JPH0926088A - Thermally-actuated steam trap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform intermittent opening and closing operations and also prevent water hammering from occurring. SOLUTION: A valve seat member 7 in which a lead path for interconnecting a valve chamber 3 with an outlet 5 is formed is installed between the valve chamber and the outlet. Also expanding media 23 and 25 are sealed in an internal space formed between right and left two diaphragms 14 and 15 of which responsibilities to a pressure variation are different from those of a wall member 13, and a temperature control element 9 in which a valve member 17 is attached to the diaphragms 14 and 15 is installed in the valve chamber 3 with the valve member 17 faced toward the valve seat member 7. Also through holes 10 and 16 are formed in the valve member 17 and valve seat member 7, and both through holes 10 and 16 are interconnected by a telescopable path member 18. Then a seal member 34 to seal between the inner wall 32 of a valve casing 2 and the outer surface of the temperature control element is provided. In addition, a seal surface 36 to close the lead path to the valve seat member 7 is formed on the valve member 17 at the seating of the valve member 17 onto the valve seat member 7, and also a seal surface 37 to close the through holes 10 and 16 in the valve member 17 is formed on the valve seat member 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam trap for automatically discharging condensate generated in various steam-using equipment and steam pipes, and more particularly, to a steam trap which is heated and cooled by steam and condensate and expanded according to the temperature. The present invention relates to a thermo-responsive steam trap for discharging condensate below a desired temperature out of the system by using a temperature control element containing a contracting medium.

[0002]

2. Description of the Related Art The basic structure of a heat-actuated steam trap is known from, for example, Japanese Unexamined Patent Publication No. 6-129598. As understood from the publication, a valve casing having an inlet, a valve chamber and an outlet is formed, a valve seat member having a lead-out passage communicating with the valve chamber and the outlet, and a valve member formed between a wall member and a diaphragm. It is equipped with a temperature control element in which an expansion medium is enclosed in the internal space and a valve member is attached to the diaphragm, the valve seat member is attached between the valve chamber and the outlet, and the valve member faces the valve seat member. Is installed in the valve chamber, a gap for fluid passage is provided between the inner peripheral wall of the valve casing and the outer periphery of the temperature control element, and the lead-out path of the valve seat member is closed when the valve member is seated on the valve seat member. The seal surface is formed on the valve member.

When the temperature in the valve chamber rises, the expansion medium expands, and the valve member is seated on the valve seat member via the diaphragm to close the outlet passage. This prevents steam from leaking out. When the temperature in the valve chamber decreases, the expansion medium contracts, and the valve member separates from the valve seat member to open the outlet passage. This discharges the condensate out of the system.

[0004]

In the heat-actuated steam trap of the above-mentioned type, since the opening / closing valve operation is repeated in small increments at the expansion / contraction temperature of the expansion medium,
There is a problem that the condensed water may be exhausted and misunderstood as a steam leak, and that the valve member and the valve seat member may be prematurely worn to cause a steam leak. Therefore, a technical problem of the present invention is to provide a heat-actuated steam trap which performs intermittent on-off valve operation.

However, if the operation of the on-off valve is intermittent, there is a risk that a rapid flow of fluid will occur at the inlet side or the outlet side, causing water hammer. Therefore, in addition to the above-mentioned technical problems, a technical problem of the present invention is to provide a heat-actuated steam trap which does not cause water hammer.

[0006]

[Means for Solving the Problems] The technical means of the present invention taken to solve the above-mentioned technical problems includes a valve casing having an inlet, a valve chamber and an outlet, and a valve chamber and an outlet communicating with each other. A valve seat member having a discharge passage formed therein and a temperature control element in which an expansion medium is enclosed in an internal space formed between the wall member and the diaphragm and the valve member is attached to the diaphragm. In the case where the temperature control element is installed in the valve chamber by mounting the valve member facing the valve seat member, the expansion member is enclosed between the wall member and the left and right diaphragms that have different responsiveness to pressure changes. Between the inner wall of the valve casing and the outer periphery of the temperature control element, two internal spaces are formed, and a through hole is formed in the wall member and the valve member, and both through holes are connected by a stretchable passage member. A seal member to seal the valve member A heat-actuated steel sheet having a valve seat having a seal surface for closing the lead-out path of the valve seat member when seated on the valve seat member and a seal surface for closing the through hole of the valve member. -In Mutrap.

The two diaphragms can be made to have different responsiveness to pressure changes by using diaphragms having different thicknesses. Further, the responsiveness to the pressure change can be made different by forming ripples on one side or by making the shapes of ripples formed on both sides different. Also, by using a diaphragm formed of materials having different elastic forces, it is possible to make the response to the pressure change different.

[0008]

The operation of the above technical means is as follows.
When the expansion medium expands due to the rise in the temperature in the valve chamber, first the diaphragm sensitive to one pressure change is displaced in the valve closing direction, and the seal surface of the valve member is displaced from the seal surface of the valve seat member. The valve member is partially seated on the valve seat member in an inclined posture. Subsequently, the diaphragm, which is insensitive to the other pressure change, is displaced in the valve closing direction and the seal surface of the valve member is placed parallel to the seal surface of the valve seat member so that the valve member is completely seated on the valve seat member. Sit down. As a result, the seal surface of the valve member closes the lead-out path of the valve seat member, and the seal surface of the valve seat member closes the through hole of the valve member.

The inner peripheral wall of the valve casing and the outer periphery of the temperature control element are sealed by a seal member, and the lead-out path and the through hole are closed, so that the temperature control device in the valve chamber is closed. It is divided into an inlet side and an outlet side with the element in between. The pressure in the outlet side valve chamber, which is isolated from the inlet side and becomes a closed space, also decreases as the temperature decreases. Therefore, the force for displacing the diaphragm facing the outlet side valve chamber in the valve opening direction decreases. This makes it difficult for the diaphragm to quickly displace when the expansion medium contracts due to the decrease in the temperature inside the valve chamber, and after the temperature inside the valve chamber further decreases, first the diaphragm sensitive to one pressure change is opened in the valve opening direction. Displacement, valve member seal
The valve member is partially separated from the valve seat member with the seat surface tilted with respect to the seal surface of the valve seat member. Subsequently, the diaphragm, which is insensitive to the other pressure change, is displaced in the valve opening direction, and the seal surface of the valve member is placed parallel to the seal surface of the valve seat member so that the valve member is completely removed from the valve seat member. Move away. As a result, the seal surface of the valve member fully opens the lead-out passage of the valve seat member, and the seal surface of the valve seat member fully opens the through hole of the valve member.

In this way, the diaphragm is displaced after the temperature in the valve chamber is sufficiently lowered, the valve member is separated from the valve seat member, and the seal surface of the valve member opens the lead-out path of the valve seat member. At the same time, the seal surface of the valve seat member opens the through hole of the valve member, so that the intermittent opening / closing valve operation can be performed. Further, the valve member is partially seated on the valve seat member and then fully seated to close the lead-out path and the through hole, and the valve member is partially separated from the valve seat member and then completely separated to the lead-out path and the through hole. By opening the hole, the sudden on-off valve operation is not performed and the risk of water hammer is eliminated.

[0011]

An embodiment showing a specific example of the above technical means will be described (see FIG. 1). In FIG. 1, the upper casing 1 and the lower casing 2 are screwed together to form a valve casing having a valve chamber 3 therein. The upper casing 1 has a valve chamber 3
An inlet 4 communicating with the lower casing 2 is formed in the lower casing 2.
Forming an outlet 5 communicating with A valve seat member 7 is screwed to a partition wall 6 between the valve chamber 3 and the outlet 5. The valve seat member 7 has a plurality of outlet passages 8 that connect the valve chamber 3 and the outlet 5.

A temperature control element 9 is arranged above the valve seat member 7. The temperature control element 9 includes a through hole 10, an injection port 11,
A wall member 13 forming 12; two diaphragms 14 and 15 on the left and right; a valve member 17 forming a through hole 16; and a passage member 18 connecting the through hole 10 of the wall member 13 and the through hole 16 of the valve member 17. A fixed wall member 20 having an opening through which the valve member 17 comes in and out, the wall member 13 and the right diaphragm 1
Expansion medium 23 injected into the internal space formed between
And the expansion medium 25 injected into the internal space formed between the wall member 13 and the left diaphragm 15.

Each of the diaphragms 14 and 15 has a substantially semicircular shape with its outer peripheral edge bent upward, and the right diaphragm 14 is formed thinner than the left diaphragm 15.
Ripples are formed on the diaphragms 14 and 15, respectively. The outer peripheral edges of the diaphragms 14 and 15 are wall members 1 respectively.
It is fixed to 3 by welding (locations 21 and 22).

The expansion medium 23 is injected into the internal space formed by the wall member 13 and the right diaphragm 14 from the injection port 11 of the wall member 13, and the injection port 11 is sealed by closing it with a plug member 24. Similarly, the expansion medium 25 is injected from the injection port 12 of the wall member 13 into the internal space formed by the wall member 13 and the left diaphragm 15.
Is closed by closing the plug member 26. The expansion mediums 23 and 25 are formed of water, a liquid having a boiling point lower than that of water, or a mixture thereof.

The valve member 17 is fixed to the diaphragms 14 and 15 by welding (reference numerals 27 and 28). Wall member 1
The one end side of the passage member 18 formed so as to be capable of expanding and contracting in the axial direction is welded (reference numeral 29) to the edge of the through hole 10 of No. 3, and the valve member 1
The other end side of the passage member 18 is welded (reference numeral 30) to the edge of the through hole 16 of FIG.
Linked by The outer peripheral edges of the wall member 13 and the fixed wall member 20 are welded (reference numeral 31).

In the temperature control element 9, the valve member 17 is arranged in the valve chamber 3 so as to face the valve seat member 7, and the sealing means is provided on the step portion 33 formed on the inner peripheral wall 32 of the lower casing 2. It is mounted via the gasket 34 as the above and is held by the snap ring 35. Inner peripheral wall 3 of lower casing 2 by gasket 34
2 and the outer periphery of the temperature control element 9 are sealed. Valve member 1
A seal surface 36 for closing the lead-out passage 8 of the valve seat member 7 when seated on the valve seat member 7 is formed on the lower surface of 7. Also, the valve seat member 7
Seal surface 3 for closing the through hole 16 of the valve member 17 on the upper surface of the
7 is formed.

When the temperature in the valve chamber 3 rises, the expansion medium 2
3, 25 expands, and the right diaphragm 14, which is thinly formed and is sensitive to the pressure change, is displaced downward, so that the valve member 17
The valve member 17 is partially seated on the valve seat member 7 with the seal surface 36 of the valve seat member 7 being inclined with respect to the seal surface 37 of the valve seat member 7. Then, the left diaphragm 15, which is insensitive to the pressure change formed thickly, is displaced downward, and the seat member of the valve member 17 is displaced.
The valve member 17 is fully seated on the valve seat member 7 with the seat surface 36 parallel to the seal surface 37 of the valve seat member 7. As a result, the seal surface 36 of the valve member 17 is connected to the outlet passage 8 of the valve seat member 7.
And the seal surface 37 of the valve seat member 7 is closed.
The through hole 16 of 7 is closed to prevent steam from leaking.

When the lead-out path 8 and the through hole 16 are closed,
Since the gasket 34 seals between the inner peripheral wall 32 of the lower casing 2 and the outer periphery of the temperature control element 9, the inside of the valve chamber 3 sandwiches the temperature control element 9 and the inlet 4 side and the outlet 5 side. Separated by. When the temperature inside the valve chamber 3 decreases, the expansion media 23 and 25 contract and the diaphragms 14 and 15 are displaced upward, but the outlet 5 of the valve chamber 3 decreases as the temperature decreases.
Since the pressure on the side also decreases and the force for displacing the diaphragms 14 and 15 upwards decreases, the right diaphragm 14 first displaces upward after the temperature inside the valve chamber 3 further decreases, and the seal of the valve member 17 decreases. The surface 36 is inclined with respect to the seal surface 37 of the valve seat member 7, and the valve member 17 is partially separated from the valve seat member 7. Then, the left diaphragm 15 is displaced upward so that the seal surface 36 of the valve member 17 is in a posture parallel to the seal surface 37 of the valve seat member 7 and the valve member 17 is moved to the valve seat member 7.
Completely separate from. As a result, the valve member 17
The seal surface 36 opens the outlet passage 8 of the valve seat member 7, and the seal surface 37 of the valve seat member 7 opens the through hole 16 of the valve member 17, and the condensate is discharged from the outlet 5.

In the above embodiment, the diaphragms having different thicknesses are exemplified, but the response to the pressure change can be obtained by forming the ripples on one diaphragm or by making the shapes of the ripples formed on both sides different. You can make them different. Further, by using diaphragms formed of materials having different elastic forces, for example, one diaphragm is made of stainless steel or nickel-molybdenum alloy represented by Hastelloy (trademark), and the other diaphragm is made of phosphor bronze. Alternatively, the responsiveness to pressure change may be made different by changing the carbon content or using different chemical components even if the same stainless steel is used.

[0020]

The present invention has the following specific effects. As described above, the heat-actuated steam trap according to the present invention is
Since intermittent on-off valve operation can be performed, there is no mistake for steam leakage at the time of condensate discharge, and wear of the valve member and valve seat member is less likely to occur. It can be carried out. Further, since the heat-actuated steam trap according to the present invention does not perform sudden opening / closing valve operation, it does not cause water hammer.

[Brief description of drawings]

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

[Explanation of symbols]

 1 Upper casing 2 Lower casing 3 Valve chamber 4 Inlet 5 Outlet 7 Valve seat member 8 Outlet passage 9 Temperature control element 10 Through hole 13 Wall member 14 Right diaphragm 15 Left diaphragm 16 Through hole 17 Valve member 18 Passage member 23 expansion medium 25 expansion medium 32 inner wall of valve casing 34 gasket 36 seal surface of valve member 37 seal surface of valve seat member

Claims (1)

[Claims] 1. A valve casing having an inlet, a valve chamber and an outlet formed therein, a valve seat member having a lead-out passage communicating with the valve chamber and the outlet, and an internal space formed between a wall member and a diaphragm. It is equipped with a temperature control element in which a medium is enclosed and a valve member is attached to the diaphragm.The valve seat member is attached between the valve chamber and the outlet, and the valve member faces the valve seat member so that the temperature control element is in the valve chamber. When installed, the two left and right diaphragms, which have different responsiveness to pressure changes from the wall member, form two left and right inner spaces for enclosing the expansion medium, and a through hole is formed in the wall member and the valve member, and the passage is expandable and contractible. A seal member that connects both through holes with a member and seals between the inner peripheral wall of the valve casing and the outer periphery of the temperature control element is provided, and when the valve member is seated on the valve seat member, Form a seal surface on the valve member that closes the outlet path At the same time, the heat-acting steam trap is characterized in that a seal surface for closing the through hole of the valve member is formed on the valve seat member.