JPH085281Y2 - Steam control valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a steam control valve applied to, for example, a steam pipe of a boiler.

[Conventional technology]

FIG. 5 is a structural explanatory view of a conventional large-scale steam control valve. In the figure, steam 1 flowing in a steam pipe (not shown)
The flow rate is controlled by the plug 2 which is opened and closed by being guided by the muffler 3. Reference numeral 4 is a valve rod for opening and closing the plug 2, and 5 is a valve body.

[Problems to be solved by the device]

As described above, in the conventional steam control valve, the plug 2
Open and close to adjust the flow rate of steam 1.
When the valve is slightly opened, steam flows violently through the gap between the tip of the muffler 3 and the annular groove 6 provided in the valve body 5, causing the valve body 5 to vibrate and cause noise and damage.

[Means for solving the problem]

The steam control valve according to the present invention is intended to solve the above-mentioned problems, and in a steam control valve in which a plug is opened and closed by being guided in a cylindrical muffler and the flow rate of steam is adjusted by opening and closing the plug, It is characterized in that it is provided with a plurality of seal rings which are fitted in a gap between the tip and an annular groove of the valve body into which the tip is inserted and which are tapered and are fitted in mutually opposite directions.

[Action]

That is, in the steam control valve according to the present invention, a plurality of taper-shaped seal rings that are fitted in opposite directions are fitted in the gap between the tip of the muffler and the annular groove of the valve body,
The seal ring is pressed against the annular groove of the valve body by the pressure of steam from the upstream side of the seal ring, and a wedge effect is generated on the multiple seal rings to press against the tip side surface of the muffler and the side surface of the annular groove. Completely shuts off the steam flowing through the gap between the tip and the annular groove.

〔Example〕

1 to 3 are structural explanatory views of a steam control valve according to an embodiment of the present invention, and FIG. 4 is a functional explanatory view thereof. In the figure, the steam control valve according to the present embodiment is used in a steam pipe of a boiler, and as shown in FIGS. 1 and 2, a plug 2 which is opened and closed by being guided by a muffler 3 is mounted in a valve body 5. The flow rate of the steam 1 flowing in the steam pipe (not shown) is adjusted by the plug 2. A valve rod 4 opens and closes the plug 2. Further, when the plug 2 is in the slightly opened state, the steam 1 flowing from the gap between the tip of the muffler 3 and the annular groove 6 of the valve body 5 into which the tip is inserted.
In order to prevent the flow of the muffler 3, a seal ring is attached to the tip side of the muffler 3, and the tip of the muffler 3 and the annular groove 6 are attached.
It is designed to fit in the gap between. This seal ring is divided into two parts, as shown in Fig. 2 (a),
The outer seal ring 7 and the inner lower seal ring 8 are each cut in a taper shape so that the upper seal ring 7 has a thick end portion directed outwardly of the lower seal ring 8 and the lower seal ring 8 is thick. The end portions are in contact with the valve body 5 and are fitted downward in mutually opposite directions, and the upper and lower seal rings 7, 7 are pressed by the pressure of the steam 1 from the upstream of the seal ring.
A wedge effect is generated between the 8 and the upper and lower seal rings 7 and 8 so that they are in close contact with each other. A notch 9 is provided on the outer side of the tip of the muffler 3 so that the seal ring does not float up and escape when the pressure difference between the steam 1 upstream and downstream of the seal ring is extremely small. The notch 9 is provided in such a size that the seal ring does not come out of the muffler 3.

When the muffler 3 is assembled into the valve body 5, a seal ring is attached to the tip end side of the muffler 3 as shown in FIG. 3, and the muffler 3 is inserted into the valve body 5 from above without any problem. The muffler 3 is smoothly incorporated into the valve body 5. As shown in FIG. 4 (a), the seal ring not only generates a pressing force P against the gap due to the steam pressure P, but also makes the upper and lower seal rings 7 and 8 tapered with an angle α. Can be applied by increasing the pressing force N = P / sin α. For example, by setting the angle α to 5 to 10 °, the pressing force increases 5 to 10 times. The material may be the same as that of the seal ring used for general plugs and the like. Therefore, the pressure of steam is increased by the upper seal ring 7.
Sufficient sealing performance is obtained by the downward pressing force received on the upper surface of the muffler and the force toward the center of the muffler 3 generated by the wedge effect, and the flow from the gap between the tip of the muffler 3 and the annular groove 6 is completely obtained. It is designed to shut off.

FIG. 4 (b) is a graph showing the result of confirming the effect of the test when the seal ring is attached to the tip side of the muffler 3, the vibration level of the muffler when the seal ring is attached is shown by a dotted line, and the seal level is also shown. The solid line shows the vibration level when the ring is not attached. As shown in the figure,
When the seal ring is not attached, the vibration and noise increase when the plug is in the slightly opened state, but when the seal ring is attached, the vibration and noise are significantly reduced. This test was conducted by applying actual pressure and actual temperature steam to the model valve corresponding to the actual steam control valve.

The steam control valve according to the present invention is not limited to the above embodiment, and the seal ring may be separated into two or more.

[Effect of device]

The steam control valve according to the present invention is configured as described above, and since the plurality of seal rings completely shut off the steam flowing through the gap between the tip of the muffler and the annular groove of the valve body, the valve body does not vibrate and noisy. And no damage.

[Brief description of drawings]

FIG. 1 is a sectional view of a steam control valve according to an embodiment of the present invention,
FIG. 2 is a detailed view of essential parts, FIG. 3 is a perspective view of the disassembled and assembled assembly, FIG. 4 is an explanatory view of its operation, and FIG. 5 is a sectional view of a conventional steam control valve. 1 ... Steam, 2 ... Plug, 3 ... Muffler, 4 ... Valve rod, 5 ...
Valve body, 6 ... annular groove, 7 ... upper seal ring, 8 ... lower seal ring, 9 ... notch.

Claims (1)

[Scope of utility model registration request] 1. A steam control valve in which a plug is opened and closed by being guided in a cylindrical muffler to adjust the flow rate of steam by opening and closing the plug, and a tip of the muffler and an annular groove of a valve body into which the tip is inserted. A steam control valve, which is provided with a plurality of seal rings which are fitted in a gap between and which are tapered to be fitted in mutually opposite directions.