foil and a thin plate-like thermally expandable material.

In the above case, it is also possible to use thermally expandable graphite as the thermally expandable material.

(Function) When the valve of the present invention is heated due to a fire or the like, the seat on the valve body side or the closing member side, which is made of a thermally expandable material, expands to firmly connect the valve body and the closing member. Seal. Therefore, even if these sheets are somewhat worn or damaged.

Securely seal to completely prevent fluid flow.

In particular, if thermally expandable graphite is used as the thermally expandable material, it will not ash or burn out at high temperatures, and it will be thermally stable after thermal expansion and its volume will hardly increase or decrease due to temperature changes, so the temperature will change. No leakage occurs even after lowering.

In addition, the thermally expandable material used as the sheet material in the above,
In addition to sheets, if you use it for packing and gaskets,
In the event of a high temperature event such as a fire, it is possible to simultaneously prevent leakage from the seat portion as well as leakage to the outside of the valve body, further expanding and strengthening the effect of preventing fluid from flowing through.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially sectional front view showing a butterfly valve according to an embodiment of the present invention, and FIG. 2 is a vertical sectional view taken along the line XX of the butterfly valve shown in FIG.

In FIGS. 1 and 2, 2 is the valve body of the butterfly valve 1, 3 is a disc that is a closing member, 4 is a seat attached to the valve body 2, 5 is a valve stem, and 8 is a packing. The valve shaft 5 is divided into an upper valve shaft 5a and a lower valve shaft 5b, and the seat 4 is attached to the valve body 2 by screwing a seat presser 6 into the valve body 2. In addition, the upper valve shaft 5
A lever handle 7 with a locking mechanism is fixed to the upper end of a, and a disc 3 is fixed to the lower side of the upper valve shaft 5a and the upper end of the lower valve shaft 5b.

Although FIGS. 1 and 2 both show the valve in the closed state, the lever handle 7 is rotated after disengaging the locking mechanism, and the disc 3 is moved from the valve shaft 5 through the upper valve shaft 5a. Rotate it clockwise to open the butterfly valve 1.

The disc (sheet on the closing member side) 3 is made of thermally expandable graphite, which is a type of thermally expandable material, and has excellent sealing performance and durability.

Moreover, as shown in FIG. 3, if the sheet 4 is formed by laminating a metal plate or metal foil 4a and a thin plate-like thermally expandable material 4b instead of the sheet 4 of the above embodiment, after thermal expansion Thermal expandable material is less likely to collapse and sealing performance is increased.

Next, the operation of the above embodiment will be explained.

When the butterfly valve 1 is heated due to a fire or the like, the sheet 4 made of a thermally expandable material expands and tightly seals the space between the valve body 2 and the disc 3. Therefore, even if the seat 4 is worn or damaged, it is reliably sealed and completely prevents fluid from flowing through.

In particular, in this example, the sheet 4 is made of thermally expandable graphite, so it does not ash or burn out at high temperatures, and is thermally stable even after thermal expansion, so its volume hardly changes or changes with temperature changes. This prevents leakage even after the temperature drops.

In addition, if the packing 8 is also made of a thermally expandable material, it will simultaneously prevent leakage to the outside of the valve body 2 in the event of a fire or other high-temperature event.
The effect of preventing fluid flow is further expanded.

Look at the surface of the fruit According to the present invention, the following excellent effects can be obtained.

(1) The sheet does not melt, decompose, or burn down at high temperatures such as in a fire, so fluid leaks do not occur.

(2) Since the sheet expands during high temperatures such as fires and maintains the sealing properties of the sheet or raises the layer level, direct damage caused by valve breakage, etc. can be prevented, and the spread of damage can be reliably prevented.

(3) Even if the temperature drops after the fact, the sheet volume will not decrease and no leakage will occur.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view showing a butterfly valve according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view taken along the line XX in FIG. 1, and FIG. FIG. 2 is an enlarged partial cross-sectional view showing an embodiment of the invention. 1...Butterfly valve, 2...Valve body 3
...Closing member, disc 4...Sheet 4a...
Metal plate or metal foil 4b: thin plate-like thermally expandable material

Claims (3)

[Claims] (1) A valve that opens and closes by rotating the valve shaft approximately 90 degrees or 180 degrees, and in which the seat on the valve body side or the seat on the closing member side is formed of a thermally expandable material. (2) The valve according to claim 1, wherein the sheet is formed by laminating a metal plate or metal foil and a thin plate-like thermally expandable material. (3) The valve according to claim 1 or 2, wherein the thermally expandable material is thermally expandable graphite.