JP3030531B2 - Float valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes a specific gravity difference between a gas and a liquid to drive a valve means with an open or closed float to automatically discharge one fluid from a gas-liquid mixture system. The present invention relates to a structure of a float valve.

This float valve is used for selectively and automatically discharging either gas or liquid from a system in which gas and liquid are mixed, and automatically controls condensate generated in a steam piping system. A steam trap, an air trap that automatically discharges condensed water generated in the compressed air piping system,
It is used as an air vent for automatically discharging air mixed in the water piping system.

In the float valve, the float floating on the liquid surface moves up and down together with the liquid surface in balance with the buoyancy and its own weight, thereby driving the valve means to open and close the valve hole formed in the valve seat member. Therefore, the openable and closable valve hole area is limited, and the valve chamber side is formed as a small-diameter hole having a relatively small diameter.

[0004]

2. Description of the Related Art A float valve having a valve seat structure as described above is disclosed, for example, in Japanese Patent Publication No. 59-32718. The float valve disclosed herein is a free-float type trap, and as understood from the publication, a small-diameter hole on the valve chamber side and a large-diameter hole having a larger cross-sectional area than the small-diameter hole downstream thereof. The valve seat member having a valve hole made of stainless steel which is a metal material harder than the valve casing in consideration of wear resistance. In addition, it has been conventionally performed to perform a quenching process on the valve seat member to further improve the hardness.

[0005]

However, in the above-mentioned conventional apparatus, there is a problem that the flow area of the small-diameter hole is reduced in a relatively short time and a desired discharge flow rate cannot be obtained. This is because foreign substances such as iron powder and carbon mixed in the discharged fluid adhere to and accumulate in the small-diameter holes. That is, the valve seat member made of stainless steel is attached.
Rust is generated and the surface becomes rough.
Foreign matter accumulates with this adhesion as a nucleus.
To do so. Also, a valve made of stainless steel
Since the seat member has relatively low hardness, it flows down the small-diameter hole at high speed.
Iron powder etc. penetrates the surface of the small diameter hole and gradually accumulates
It is to go.

Accordingly, an object of the present invention is to provide a float valve in which foreign matter does not adhere to a small diameter hole of a valve hole.

[0007]

In order to solve the above-mentioned technical problems, the technical means of the present invention is to form an inlet, a valve chamber and an outlet by valve casing, and to form a small-diameter hole in the valve chamber side. A valve seat having a valve hole having a valve hole communicates the valve chamber to the outlet side, and the valve means is driven by a float disposed in the valve chamber to open and close the valve chamber side opening end of the small diameter hole. In the valve, at least a portion of the valve seat member that forms the small-diameter hole is made of a ceramic material.

As the above ceramic material, alumina, silicon nitride, zirconia and the like can be used.

[0009]

The operation of the above technical means is as follows.
Since the portion of the valve seat member forming the small diameter hole is made of a ceramic material, it does not rust.
And therefore the surface does not become rough. Therefore, the small hole table
Iron powder or the like does not adhere to the surface, and the foreign matter flows downstream along with the discharged fluid flowing down at a high speed . In addition,
Metal material has high hardness, so iron powder etc.
Exhaust flow that does not stick and foreign matter flows down at high speed
Flows downstream with the body.

[0010]

An embodiment showing a specific example of the above technical means will be described (see FIG. 1). This embodiment is applied to a free float type steam trap. Lid member 2 on body 1
Are fastened with bolts 3 to form a valve casing, and a valve chamber 4 is formed therein. An inlet 5 and an outlet 6 are coaxially opened in the upper part of the main body 1. The inlet 5 communicates with the valve chamber 4 via a cylindrical screen 7. The outlet 6 communicates with the valve chamber 4 via a valve seat member 8 described below.

A valve seat member 8 is attached to the lower side wall of the main body 1 by screw connection. The valve seat member 8 includes a base 9 screwed to the main body 1 and a tip 10 attached to the tip of the base 9 by shrink fitting. The base 9 is made of stainless steel, and the tip 10 is made of a ceramic material. The valve seat member 8 is provided with a valve hole 11 for communicating the valve chamber 4 with the outlet 6 side. The valve hole 11 includes a large-diameter hole 12 formed in the base portion 9, a through hole 13 for connecting the large-diameter hole 12 to the outlet 6 side, a small-diameter hole 14 formed in the distal end portion 10 on the valve chamber 4 side, and A taper hole 15 is provided to allow the small diameter hole 14 to communicate with the large diameter hole 12 of the base 9.

A hollow spherical float 16 is disposed in the valve chamber 4 in a free state. At the bottom of the valve chamber 4, there is formed a float seat 17 for determining the lowering position of the float 16.

The condensate flowing from the inlet 5 accumulates in the valve chamber 4,
The float 17 floats up and down according to the liquid level to open and close the end of the small diameter hole 14 on the valve chamber 4 side. As a result, the condensate in the valve chamber 4 is discharged from the valve hole 11 to the outlet 6. The tip 10 made of a ceramic material does not rust and the surface of the small-diameter hole 14 is rough.
As a result, iron powder and the like do not adhere, and the foreign matter flows out to the outlet 6 together with the discharged fluid flowing down at a high speed . Ma
In addition, since ceramic materials have high hardness, iron powder etc. are small.
The foreign matter does not pierce the surface of the diameter hole 14 and the foreign matter is at a high speed.
With the discharged fluid flowing down to the downstream side.

In the above-described embodiment, the base portion and the front end portion of the valve seat member are joined by shrink fitting.
The connection may be made by screw connection or other means. In addition, although only the tip portion of the valve seat member is made of a ceramic material, it is needless to say that the entire valve seat member may be made of a ceramic material.

[0015]

The present invention has the following specific effects. According to the present invention as described above, since no adhesion accumulation of debris Ru by <br/> to Chakusabi occurs in the portion for forming the small diameter hole of the valve seat member is made from ceramic material ing Thus, a float valve capable of maintaining a good initial discharge action for a long period of time without a decrease in discharge flow rate can be obtained. Also, since the ceramic material has high hardness, iron powder etc.
It does not pierce the surface, and this also prevents foreign matter from adhering and depositing in the small-diameter hole. Furthermore, since the ceramic material has high hardness, the valve chamber side end of the small-diameter hole can be prevented from being worn even when the valve means is frequently detached and seated, and the initial good sealing action is maintained for a long period of time. A float valve that can be obtained is obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a free-float type steam trap according to an embodiment of a float valve of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Lid member 4 Valve chamber 5 Inlet 6 Outlet 8 Valve seat member 9 Base part 10 Tip part 11 Valve hole 12 Large diameter hole 14 Small diameter hole 16 Float

Claims (1)

(57) [Claims] An inlet, a valve chamber and an outlet are formed by valve casing, and the valve chamber is communicated with the outlet side by a valve seat member having a valve hole having a small diameter hole on the valve chamber side. The valve means is driven by the arranged float to open and close the valve chamber side opening end of the small diameter hole, wherein at least a portion of the valve seat member forming the small diameter hole is made of a ceramic material. valve.