JPS5881272A - Butterfly valve - Google Patents

Abstract

PURPOSE:To prevent the leakage of gas in a metal seat water-sealing butterfly valve by providing a seal water distribution pipe on the circumference on the side of a valve seat for connecting a connecting water-feed passage to a seat ring with the seal water distribution pipe via radial drill holes. CONSTITUTION:A valve body 2 performs closing contact in a valve main body 1 via a seat ring 4. A seal water distribution pipe 5 is provided between the seat ring 4 and the valve body 2. A groove 9 is grooved on the center of the periphery of the seat ring 4, and connected to the seal water distribution pipe 5 via a number of drill holes 8 provided radially. The water supplied from a hole 10 via a valve stem 3 and an injection port 11 is conducted to the groove 9 via the seal water distribution pipe 5 and drill holes 8, and jetted out to a seat part 12 of the seat ring 4 for preventing the leak-in of the air from outside.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in butterfly valves, particularly metal seat water seal butterfly valves.

Conventional metal-touch butterfly valves had a defect that made it difficult to avoid leakage, and were therefore considered unusable.As a result of research, the butterfly valve according to the present invention has solved this drawback and is capable of sealing the above-mentioned leaks. The water prevents air from entering, thereby maintaining a vacuum.

As a result, it can be applied to water supply pump turbine exhaust valves of thermal power plants, nuclear power plants, and other turbine plants, allowing the device to fully perform its functions even at high temperatures (for example, 100° C. or higher).

Sealing water uses low pressure (below IKg/am') to avoid erosion of the seat surface due to water sealing.In addition to the above, products that apply this include low pressure bleed air and large diameter butterfly valve seats. This extends to stickers.

Next, the structure of the butterfly valve according to the present invention will be explained with reference to the drawings.

FIG. 1 is a sectional view of the device.

FIG. 2 is a view taken from the field-■ arrow in FIG. 1. (A indicates the drive side).

FIG. 3 is an enlarged view of the dashed-dotted line in FIG. 1, and FIG. 4 is an enlarged view of the dashed-dotted line in FIG.

The valve of this device has a butterfly-type rotating (90°) valve structure with a disk structure in which a valve shaft 3 and a valve body 2 are integrated inside a valve body 1.

5 is a seal moisture pipe, which is provided around the circumference of the valve body;
A seat ring 4 is attached around it. (FIG. 1) A groove 9 is cut in the center of the seat ring in the circumferential direction, and an appropriate number of drilled holes 8 are radially opened between the groove and the seal moisture pipe to communicate with the seal moisture pipe. (Fig. 3) The seal moisture pipe 5 is welded at the shaft end 7 of the valve body 2 and divided into two circumferences and two halves. (Fig. 4) Seal water is injected from the shaft end into the central hole 10 of the valve shaft 3 inserted into the sleeve 6.
The water is led to the seal moisture pipe 5 through the water injection hole 11, and is injected into the seat ring.

The valve body side 1 and the seat portion 12 of the seat ring 4 are in contact with each other while forming a suitable inclined surface. Also, the seat surface has been changed from rubber to metal.

The functions of the two devices having such a structure will be described.

Therefore, seal water is injected from the shaft end 7, and the seal water is injected from the seat ring 4 from the center of the seat surface to the vacuum side, the atmosphere side,
By causing leakage water to spout (leak out) from each, it serves to prevent air from leaking in from the outside atmosphere side.

The result is 0 according to the device.

(1) Since a highly heat-resistant metal sheet is used, conventional devices that can be used at low temperatures of, for example, 80V or less can now be used up to high temperatures (100V or higher); (2)
On the other hand, we took countermeasures against sheet leakage, which is the weak point of metal sheets, by sealing them with water.
) It has various effects such as high durability.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of this device, Figure 2 Figure 1 1: Valve Body 2: Valve body 3: Valve Shaft 4: Seat ring 5: Seal moisture pipe 6: Sleeve 8: Drill Hole 9: Groove IO: Seal water inlet 12: Seat department sub-agent Takuji Kawakami

Claims (1)

[Claims] When installing a seal water pipe around the circumference of the valve disc side or valve seat side, the water injection channel connected from the seal water pipe to the seat ring can be sealed evenly to the valve seat using radial cut holes to the seal water pipe. A butterfly valve characterized by preventing leakage.