WO2016013427A1

WO2016013427A1 - Steam trap

Info

Publication number: WO2016013427A1
Application number: PCT/JP2015/069902
Authority: WO
Inventors: 小池正
Original assignee: 株式会社テイエルブイ
Priority date: 2014-07-23
Filing date: 2015-07-10
Publication date: 2016-01-28
Also published as: JPWO2016013427A1; JP6022733B2

Abstract

The purpose of the present invention is to provide a steam trap equipped with a cleaning mechanism capable of shortening the time necessary for drainage discharge actions when starting operation. The steam trap (1) is equipped with: a casing (10) with a small diameter section (16a), which is a drainage discharge port; a bimetal (22), which is provided at a position through which the drainage discharged from the small diameter section (16a) flows and which is displaced due to temperature changes; and a rod-shaped cleaning member (30) for removing foreign matter in the small diameter section (16a) by advancing and retracting from the outside of the small diameter section (16a) as a result of displacement of the bimetal (22). The proportion of the cross-sectional area (A1) of the portion of the cleaning member (30) that enters into the small diameter section (16a) with respect to the area (A2) of the opening of the small diameter section (16a) is 0.3 to 0.8.

Description

steam trap

This application relates to a steam trap that discharges drain generated in a steam piping system or the like.

For example, as disclosed in Patent Document 1, a steam trap having a cleaning mechanism for removing foreign matter clogged in a drain (condensate) discharge port is known. This cleaning mechanism includes a displacement member (temperature responsive member) that is displaced by a change in temperature, and a rod-like operation member that moves forward and backward to the discharge port by the displacement of the displacement member. The displacement member is provided in a discharge passage through which the drain discharged from the discharge port flows. In this cleaning mechanism, when the drain is discharged, the displacement member is heated by the drain and the operation member is retracted. On the other hand, when the foreign matter is clogged in the discharge port and the drain is not discharged, the displacement member is displaced due to a temperature drop, and the operation member advances by the displacement and enters the discharge port. By the entry of the operation member, the foreign matter clogged in the discharge port is removed. Thus, the cleaning mechanism can automatically clean the discharge port without human operation.

JP 2007-138984 A

By the way, at the start of the operation of the steam piping system, it is necessary to discharge the drain accumulated in the piping (low temperature drain) from the steam trap. However, the steam trap as described above has a problem that it takes time for the draining operation to be performed at the start of operation. That is, in the steam trap when the operation is stopped, since there is no circulation of the drain, the displacement member of the cleaning mechanism is displaced due to the temperature drop, and the operation member enters the discharge port. Therefore, in the steam trap at the start of operation, the discharge port is almost closed by the operation member, and the drain cannot be discharged quickly.

The technology disclosed in the present application has been made in view of such circumstances, and an object thereof is to provide a steam trap having a cleaning mechanism that can shorten the time required for drain discharge operation at the start of operation.

The technology disclosed in the present application includes a casing having a drain discharge port, a displacement member provided at a position where the drain discharged from the discharge port circulates, and a displacement member that is displaced by a temperature change. It is premised on a steam trap provided with a rod-shaped cleaning member that moves forward and backward from the outside of the navel to remove foreign matter from the discharge port. And the ratio of the cross-sectional area of the part which approachs the said discharge port of the said cleaning member with respect to the opening area of the said discharge port is 0.3 or more and 0.8 or less.

As described above, according to the steam trap of the present application, since the ratio of the cross-sectional area of the portion that enters the discharge port of the cleaning member to the opening area of the discharge port is set to 0.8 or less, the cleaning member enters the discharge port. When it does, the clearance gap which can fully discharge | drain drain can be formed between a discharge port and the cleaning member. Therefore, it is possible to quickly drain the drain in the steam trap at the start of operation, and thus it is possible to reduce the time required for draining operation.

Moreover, since the ratio of the cross-sectional area of the portion entering the discharge port of the cleaning member with respect to the opening area of the discharge port is set to 0.3 or more, the foreign substance removing function by the cleaning member can be ensured. That is, according to the steam trap of the present application, when the cleaning member enters the discharge port clogged with foreign matter, first, the foreign matter in the central region through which the cleaning member passes is pushed out and removed. Then, the drain is discharged from the opening formed by removing the foreign matter. Since the flow of the drain discharged from the opening is high speed, the remaining foreign matter is removed by the high speed flow of the drain. In this way, foreign substances clogged in the discharge port can be removed. The range in which such effects can be obtained (that is, the foreign matter removing function by the cleaning member can be ensured) is the lower limit value of the ratio of the cross-sectional area of the cleaning member to the opening area of the discharge port. As described above, according to the steam trap of the present application, it is possible to reduce the time required for the drain discharge operation at the start of operation while ensuring the foreign matter removing function by the cleaning member.

FIG. 1 is a cross-sectional view illustrating a schematic configuration of a steam trap according to an embodiment. FIG. 2 is an enlarged sectional view showing a schematic configuration of the cleaning mechanism. FIG. 3 is an enlarged cross-sectional view illustrating a schematic configuration of the cleaning mechanism. FIG. 4 is an enlarged cross-sectional view illustrating a schematic configuration of the cleaning mechanism.

Hereinafter, embodiments of the present application will be described with reference to the drawings. Note that the following embodiments are essentially preferable examples, and are not intended to limit the scope of the technology disclosed in the present application, applications thereof, or uses thereof.

The steam trap 1 of the present embodiment constitutes a float type steam trap, and is provided in, for example, a steam system, and automatically discharges drain (condensate) generated by condensation of steam. As shown in FIG. 1, the steam trap 1 includes a casing 10 that is a sealed container, and a cleaning mechanism 20.

The casing 10 has a lid portion 12 fastened to a main body portion 11 with bolts, and a valve chamber 13 is formed inside. The main body 11 has a drain inflow passage 14. The casing 10 also has a discharge passage 17 formed across the main body 11 and the lid 12. The inflow passage 14 communicates with the upper portion of the valve chamber 13. A valve seat 15 that is screwed to the lid portion 12 is provided at the lower portion of the valve chamber 13. A discharge passage 16 that communicates with the discharge passage 17 is formed in the valve seat 15. The discharge passage 16 is a straight passage, and includes a small diameter portion 16a, a tapered portion 16b, a medium diameter portion 16c, and a large diameter portion 16d that are sequentially formed from the valve chamber 13 side. Here, the small-diameter portion 16a of the discharge passage 16 is a drain discharge port according to the claims of the present application, and constitutes a so-called orifice.

The valve chamber 13 is provided with a hollow spherical float 18 in a free state. The float 18 opens and closes the discharge passage 16 of the valve seat 15 by being separated from and seated on the valve chamber side end surface of the valve seat 15. The lid 12 is provided with a float seat 19 with which the float 18 comes into contact with the discharge passage 16 being closed. Note that two float seats 19 are provided on the front side and the other side in FIG. In the steam trap 1, the drain that flows into the valve chamber 13 from the inflow passage 14 is discharged from the discharge passage 16 (small diameter portion 16 a) of the valve seat 15 and flows out through the discharge passage 17.

The cleaning mechanism 20 automatically removes foreign matter adhering to the small diameter portion 16a of the discharge passage 16, and is provided on the lid portion 12 as shown in FIG. That is, the cleaning mechanism 20 is located outside the valve chamber 13. The cleaning mechanism 20 includes a case 21, a bimetal 22, and a cleaning member 30.

The case 21 is formed in a substantially cylindrical shape, and is screwed on the same axis as the valve seat 15 in the lid portion 12. A bimetal 22 is accommodated in the case 21. The bimetal 22 has a plate shape in which two kinds of metals or alloys having different thermal expansion coefficients are firmly bonded, and constitutes a displacement member according to the claims of the present application. That is, the bimetal 22 is a temperature responsive member that bends (displaces) in response to a temperature change. The bimetal 22 of the present embodiment is formed in a double spiral shape by further spirally winding a strip-shaped bimetal flat plate. The bimetal 22 has a small radius and a long length when the temperature is low, and a large radius and a short length when the temperature is high. That is, the bimetal 22 expands and contracts in the axial direction due to temperature changes.

The cleaning mechanism 20 is configured such that drain discharged from the discharge passage 16 of the valve seat 15 flows into the case 21. That is, the bimetal 22 is provided at a position where the drain discharged from the small diameter portion 16a of the discharge passage 16 flows and is exposed to the discharged drain.

The cleaning member 30 is formed in a rod shape with a circular cross section and is accommodated in the case 21. The cleaning member 30 is provided so as to be coaxial with the case 21. The cleaning member 30 includes a base portion 31 and an operation portion 32 that are continuously formed in the axial direction. The operation portion 32 is located on the valve seat 15 side and is formed with a smaller diameter than the base portion 31. The cleaning member 30 has a base 31 inserted into the bimetal 22. An adjustment member 23 is screwed to one end of the case 21. One end of the bimetal 22 is fixed to the adjustment member 23, and the other end is fixed to a receiving portion 31 a formed on the base portion 31 of the cleaning member 30. The receiving portion 31 a is an annular plate provided in the circumferential direction of the base portion 31, and supports the other end of the bimetal 22 at its end surface.

The cleaning member 30 is configured to advance and retract from the outside to the small-diameter portion 16a of the discharge passage 16 by the displacement of the bimetal 22 to remove foreign matters in the small-diameter portion 16a. That is, the cleaning member 30 moves in the axial direction by the expansion and contraction operation due to the temperature change of the bimetal 22. Specifically, when the bimetal 22 extends due to a temperature drop, the receiving portion 31a is pushed by the bimetal 22 and the cleaning member 30 moves forward (moves toward the small diameter portion 16a side of the discharge passage 16). On the contrary, when the bimetal 22 is shortened due to the temperature rise, the receiving portion 31a is pulled by the bimetal 22, and the cleaning member 30 moves backward (moves away from the small diameter portion 16a of the discharge passage 16). The end portion of the base portion 31 of the cleaning member 30 is slidably inserted into a guide hole 24 formed in the adjustment member 23.

As shown in FIGS. 2 to 4, the operation portion 32 of the cleaning member 30 is formed with a small diameter portion 34 (tip portion) and a large diameter portion 33 in order from the small diameter portion 16a side of the discharge passage 16. The small diameter portion 34 has a diameter (thickness) smaller than that of the large diameter portion 33 and is a portion that enters the small diameter portion 16 a of the discharge passage 16. On the front end side of the large diameter portion 33. A tapered portion 37 is formed which becomes gradually thinner as it goes to the small diameter portion 34.

And the cross-sectional area A1 (hereinafter referred to as the cross-sectional area A1 of the cleaning member 30) of the small-diameter portion 34 of the operation portion 32 and the opening area A2 of the small-diameter portion 16a of the discharge passage 16 (hereinafter referred to as the opening area A2 of the discharge passage 16). And a certain relationship. Specifically, as shown in FIG. 4, the ratio (A1 / A2) of the cross-sectional area A1 of the cleaning member 30 to the opening area A2 of the discharge passage 16 is set to 0.3 or more and 0.8 or less.

In the steam trap 1 of the present embodiment, when operating (when the steam system is operating), high-temperature drain flows in and is discharged. That is, high-temperature drain flows in the steam trap 1. In this case, in the cleaning mechanism 20, the bimetal 22 is exposed to high-temperature drain, and the temperature rises to 90 ° C. or more, for example. Therefore, as shown in FIG. 2, the bimetal 22 is shortened, and thereby the cleaning member 30 is retracted. Therefore, the small diameter portion 16a of the discharge passage 16 is fully opened.

Further, in the steam trap 1 of the present embodiment, when foreign matter is clogged in the small diameter portion 16 a of the discharge passage 16, no or almost no drainage is discharged from the discharge passage 16. For this reason, the bimetal 22 is not exposed to the high-temperature drain and the temperature is lowered. Then, the bimetal 22 expands, and the cleaning member 30 moves forward as shown in FIG. 3 or FIG. 4 so that the operation part 32 enters the small diameter part 16 a of the discharge passage 16. FIG. 3 shows a case where the temperature of the bimetal 22 is slightly lowered (for example, to 80 ° C.), and the tip of the operation part 32 of the cleaning member 30 and the outer end face of the small diameter part 16a of the discharge passage 16 are flush with each other. It becomes a state. FIG. 4 shows a case where the temperature of the bimetal 22 is further lowered (for example, to 70 ° C. or less), and the tip of the operation portion 32 of the cleaning member 30 protrudes from the small diameter portion 16 a of the discharge passage 16.

Here, since the ratio of the cross sectional area A1 of the cleaning member 30 to the opening area A2 of the discharge passage 16 is set to 0.3 or more, the cleaning member 30 enters the small diameter portion 16a of the discharge passage 16 as described above. As a result, the foreign matter clogged in the small diameter portion 16a can be removed. That is, when the cleaning member 30 enters the small-diameter portion 16a clogged with foreign matter, first, the foreign matter in the central region through which the cleaning member 30 (small-diameter portion 34 of the operation unit 32) passes is pushed out and removed. Is done. Then, the drain is discharged from the opening formed by removing the foreign matter. Since the flow of the drain discharged from the opening is high speed, the remaining foreign matter is removed by the high speed flow of the drain. In this way, foreign substances clogged in the small diameter portion 16a of the discharge passage 16 can be removed.

Also, at the start of operation of the steam system, it is necessary to discharge low temperature drain accumulated in the pipe from the steam trap 1. In the steam trap 1 when the operation is stopped, since there is no circulation of the drain, the bimetal 22 expands due to a decrease in temperature, whereby the cleaning member 30 moves forward as shown in FIGS. 3 and 4 and the small diameter portion 16 a of the discharge passage 16. It enters the state that entered.

Here, in the steam trap 1 of this embodiment, since the ratio of the cross-sectional area A1 of the cleaning member 30 to the opening area A2 of the discharge passage 16 is set to 0.8 or less, the cleaning member 30 has a small diameter of the discharge passage 16. Even in a state of entering the portion 16a, a gap that can sufficiently discharge the low-temperature drain can be formed between the small diameter portion 16a and the cleaning member 30. Therefore, the low temperature drain can be quickly discharged from the steam trap 1 at the start of operation. Therefore, the time taken for the low temperature drain discharge operation can be shortened.

As described above, according to the steam trap 1 of the present embodiment, the ratio (A1 / A2) of the transverse area A1 of the cleaning member 30 to the opening area A2 of the discharge passage 16 is set within a predetermined range. It is possible to reduce the time required for the drain discharge operation at the start of operation while securing the foreign matter removing function by the above.

The technique disclosed in the present application is useful for a steam trap having a cleaning mechanism for removing foreign matter adhering to a drain outlet.

1 Steam trap 10 Casing 16a Small diameter part (discharge port)
22 Bimetal (displacement member)
30 Cleaning member

Claims

A casing having a drain discharge port, a displacement member provided at a position where the drain discharged from the discharge port circulates, and a displacement member that is displaced by a temperature change, and the displacement member is moved forward and backward from the outside by the displacement of the displacement member. A steam trap provided with a rod-shaped cleaning member for removing foreign matter from the discharge port,
The ratio of the cross-sectional area of the portion of the cleaning member that enters the discharge port to the opening area of the discharge port is 0.3 to 0.8.