JP2002310396A - Disk type steam trap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk type steam trap which does not discharge any fluid in a variable pressure chamber until a valve disk is separated from an inner ring valve seat. SOLUTION: The variable pressure chamber 3 is formed by fixing a lid body 2 to a body 1 having an inlet 4 and an outlet 5. A spray hole 6 opened at the center of the variable pressure chamber 3 is made to communicate the inlet 4 with the variable pressure chamber 3. An annular groove 8 is formed in the outer circumference of the spray hole to form an inner ring valve seat 9 between the spray hole 6 and the annular groove 8 and to form an outer ring valve seat 10 on the outer circumference of the annular groove 8. The inner ring valve seat 9 is formed of a metal of the coefficient of thermal expansion larger than that of the outer ring valve seat 10, and joined with the body 1. The annular groove 8 is communicated with outlet 5. A disk-like valve disk 11 which is attached/detached to/from the inner ring valve seat 9 and the outer ring valve seat 10 to open a valve is disposed in the variable pressure chamber 3 in a free moving state. A seal ring 12 which is slidably moved on an outer circumferential wall of the annular groove 8 is disposed, and a ring-like corrugated spring 13 to slightly protrude an upper end of the seal ring 12 from the outer ring valve seat 10 when the valve disk 11 is opened is disposed between a bottom wall of the annular groove 8 and a lower side of the seal ring 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a valve disc which opens and closes in response to a pressure change in a transformer chamber, that is, a thermodynamic steam chamber, to automatically condense water generated in various steam-using devices and steam pipes. The present invention relates to a disc type steam trap discharged to a steam trap, particularly to a steam trap having a high temperature and a high pressure (generally, a steam trap having a pressure of 16 kg / cm 2 and 220 ° C. or more).

The basic structure of a disk type steam trap is that a lid is fixed to a main body having an inlet and an outlet to form a variable pressure chamber inside, and an ejection hole opened at the center of the variable pressure chamber is provided to form an inlet and a variable pressure chamber. And an annular groove that opens around the outer periphery of the ejection hole to form an inner ring valve seat between the ejection hole and the annular groove, and an outer ring valve seat that is flush with the inner ring valve seat around the outer periphery of the annular groove. Is formed, a discharge hole is provided from the annular groove to communicate the variable pressure chamber and the outlet, and a disc-shaped valve disk that is separated from and seated on the inner ring valve seat and the outer ring valve seat is disposed in the variable pressure chamber. The self-powered control is performed by the pressure change in the variable pressure chamber, and the condensate is automatically discharged by allowing the inner ring valve seat and the outer ring valve seat to be separated and seated. When this disc-type steam trap is used in a high-temperature, high-pressure steam system, there is a problem that a slight gap is formed between the valve disc and the inner ring valve seat, and steam leaks. This is because when the valve is closed, the inlet side pressure of the high temperature and high pressure acts on the center of the lower surface of the valve disk, and the pressure of the variable pressure chamber acts on the upper surface of the valve disk. This is because a small gap is formed between the outer ring valve seat and the inner ring valve seat.

[0003]

2. Description of the Related Art Conventionally, a technique as shown in Japanese Patent Publication No. 59-7078 has been used. This is because the inner and outer ring valve seats are formed of dissimilar metals so that the thermal expansion of the inner ring valve seats is greater than that of the outer ring valve seats, and the inner ring valve seats are made higher in expansion and higher than the outer ring valve seats to close. Even when the valve disc curves upwardly convex when the valve is opened, the valve disc can be in close contact with the inner ring valve seat and the outer ring valve seat.

[0004]

In the above-mentioned conventional disk-type steam trap, the close contact between the valve disk and the inner ring valve seat and the outer ring valve seat can be maintained immediately after the valve is closed. Since a slight gap is formed between the valve seat and the valve disk, there is a problem that the fluid in the variable pressure chamber is discharged to the outlet and opens relatively early. This is because the pressure drop in the variable pressure chamber, which is shut off from the inlet, is faster than the temperature drop in the outlet hole communicating with the inlet, and the degree of curvature of the valve disk is greater than the degree of thermal expansion of the inner ring valve seat. In addition, the valve disk is in close contact with the inner ring valve seat, but creates a slight gap between the valve disk and the outer ring valve seat. Accordingly, it is an object of the present invention to provide a disk-type steam trap which does not discharge the fluid in the variable pressure chamber until the valve disk is separated from the inner ring valve seat.

[0005]

Means for Solving the Problems The technical means of the present invention taken to solve the above technical problem is to fix a lid body to a main body having an inlet and an outlet to form a variable pressure chamber therein, An ejection hole that opens at the center of the transformation chamber is provided to communicate the inlet with the transformation chamber, and an annular groove that opens around the outside of the ejection hole is provided, and an inner ring valve seat is formed between the ejection hole and the annular groove, An outer ring valve seat is formed around the outer periphery of the annular groove, a discharge hole is provided from the annular groove to communicate the variable pressure chamber and the outlet, and a disk-shaped valve disk that separates and seats on the inner ring valve seat and the outer ring valve seat is provided in the variable pressure chamber. In the arrangement, the inner and outer ring valve seats are formed of dissimilar metals so that the thermal expansion of the inner ring valve seat is larger than that of the outer ring valve seat, and a seal ring that slides on the outer peripheral wall of the annular groove is arranged in the annular groove. When the valve disc is opened, an elastic member that makes the upper end of the seal ring slightly project from the outer ring valve seat Those digits.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, the inner and outer ring valve seats are formed of different metals so that the thermal expansion of the inner ring valve seat is larger than that of the outer ring valve seat, and the outer peripheral wall of the annular groove slides in the annular groove. And a resilient member for slightly projecting the upper end of the seal ring from the outer ring valve seat when the valve disk is opened. Therefore, immediately after the valve is closed, the valve disc is in close contact with the inner ring valve seat, the outer ring valve seat, and the seal ring against the urging force of the elastic member. When a small gap is created between the valve disk and the outer ring valve seat due to the pressure drop in the variable pressure chamber, the seal ring maintains the close contact with the valve disk by the biasing force of the elastic member, and does not discharge the fluid in the variable pressure chamber. Then, after the pressure in the variable pressure chamber has decreased to a predetermined valve opening pressure, the valve disc separates from the inner ring valve seat and the seal ring and opens.

[0007]

An embodiment showing a specific example of the above technical means will be described (see FIG. 1). A transformer 2 is formed by screwing a lid 2 to the main body 1. An inlet 4 and an outlet 5 are formed on the main body 1 on substantially the same axis. An ejection hole 6 opening at the center of the transformation chamber 3 is opened in the main body 1, and the inlet 4 and the transformation chamber 3 are communicated via the ejection hole 6. An annular groove 8 is provided around the outside of the ejection hole 6,
An annular inner ring valve seat 9 is formed between the ejection hole 6 and the annular groove 8,
The inner ring valve seat 9 is formed concentrically with the inner ring valve seat 9 around the outer periphery of the annular groove 8.
An annular outer ring valve seat 10 is formed which is slightly lower than that. The outer ring valve seat 10 is formed integrally with the main body 1, and the inner ring valve seat 9 is formed of a metal having a larger coefficient of thermal expansion than the outer ring valve seat 10 and is joined to the main body 1. The inner ring valve seat 9 is formed integrally with the main body 1 and the outer ring valve seat 1 is formed.
0 may be formed of a metal having a smaller coefficient of thermal expansion than the inner ring valve seat 9 and joined to the main body 1. Further, the inner ring valve seat 9 and the outer ring valve seat 1 formed of a metal having a smaller coefficient of thermal expansion than the inner ring valve seat 9.
0 may be formed separately from the main body 1 and joined to the main body 1 respectively. The end of the annular groove 8 communicates with the outlet 5 through the discharge hole 7. A disc-shaped valve disk 11 that is detachably seated on the inner ring valve seat 9 and the outer ring valve seat 10 to open and close the valve is disposed in the variable pressure chamber 3 in a free state.

A seal ring 12 sliding on the outer peripheral wall of the annular groove 8 is disposed in the annular groove 8, and a seal ring is provided between the bottom wall of the annular groove 8 and the lower surface of the seal ring 12 when the valve disk 11 is opened. A ring-shaped wave spring 13 is disposed as an elastic member that protrudes the upper end of 12 slightly from the outer ring valve seat 10. The seal ring 12 maintains the close contact with the valve disk 11 by the urging force of the wave spring 13 when a small gap is generated between the valve disk 11 and the outer ring valve seat 10 due to the pressure drop in the variable pressure chamber.

Next, the operation will be described. When no steam is retained in the transformation chamber 3, the valve disc 11
The fluid pressure at the inlet 4 acting on the valve disc 11
Is separated from the inner and outer ring valve seats 9 and 10 to condense low-temperature condensate
To the outlet 5 through the discharge hole 7.

When the condensate is discharged and steam flows into the variable pressure chamber 3, the pressure in the variable pressure chamber 3 increases, and high-speed steam flows down the lower surface of the valve disk 11 to reduce the static pressure. As a result, the valve disc 11 is seated on the inner ring valve seat 9, the outer ring valve seat 10, and the seal ring 12 against the urging force of the wave spring 13, and is closed.

When the steam in the variable pressure chamber 3 is condensed by heat radiation or the like and the steam pressure decreases, the valve disk 11 has a slight gap between the valve disk 11 and the outer ring valve seat 10 as shown in FIG. The seal ring 12 maintains the close contact with the valve disk 11 by the urging force of the wave spring 13 and does not discharge the fluid in the variable pressure chamber 3. Then, after the pressure in the variable pressure chamber 3 decreases to a predetermined valve opening pressure, the valve disc 11 separates from the inner ring valve seat 9 and the seal ring 12 and opens. The above-described on-off valve cycle is repeated.

[0012]

As described above, according to the present invention, even if a slight gap is formed between the valve disc and the outer ring valve seat, the seal ring maintains the close contact with the valve disc and discharges the fluid in the variable pressure chamber. As a result, opening the valve early can be prevented. Therefore, there is an excellent effect that frequent on-off valves can be prevented and the life can be extended.

[Brief description of the drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Lid 3 Transformation chamber 4 Inlet 5 Outlet 6 Injection hole 7 Discharge hole 8 Annular groove 9 Inner ring valve seat 10 Outer ring valve seat 11 Valve disk 12 Seal ring 13 Wave spring

Claims (1)

[Claims] 1. A variable pressure chamber is formed by fixing a lid to a main body having an inlet and an outlet, and a discharge hole is provided at the center of the variable pressure chamber to communicate the inlet with the variable pressure chamber. By providing an annular groove that opens around the periphery, forming an inner ring valve seat between the ejection hole and the annular groove, forming an outer ring valve seat around the outer periphery of the annular groove, providing a discharge hole from the annular groove, and Through the exit,
In the case where a disc-shaped valve disc which is separated and seated on the inner ring valve seat and the outer ring valve seat is arranged in the variable pressure chamber, the inner and outer ring valve seats are made of different metals so that the thermal expansion of the inner ring valve seat is larger than that of the outer ring valve seat. A seal ring that slides on the outer peripheral wall of the annular groove is disposed in the annular groove, and an elastic member is provided that causes the upper end of the seal ring to slightly project from the outer ring valve seat when the valve disc is opened. Disc type steam trap.