JP4717249B2 - Disc type steam trap - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disk-type steam trap that automatically discharges condensate generated in various steam-using devices and steam pipes by using a valve disk that opens and closes in response to a pressure change in a variable pressure chamber, that is, a thermodynamic steam chamber. In particular, the present invention relates to a high temperature and high pressure steam system (generally 16 kg / cm 2 in a steam trap, 220 ° C. or more).
[0002]
The basic configuration of the disc 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 outlet hole is formed in the center of the variable pressure chamber so that the inlet and the variable pressure chamber communicate with each other. An annular groove that opens to the outer periphery of the ejection hole is provided, an inner ring valve seat is formed between the ejection hole and the annular groove, and an outer ring valve seat that is flush with the inner ring valve seat is formed on the outer periphery of the annular groove. , A discharge hole is provided in the annular groove, the transformation chamber communicates with the outlet, and a disk-shaped valve disk that is attached to and detached from the inner ring valve seat and the outer ring valve seat is disposed in the transformation chamber. It is controlled in a self-powered manner by pressure change and is seated on the inner ring valve seat and the outer ring valve seat, and the condensate is automatically discharged. When this disk-type steam trap is used in a high-temperature and high-pressure steam system, there is a problem that a slight gap is formed between the valve disk and the inner ring valve seat, and the steam leaks. This is because when the valve is closed, a high-temperature and high-pressure inlet-side pressure acts at the center of the bottom surface of the valve disk, and the pressure of the variable pressure chamber acts on the top surface of the valve disk, so that the valve disk curves upwardly, This is because a slight gap is formed between the outer ring valve seat and the inner ring valve seat.
[0003]
[Prior art]
Therefore, conventionally, a technique as disclosed in Japanese Patent Publication No. 48-30416 has been used. This is because an auxiliary valve disc that is attached to and detached from the inner ring valve seat is fitted in the center of the lower surface of the valve disc, so that when the valve is closed, the valve disc is curved upward and a slight gap is formed between the valve disc and the inner ring valve seat. Even if it occurs, the auxiliary valve disk is curved downward and can be in close contact with the inner ring valve seat.
[0004]
[Problems to be solved by the invention]
In the conventional disc type steam trap, the valve disc can be in close contact with the outer ring valve seat immediately after the valve is closed, and the auxiliary valve disc can be in close contact with the inner ring valve seat. Therefore, there is a problem that the fluid in the variable pressure chamber is discharged to the outlet and the valve is opened 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 injection hole communicating with the inlet, and the decrease in the degree of curvature of the valve disk is larger than the decrease in the degree of curvature of the auxiliary valve disk. The auxiliary valve disc and the inner ring valve seat are in close contact with each other, but a slight gap is formed between the valve disc and the outer ring valve seat. Therefore, the technical problem of the present invention is to provide a disc type steam trap which does not discharge the fluid in the variable pressure chamber until the auxiliary valve disc is separated from the inner ring valve seat.
[0005]
[Means for Solving the Problems]
The technical means of the present invention devised to solve the above technical problem is that a lid is fixed to a main body having an inlet and an outlet to form a variable pressure chamber therein, and an ejection hole that opens at the center of the variable pressure chamber An annular groove that opens to the outer periphery of the ejection hole is provided to communicate the inlet and the variable pressure chamber, and an inner ring valve seat is formed between the ejection hole and the annular groove. The outer ring valve seat is formed in the same plane as the outer ring, a discharge hole is provided through the annular groove, the variable pressure chamber communicates with the outlet, and a disc-shaped valve disk that is attached to and detached from the inner ring valve seat and the outer ring valve seat is disposed in the variable pressure chamber. An auxiliary valve disc that is attached to and detached from the inner ring valve seat is fitted in the center of the bottom surface of the valve disc, and a seal ring that slides on the outer peripheral wall of the annular groove is disposed in the annular groove, and the upper end of the seal ring is opened when the valve disc is opened. the spring as an elastic member for slightly protruded than the inner valve seat and the outer ring valve seat , In which it provided between the lower surface of the bottom wall and the seal ring of the annular groove.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, an auxiliary valve disc that is attached to and detached from an inner ring valve seat is fitted in the center of the lower surface of the valve disc, and a seal ring that slides on the outer peripheral wall of the annular groove is disposed in the annular groove. A spring as an elastic member is provided between the bottom wall of the annular groove and the lower surface of the seal ring so that the upper end slightly protrudes from the inner ring valve seat and the outer ring valve seat. Therefore, immediately after the valve is closed, the valve disk is in close contact with the outer ring valve seat and the seal ring against the biasing force of the spring as an elastic member , and the auxiliary valve disk is in close contact with the inner ring valve seat. If a slight gap is created between the valve disc and the outer ring valve seat due to the pressure drop in the variable pressure chamber, the seal ring maintains close contact with the valve disc by the biasing force of the spring as an elastic member , and the fluid in the variable pressure chamber is discharged. do not do. Then, after the pressure in the variable pressure chamber decreases to a predetermined valve opening pressure, the valve disk and the auxiliary valve disk are separated from the seal ring and the inner ring valve seat and opened.
[0007]
【Example】
An embodiment showing a specific example of the above technical means will be described (see FIG. 1).
A lid 2 is screwed to the main body 1 to form a variable pressure chamber 3 therein. An inlet 4 and an outlet 5 are formed on the main body 1 on substantially the same axis. The main body 1 is provided with a jet hole 6 that opens at the center of the variable pressure chamber 3, and the inlet 4 and the variable pressure chamber 3 are communicated with each other through the jet hole 6. An annular groove 8 is provided around the outer periphery of the ejection hole 6, an annular inner ring valve seat 9 is formed between the ejection hole 6 and the annular groove 8, and the inner ring valve seat 9 is concentrically identical to the outer periphery of the annular groove 8. A planar annular outer ring valve seat 10 is formed. The end of the annular groove 8 communicates with the outlet 5 through the discharge hole 7. A disc-shaped valve disk 11 that opens and closes to the inner ring valve seat 9 and the outer ring valve seat 10 to open and close is disposed in the variable pressure chamber 3 in a free state. The valve disc 11 is fitted with an auxiliary valve disc 14 that is attached to and detached from the inner ring valve seat 9 at the center of the lower surface.
[0008]
A seal ring 12 that slides on the outer peripheral wall of the annular groove 8 is disposed in the annular groove 8, and the upper end of the seal ring 12 is opened 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 slightly protrudes from the inner ring valve seat 9 and the outer ring valve seat 10. The seal ring 12 maintains close contact with the valve disk 11 by the biasing force of the wave spring 13 when a slight gap is generated between the valve disk 11 and the outer ring valve seat 10 due to a pressure drop in the variable pressure chamber.
[0009]
Next, the operation will be described. When the steam does not stay in the variable pressure chamber 3, the valve disk 11 and the auxiliary valve disk 14 have the outer ring valve seat 10, the seal ring 12, and the inner ring valve seat owing to the fluid pressure on the inlet 4 side acting via the ejection hole 6. The low-temperature condensate is separated from 9 and discharged to the outlet 5 through the annular groove 8 and the discharge hole 7.
[0010]
When the condensate is discharged and steam flows into the variable pressure chamber 3, the pressure in the variable pressure chamber 3 rises, and high-speed steam flows down the lower surfaces of the valve disk 11 and the auxiliary valve disk 14 to static pressure. Due to the lowering, the valve disk 11 is seated on the outer ring valve seat 10 and the seal ring 12 against the biasing force of the wave spring 13, and the auxiliary valve disk 14 is seated on the inner ring valve seat 9 and is closed.
[0011]
When the steam in the variable pressure chamber 3 condenses due to heat dissipation or the like and the steam pressure decreases, the valve disk 11 creates a slight gap with the outer ring valve seat 10 as shown in FIG. However, the urging force of the wave spring 13 maintains close contact with the valve disk 11 and does not discharge the fluid in the variable pressure chamber 3. Then, after the pressure in the variable pressure chamber 3 is lowered to a predetermined valve opening pressure, the valve disk 11 and the auxiliary valve disk 14 are separated from the seal ring 12 and the inner ring valve seat 9 and are opened. The above open / close valve cycle is repeated.
[0012]
【The invention's effect】
As described above, according to the present invention, even if a slight gap is generated between the valve disk and the outer ring valve seat, the seal ring maintains close contact with the valve disk and does not discharge the fluid in the variable pressure chamber. It is possible to prevent the valve from opening. Therefore, an excellent effect is obtained that frequent open / close valves can be prevented and the life can be extended.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an embodiment of a disc type steam trap of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Main body 2 Lid 3 Transformer chamber 4 Inlet 5 Outlet 6 Ejection 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 14 Auxiliary valve disk

Claims (1)

A lid is fixed to the main body having an inlet and an outlet to form a variable pressure chamber inside, and an injection hole that opens at the center of the variable pressure chamber is provided so that the inlet and the variable pressure chamber communicate with each other. A groove is provided 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 is formed around the outer periphery of the annular groove. An auxiliary valve disc that is attached to and detached from the inner ring valve seat is located in the center of the bottom surface of the valve disc. A seal ring that slides on the outer peripheral wall of the annular groove is disposed in the annular groove, and a spring as an elastic member that slightly protrudes the upper end of the seal ring from the inner ring valve seat and the outer ring valve seat when the valve disk is opened. , characterized in that provided between the lower surface of the bottom wall and the seal ring of the annular groove Disc type steam traps.

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