JPH0740798Y2 - Steam trap - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention provides a steam trap, particularly a steam trap device for a flow path opening / closing valve that opens and closes a direct flow path between an inlet and an outlet in a steam trap housing. The present invention relates to a steam trap which is also used as a bypass valve and also serves as a bypass valve, and more particularly to a fixing means for the valve seat and the valve seat packing.

<Prior Art> Generally, a steam trap is used for a pipe end of a piping system, etc., and a structure of a conventional steam trap also serving as a bypass valve is shown in FIG.

As shown in the figure, the conventional steam trap has a steam trap device 13 installed in a valve seat 6 provided in the middle of a direct flow passage A between an inlet 2 and an outlet 3 in a steam trap housing 1. The passage opening / closing valve unit 5 is mounted so as to be detachable from the seat, the inflow hole 11 is formed in the passage opening / closing valve unit 5, and the valve seat packing 16 is mounted on the valve seat 6 to open and close the passage. Handle screw shaft 14 that can come into contact with the upper part of valve unit 5
The flow passage opening / closing valve unit 5 is forced to the seated position by the screwing operation of the handle screw shaft 14 to function as a steam trap, and the handle screw shaft 14 is unscrewed to open the flow passage opening / closing valve unit 5. It is configured so that it receives the pressure of the fluid acting from the inlet 2 side and separates from it to function as a bypass valve.

<Problems to be solved by the invention> In the steam trap shown in Fig. 3, in order to improve the sealing property, a tightening body B made of a screw is used for a valve seat made of a soft sealing material such as tetrafluoroethylene resin. Patkin 16
And the valve seat 6 are brought into contact with each other for sealing.

However, due to the nature of the soft seal material of the valve seat packing 16, creep development due to heat called cold flow occurs and plastic deformation occurs. In the first place, the soft seal material has a very small coefficient of friction and is often used to reduce sliding resistance. Therefore, once cold flow occurs, the tightening force of the tightening body B is extremely reduced, and the valve seat Positioning of the packing pad 16 is made difficult.

Therefore, in order to maintain the tightening force of the tightening body B,
As shown in FIG. 5, the tightening body B is screwed into the inflow hole 11 of the passage opening / closing valve unit 5, while the spring C is incorporated in the valve body 7, and the reaction force is used to tighten the tightening force of the tightening body B. Is maintained. At this time, the valve seat packing 16 is sandwiched between the valve body 7 and the tightening body B of the passage opening / closing valve unit 5.

According to this method as well, when the creep development of the packing 16 progresses and the frictional force between the packing 16 and the tightening body B becomes extremely small, the valve body 7 repeats the separation and seating. Then, the tightening body B becomes loose, and the packing 16 is dropped from the valve body 7, or the falling of the tightening body B causes a misalignment, resulting in valve leakage.

In view of the above, the present invention guarantees that the valve seat packing is fixed to the valve seat even if the valve seat packing is plastically deformed, and that the centering of the flow path opening / closing valve unit is constantly guaranteed to prevent the valve body from falling off. An object of the present invention is to provide a steam trap capable of eliminating valve leakage due to misalignment.

<Means for Solving the Problem> The means for solving the problem according to the present invention is provided in the middle of the direct passage A between the inlet 2 and the outlet 3 in the steam trap housing 1 as shown in FIGS. A flow path opening / closing valve unit 5 having a steam trap device 13 installed therein is mounted on the valve seat 6 so as to be detachable from the valve seat 6, and an inflow hole 11 is bored in the flow path opening / closing valve unit 5 to form an upper portion of the valve seat 6. The valve seat packing 16 is attached to
A handle screw shaft 14 that can come into contact with the upper portion of the flow passage opening / closing valve unit 5 is provided, and the flow passage opening / closing valve unit 5 is forced to a seated position by screwing the handle screw shaft 14, and the handle screw shaft 14 is also provided. In the steam trap configured such that the passage opening / closing valve unit 5 is separated by receiving the pressure of the fluid acting from the inlet 2 side by the screwing back of the passage opening / closing valve unit 5 To the inflow port 2a of A,
A sleeve 17 for guiding the flow path opening / closing valve unit 5 to the valve seat 6 so as to be freely seated / separated is internally provided.
A through hole 18 for communicating with the direct passage A is provided, and a spring 19 is provided to press the sleeve 17 to constantly urge the valve seat 6 and the valve seat packing 16 in a close contact. Is.

<Operation> In the above means for solving the problem, when the steam trap device 13 is operated, the handle screw shaft 14 is screwed in to forcefully seat the flow path opening / closing valve unit 5 and the valve seat packing 16 is opened / closed. Since it is pressed by the seating surface of the valve unit 5 and brought into close contact with the valve seat 6, it does not function as a bypass valve.

On the other hand, when the handle screw shaft 14 is unscrewed, the passage opening / closing valve unit 5 receives the pressure of the fluid initially filled in the inflow port 2a and the spring force of the spring 19 to separate from the direct passage passage. Open A,
The fluid on the inlet 2 side passes through the through hole 19 of the sleeve 17 and the outlet 3
Spill to the side.

Also in this case, since the sleeve 17 is internally provided from the inflow hole 11 of the passage opening / closing valve unit 5 to the inlet 2a, the passage opening / closing valve unit 5 is always centered by the sleeve 17.

Further, since the spring 19 constantly urges the sleeve 17 in a direction in which the valve seat 6 and the valve seat packing 16 are brought into close contact with each other, the sleeve 17 is downwardly moved to the sleeve 17 regardless of the position of the flow path opening / closing valve unit 5. The pressing force of is applied to the valve seat 6 so that the valve seat packing 16
Is fixed.

<Embodiment> An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a longitudinal sectional view of a flow path on-off valve unit in a seated state in a steam trap showing an embodiment of the present invention, and FIG. 2 is a vertical sectional view of a flow path on-off valve unit in a separated state.
The same functional parts as those of the prior art shown in FIGS. 3 and 4 are designated by the same reference numerals.

In FIGS. 1 and 2, 1 is a steam trap housing, 2 is an inlet, 3 is an outlet, 4 is a housing, 5 is a valve element 7 screwed together.
A channel opening / closing valve unit including a cap 8 and a cap 8, and a direct passage A between the inlet 2 and the outlet 3 in a storage chamber formed by the upper body 1a of the housing 1 and the lid 4. In the middle of (Fig. 2), that is, on the valve seat 6 provided between the inflow port 2a and the outflow port 3a, the valve seat 6 is freely detachably seated. The on-off valve unit 5 is composed of a disk valve 10 placed inside a variable pressure chamber 9 formed inside the on-off valve unit 5, and an inflow hole 11 and an outflow hole 12 formed in the valve body 7. A steam trap device 13 is installed.

Reference numeral 14 denotes a screw shaft which is screwed by a handle 15 and is screwed into the lid body 4, and a lower end surface 14b thereof is brought into contact with a recess 8a formed on the upper surface of the cap 8 of the on-off valve unit 5. ing.

Reference numeral 16 is a valve seat packing for improving the sealing performance between the lower end surface of the flow path opening / closing valve unit 5, that is, the seating surface of the valve body 7 and the seating surface of the valve seat 6, and is made of a soft material such as tetrafluoroethylene resin. It is made of a sealing material and is attached to the upper portion (seat surface) of the valve seat 6.

Reference numeral 17 denotes a sleeve which guides the flow path opening / closing valve unit 5 to and from the valve seat 6 so that the flow path opening / closing valve unit 5 can be freely seated on / off.
It is furnished up to 2a. The sleeve 17 is formed in a hollow cylindrical shape, and is inserted into the inflow hole 11 to guide the passage opening / closing valve unit 5 so as to be freely seated / separated, and is integrally formed with the guide portion 17a. As described above, the guide portion 17a is fitted to the inflow port 2a so that the guide portion 17a can center the flow passage opening / closing valve unit 5 even when the flow passage opening / closing valve unit 5 is in the separated state. Direct passage A when the passage opening / closing valve unit 5 is separated from the portion 17b
And a through hole 18 for communicating with. A pressing piece 17c for pressing the valve seat packing 16 against the valve seat 6 from above is formed at the upper end of the support portion 17b so as to project outward.

Reference numeral 19 is a coil spring that presses the sleeve 17 and constantly urges the valve seat 6 and the valve seat packing 16 in a direction in which the valve seat 6 and the valve seat packing 16 are in close contact with each other (downward). It is mounted on a spring receiving piece 17d which is formed to project inward at the lower end of the. The biasing force of the spring 19 has an initial load, and
As shown in FIG. 2, even when the steam trap device 13 reaches the upper limit (when the direct passage A is fully opened), the load is set to be substantially constant.

In the figure, 20 is a strainer for preventing foreign matter from flowing into the steam trap device 13, 21 is a bimetal ring, and 22 is a
Is a gasket.

In the above-described structure, the handle shaft 15 is swung to screw the screw shaft 14 into the open / close valve unit 5 forcibly so that the valve seat packing 16 is pressed against the seating surface of the valve body 7 so that the valve seat 7 is pressed. When it is brought into close contact with 6, the direct passage A is closed, the steam trap device 13 performs a predetermined trap operation, and does not function as a bypass valve.

On the other hand, when the screw shaft 14 is unscrewed, as shown in FIG. 2, the on-off valve unit 5 detects the pressure of air and condensate on the inlet 2 side, which is filled in the inlet 2a at the time of starting, and the spring force of the spring 19. Upon receiving and floating, the direct passage A is opened and the drain or the like on the inlet 2 side flows out to the outlet 3 side through the conduction hole 18 of the sleeve 17.

At this time, even if the valve seat packing 16 is plastically deformed to some extent in the axial direction, the spring 19 constantly urges the sleeve 17 in a direction to bring the valve seat 6 and the valve seat packing 16 into close contact with each other. Regardless of the position of the flow path opening / closing valve unit 5, a downward pressing force acts on the sleeve 17, and the valve seat 6 of the valve seat packing 16 is always provided.
Is secured to.

Further, since the guide portion 17a of the sleeve 17 that guides the flow path opening / closing valve unit 5 to the valve seat 6 in a detachable manner is inserted into the inflow hole 11, and the support portion 17b is fitted into the inflow port 2a. Centering of the passage opening / closing valve unit 5 is always ensured by the sleeve 17, and valve leakage due to dropout or misalignment of the valve body 7 is eliminated.

Further, since the flow path opening / closing valve unit 5 is constantly centered by the sleeve 17, the deep-seated parts of the steam trap can be replaced without a tool, and the maintainability is improved.

Further, the sleeve 17 is internally provided from the inflow hole 11 to the inflow port 2a in order to center the flow path opening / closing valve unit 5, but the sleeve 17 is provided with a through hole 18 for communicating with the direct flow path A. Therefore, the flow path opening / closing valve unit 5 can be made to function as a bypass valve.

<Effects of the Invention> As is apparent from the above description, according to the present invention, since the spring for constantly biasing the sleeve in the direction of closely contacting the valve seat and the valve seat packing is provided, the valve seat packing is plastic. Even if it is deformed, a downward pressing force acts on the sleeve irrespective of the position of the flow path opening / closing valve unit, so that the fixing of the valve seat packing to the valve seat can always be guaranteed.

In addition, since the sleeve that guides the flow path on-off valve unit to the valve seat in a detachable manner is installed from the inflow hole to the inflow port, centering of the flow path on-off valve unit is always guaranteed by the sleeve, and There will be no valve leakage due to dropout or misalignment.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a flow path opening / closing valve unit in a seated state in a steam trap showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional view of a main part of the flow path opening / closing valve unit in a separated state, and FIG. FIG. 4 is a vertical cross-sectional view of a conventional steam trap, FIG. 4 is a vertical cross-sectional view of a steam trap showing another conventional example, and FIG. 1: Steam trap housing, 2: Inlet, 3: Outlet, 5: Flow passage opening / closing valve unit, 6: Valve seat, 11: Inlet hole, 13: Steam trap device, 14: Handle screw shaft, 16: Valve Seat packing, 17: sleeve, 18: conduction hole, 19: spring, 2a: inlet, A: direct passage.

Claims (1)

[Scope of utility model registration request] 1. A flow path opening / closing valve unit having a steam trap device installed therein is detachably seated on a valve seat provided in the middle of a direct flow path between an inlet and an outlet in a steam trap housing. An inlet hole is bored in the passage opening / closing valve unit, a valve seat packing is mounted on an upper portion of the valve seat, and a handle screw shaft capable of contacting with an upper portion of the passage opening / closing valve unit is provided. The passage opening / closing valve unit is forced to the seated position by the screwing operation of the screw shaft, and the passage opening / closing valve unit is separated by receiving the pressure of the fluid acting from the inlet side by the screwing back of the handle screw shaft. In the steam trap, a sleeve for guiding the passage opening / closing valve unit to the valve seat so as to be detachable from the valve seat is installed from the inflow hole of the passage opening / closing valve unit to the inlet of the direct passage. Directly A steam trap provided with a through hole for communicating with the flow path and provided with a spring for pressing the sleeve to constantly bias the valve seat and the valve seat packing together. .