JP7036639B2 - A steam trap having a safety mechanism and a closing means used for the safety mechanism of the steam trap. - Google Patents

Description

The steam trap having the safety mechanism according to the present application and the closing means used for the safety mechanism of the steam trap relate to a technique for draining the drain and ensuring safety when the steam trap is clogged with drain.

Industrial plants may have a piping system that transfers steam generated by the boiler to the supply destination at high temperature and high pressure. If steam is liquefied in this pipe and drain (condensed water of steam) is generated, it will hinder the transfer of steam, so it is necessary to drain the drain out of the pipe as appropriate.

For this reason, steam traps are provided throughout the piping system. The float type steam trap has a hollow float inside, and this float floats as the drain that has flowed into the steam trap stays, and the drain is automatically drained by opening the drain outlet formed near the bottom. It is designed to be discharged to the outside of the pipe. After draining, the float descends and closes the drain outlet, so steam leakage does not occur.

By the way, foreign matter such as dust and scale may adhere and accumulate on the drain outlet of the steam trap. If the drain outlet is blocked by such a foreign substance, the drain cannot be drained properly even if the float floats due to the retention of the drain, and the drain becomes full in the valve chamber of the steam trap. Drain clogging occurs, such as the drain flowing back into the piping connected to the pipe. If the drain is clogged, there is a risk of causing a serious accident such as the steam blocked from transfer flowing back into the boiler, or the steam filling the pipe and causing a high pressure to destroy the pipe.

In order to eliminate such a clogged state of drain, there is a technique disclosed in Patent Document 1 described later. In this technique, an exhaust valve port is provided in the upper part of the valve chamber of the steam trap, and a bimetal that reversely deforms according to the temperature is placed close to the upper side of the exhaust valve port.

In the technique disclosed in Patent Document 1 having such a configuration, the air in the valve chamber is discharged from the exhaust valve port which is open mainly in the initial stage of steam transfer, and then the high temperature and high pressure steam is discharged from the valve. When it flows into the chamber, the bimetal protrudes and deforms in response to high temperature, closing the exhaust valve port and preventing steam leakage.

When a clogged drain occurs in the valve chamber of the steam trap, the bimetal is forcibly inverted and deformed by the pressure of the drain (fluid pressure), and the exhaust valve port is automatically opened to drain the drain from here. do.

Japanese Unexamined Patent Publication No. 10-2491

The technique disclosed in Patent Document 1 described above is intended to forcibly reverse and deform the bimetal by the pressure of the drain when a clogged state of the drain occurs, and to discharge the drain. However, the bimetal is originally peripheral. Since it is configured to deform in response to changes in temperature, it may not be possible to forcibly reverse and deform it with the pressure of the drain depending on the situation.

If the clogged state of the drain cannot be cleared, there is a danger of causing a serious accident such as the steam blocked from transfer flowing back to the boiler as described above, or the steam filling the pipe and causing a high pressure to destroy the pipe. It may lead to a serious situation.

Therefore, the steam trap having the safety mechanism and the closing means used for the safety mechanism of the steam trap according to the present application have a problem of solving these problems, and can surely eliminate the clogged state and secure the safety. It is an object of the present invention to provide a steam trap having a mechanism and a closing means used for a safety mechanism of the steam trap.

The steam trap having the safety mechanism according to the present application is
In a steam trap that discharges fluid from the first discharge section to the outside of the valve chamber when the stagnant fluid level of the fluid that has flowed into the valve chamber reaches a predetermined reference level.
Second discharge section, formed above the reference level,
It is a closed part that closes the second discharge part and prevents the outflow of the fluid from the second discharge part. Closure, which leads to the release of the outflow of
It is characterized by being equipped with.

Further, the closing means used for the safety mechanism of the steam trap according to the present application is
It is a closing means used for the safety mechanism of the steam trap that discharges the fluid from the first discharge part to the outside of the valve chamber when the accumulated fluid level of the fluid flowing into the valve chamber reaches a predetermined reference level.
A closed part that blocks the outflow of fluid from the second discharge part formed above the reference level, and the fluid from the second discharge part due to the progress of electrolytic corrosion due to the electrochemical action due to contact with the fluid. Closure, which leads to the release of the outflow of
It is characterized by being equipped with.

In the steam trap having the safety mechanism according to the present application and the closing means used for the safety mechanism of the steam trap, the closed portion undergoes electrolytic corrosion due to electrochemical action due to contact with the fluid, and the fluid flows out from the second discharge portion. To open up.

Therefore, when a clogged state occurs in which the fluid is not properly discharged from the first discharge part, the stagnant fluid surface exceeds the reference level and the fluid stays, and the contact between this fluid and the closed part opens the second discharge part. , The fluid is discharged out of the valve chamber through the second discharge section. Therefore, the clogged state in the steam trap is surely eliminated, and safety can be ensured.

It is sectional drawing of the steam trap 90 which shows 1st Embodiment of the steam trap which has the safety mechanism which concerns on this application, and the closing means used for the safety mechanism of a steam trap. FIG. 3 is an enlarged cross-sectional view of the vicinity of the escape bypass 2 and the closing bolt 4 shown in FIG. It is an enlarged sectional view around the escape bypass 2 and the occlusion bolt 40 in the steam trap which shows the 2nd Embodiment of the steam trap which has the safety mechanism which concerns on this application, and the closing means used for the safety mechanism of a steam trap. It is an enlarged sectional view around the escape bypass 2 and the occlusion bolt 50 in the steam trap which shows the 3rd Embodiment of the steam trap which has the safety mechanism which concerns on this application, and the closing means used for the safety mechanism of a steam trap.

[Explanation of terms in the embodiment]
The main terms shown in the embodiments correspond to the following elements of the steam trap having the safety mechanism according to the present application and the closing means used in the safety mechanism of the steam trap, respectively.
Bypass for escape 2 ・ ・ ・ Second discharge part Closure bolt 4, 40, 50, Electrolytic piece 6, Screw thread 40a, Locking protrusion 50a ・ ・ ・ Closing part, Closing means Opening level 85 ・ ・ ・ Reference level Drain discharge Outlet 97 ・ ・ ・ First discharge part Drain ・ ・ ・ Fluid Drain horizontal plane ・ ・ ・ Retained fluid surface

[First Embodiment]
A first embodiment of a steam trap having a safety mechanism according to the present application and a closing means used for the safety mechanism of the steam trap will be described.

(Explanation of steam trap)
Industrial plants may have a piping system that transfers steam generated by the boiler to the supply destination at high temperature and high pressure. When steam liquefies in this pipe, drain (condensed steam water) stays and hinders the transfer of steam.

In order to avoid such a situation, a large number of steam traps are provided everywhere in the piping. FIG. 1 is a cross-sectional view of the steam trap 90 in the present embodiment. A branch pipe 81 is provided in communication with the main pipe (not shown) of the pipe, and the connection port 99 provided in the steam trap main body 90h is connected to this branch pipe 81. Then, steam and drain flow in the direction of arrow 101 from the connection port 99 into the valve chamber 91 of the steam trap main body 90h. A cylindrical screen 80 is provided on the steam trap main body 90h, and steam and drain flow through the screen 80.

A drain outlet 97 is provided below the valve chamber 91 of the steam trap main body 90h, but normally, this drain outlet 97 is blocked by the float 95 to prevent steam leakage. ing. The float 95 is configured as a hollow sphere.

When the drain stays in the valve chamber 91 and the water level of the drain reaches the opening level 85, the float 95 rises to the arrow 105 and opens the drain discharge port 97. The drain accumulated by this is discharged from the drain discharge port 97 through the drain discharge path 98 in the direction of the arrow 102 to the drain recovery pipe 82 according to the momentum based on the high pressure in the pipe.

A partition plate 83 is provided in the valve chamber 91 to prevent the float 95 from being excessively lifted. The partition plate 83 is made of a mesh-like member so that steam and drain can pass through.

Further, in the present embodiment, the upper discharge port 96 is formed on the main body lid 92 attached to the steam trap main body 90h, and the X element 60 is provided in the vicinity of the upper discharge port 96. This X element 60 is mainly for discharging the air existing in the piping and the steam trap body 90h from the upper discharge port 96 in the initial stage of steam transfer to eliminate the air binding (air obstacle). ..

When the ambient temperature is low, the X element 60 contracts due to the action of the thermoliquid (temperature sensitive liquid) enclosed inside to open the upper discharge port 96, and air from the upper discharge port 96 through the upper discharge passage 88. Is discharged in the direction of arrow 103. The upper discharge passage 88 is formed in the main body lid 92 and is connected to the drain discharge passage 98. Subsequently, when steam flows into the valve chamber 91, the X element 60 expands due to the high temperature atmosphere of the steam and closes the upper discharge port 96. This prevents steam from leaking from the upper outlet 96.

(Explanation of safety mechanism)
In the steam trap 90 of the present embodiment, when the drain discharge port 97 is blocked by foreign matter such as dust or scale and a drain is clogged, such that the drain cannot be discharged properly, this clogged state is automatically set. A safety mechanism is provided to eliminate the problem. This safety mechanism will be described below.

As shown in FIG. 1, the main body lid 92 attached to the steam trap main body 90h is formed with an escape bypass 2 toward the upper discharge passage 88, and communicates the valve chamber 91 and the upper discharge passage 88. I'm letting you. In this embodiment, the escape bypass 2 is located above the open level 85 and above the partition plate 83 and the X element 60. In this embodiment, the upper part means a direction in which the water level rises due to the retention of drainage.
Then, the closing bolt 4 is screwed into the escape bypass 2. The closing bolt 4 normally closes the escape bypass 2 so that the steam flowing into the valve chamber 91 does not leak to the upper discharge passage 88 side.

FIG. 2 is an enlarged cross-sectional view of the vicinity of the escape bypass 2 and the closing bolt 4. In FIG. 2, the closing bolt 4 is also shown as a cross section. The closing bolt 4 is attached to the main body lid 92 by screwing the screw thread formed on the outer peripheral surface of the shaft portion of the closing bolt 4 into the screw groove formed on the inner peripheral surface of the escape bypass 2. .. A gasket 21 is interposed between the head portion of the closing bolt 4 and the mounting surface of the main body lid 92, and the gasket 21 prevents steam leakage from the escape bypass 2.

The closing bolt 4 is provided with a through hole 4S penetrating from the head portion to the tip portion along the central axis thereof. Then, the electrolytic corrosion piece 6 is fixed in the vicinity of the tip portion of the through hole 4S. Since the side circumference of the electrolytic corrosion piece 6 is fixed to the inner peripheral surface of the escape bypass 2 without a gap, steam leakage does not occur from here in normal times. In the present embodiment, the main body lid 92 and the closing bolt 4 are made of an iron material, and the electrolytic corrosion piece 6 is made of an aluminum material.

When the drain is clogged, even if the horizontal surface of the drain staying in the valve chamber 91 reaches the open level 85 and the float 95 floats, the drain is not discharged from the drain discharge port 97, and the horizontal surface of the drain is subsequently changed. Also rises, the valve chamber 91 becomes full, and the closing bolt 4 is reached. Further, the drain penetrates into the through hole 4S of the closing bolt 4 in the direction of arrow 107 and comes into contact with the electrolytic corrosion piece 6.

As a result, the electrolytic corrosion piece 6 is electrolytically corroded and the electrons are eluted into the drain. Here, electrolytic corrosion is a corrosion phenomenon due to electrochemical action, and when two different metals come into contact with an electrolyte solution at the same time, the metal having a strong ionization tendency (relatively low potential) is ionized due to the potential difference between the metals. This is a phenomenon in which electrons move to a metal with a low tendency (relatively high potential), and the atoms of the metal (metal with relatively low potential) that have lost their charge dissolve into the solution as ions, causing the metal to corrode.

As described above, in the present embodiment, the material of the main body lid 92 and the closing bolt 4 is iron, the material of the electrolytic corrosion piece 6 is aluminum, and the potential of aluminum is lower than the potential of iron. Therefore, the electrons of the low-potential aluminum electrolytic corrosion piece 6 are eluted in the drain as the electrolyte solution, and the electrolytic corrosion piece 6 gradually disappears with the passage of time.

After the drain comes into contact with the electrolytic corrosion piece 6, the time until the electrolytic corrosion piece 6 disappears and the escape bypass 2 is opened can be freely controlled by setting the electrolytic corrosion piece 6 to a specific thickness 6a. can do.

When the electrolytic corrosion piece 6 disappeared due to electrolytic corrosion, the escape bypass 2 was opened, and the drain that had accumulated in the valve chamber 91 followed the high-pressure momentum in the pipe and passed through the escape bypass 2 in the direction of arrow 108. It is discharged to the upper discharge channel 88. In this way, the clogged state of the drain is cleared.

In this embodiment, paying attention to the fact that the upper discharge passage 88 provided for eliminating the air binding by the operation of the X element 60 is formed above the valve chamber 91, the escape bypass 2 to the upper discharge passage 88 are formed. It adopts a configuration that drains the drain toward. Therefore, it is not necessary to separately provide a discharge path communicating with the escape bypass 2, and the configuration can be simplified.

By the way, since the escape bypass 2 is opened, steam leakage will occur from here thereafter. However, for industrial plants, the loss due to steam leakage is less than the risk loss associated with a clogged drain, so there is practically no problem. In addition, when such a steam leak occurs, the steam leak can be easily eliminated by replacing the main body lid 92 with the steam leak with a main body lid 92 equipped with a new closing bolt 4 with an electrolytic corrosion piece 6. It is possible to do.

In the present embodiment, in the through hole 4S of the closing bolt 4, the electrolytic corrosion piece 6 is provided near the tip portion of the closing bolt 4, but it can also be provided near the central portion or the head portion.

[Second Embodiment]
Next, a second embodiment of the steam trap having the safety mechanism according to the present application and the closing means used for the safety mechanism of the steam trap will be described. The basic configuration of the steam trap 90 according to the present embodiment is the same as the configuration shown in FIG. 1 in the first embodiment. In the present embodiment, the closing bolt 40 is provided instead of the closing bolt 4 in the first embodiment.

FIG. 3 is an enlarged cross-sectional view of the vicinity of the escape bypass 2 and the closing bolt 40 in the present embodiment. A screw thread 40a is provided on the shaft portion of the closing bolt 40 only once. A gasket 22 is fixedly attached to the tip of the closing bolt 40. The closing bolt 40 in the present embodiment is made of an aluminum material.

On the other hand, a screw groove is formed on the inner peripheral surface of the escape bypass 2 of the main body lid 92 as in the first embodiment. The closing bolt 40 is attached to the main body lid 92 by screwing the thread 40a of the closing bolt 40 into this screw groove.

Since the stopper 44 is fixed to the main body lid 92 on the outside of the escape bypass 2 of the main body lid 92, the gasket 22 is compressed by screwing the closing bolt 40, and the screw of the closing bolt 40 is screwed according to the elastic force. The ridge 40a is pressed against the thread groove, and the closing bolt 40 is firmly attached in the escape bypass 2. Further, due to the presence of the gasket 22, steam leakage does not occur from the escape bypass 2 in the normal state.

When the drain is clogged in the steam trap 90, the valve chamber 91 becomes full and the drain reaches the closing bolt 40. Then, the drain penetrates into the thread groove of the escape bypass 2 in the direction of arrow 107 from the gap of the head portion of the closing bolt 40. Here, since the material of the closing bolt 40 is aluminum as described above, the electrons of the screw thread 40a are eluted into the drain by electrolytic corrosion, and the screw thread 40a gradually disappears with the passage of time.

As a result, the gasket 22 fixed to the closing bolt 40 and the tip of the closing bolt 40 falls by its own weight while receiving the force of the elastic force of the gasket 22, and the escape bypass 2 is opened. The time from when the drain comes into contact with the closing bolt 40 until the thread 40a disappears and the escape bypass 2 is opened can be freely controlled by setting the thread 40a to a specific height. ..

Due to the opening of the escape bypass 2, the drain accumulated in the valve chamber 91 is discharged to the upper discharge passage 88 along the arrow 108 direction according to the momentum of the high pressure in the pipe. In this way, the clogged state of the drain is cleared.

Since the partition plate 83 is provided in the valve chamber 91 of the steam trap 90, the dropped closing bolt 40 and the gasket 22 stop on the partition plate 83, and the float 95 is caused by the falling of the closing bolt 40 and the gasket 22. There is no problem with the floating of the drain and the drainage from the drain discharge port 97 (see FIG. 1).

In the present embodiment, the closing bolt 40 is made of aluminum, but the closing bolt 40 may be made of iron and only the thread 40a may be made of aluminum.

[Third Embodiment]
Next, a third embodiment of the steam trap having the safety mechanism according to the present application and the closing means used for the safety mechanism of the steam trap will be described. The basic configuration of the steam trap 90 according to the present embodiment is the same as the configuration shown in FIG. 1 in the first embodiment, and the steam trap 90 is closed in the present embodiment instead of the closing bolt 4 in the first embodiment. Bolt 50 is provided.

FIG. 3 is an enlarged cross-sectional view of the vicinity of the escape bypass 2 and the closing bolt 50 in the present embodiment. In the present embodiment, what is formed on the inner peripheral surface of the escape bypass 2 is not a screw groove but an annular locking recess 2a. On the other hand, the shaft portion of the closing bolt 50 is provided with a locking projection 50a corresponding to the locking recess 2a. A gasket 22 is fixedly attached to the tip of the closing bolt 50. The closing bolt 50 in this embodiment is made of an aluminum material.

When this closing bolt 50 is attached to the main body lid 92, the closing bolt 50 is press-fitted in the direction of arrow 107 with respect to the escape bypass 2. Since the protrusion height of the locking protrusion 50a is formed to be relatively low, the locking protrusion 50a is fitted into the locking recess 2a by press fitting.

Similar to the second embodiment, a stopper 44 is fixed to the main body lid 92 on the outside of the escape bypass 2 of the main body lid 92, and the gasket 22 is compressed by press-fitting the closing bolt 50, and this elastic force is obtained. Therefore, the locking protrusion 50a of the closing bolt 50 is pressed against the locking recess 2a, and the closing bolt 50 is firmly attached in the escape bypass 2. Further, due to the presence of the gasket 22, steam leakage does not occur from the escape bypass 2 in the normal state.

When the drain is clogged in the steam trap 90, the valve chamber 91 becomes full and the drain reaches the closing bolt 50. Then, the drain penetrates into the locking recess 2a of the escape bypass 2 in the direction of arrow 107 from the gap of the head portion of the closing bolt 50. Here, since the material of the closing bolt 50 is aluminum as described above, the electrons of the locking projection 50a are eluted into the drain by electrolytic corrosion, and the locking projection 50a gradually disappears with the passage of time.

As a result, the gasket 22 fixed to the closing bolt 50 and the tip of the closing bolt 50 falls by its own weight while receiving the force of the elastic force of the gasket 22, and the escape bypass 2 is opened. The time from when the drain comes into contact with the closing bolt 50 until the locking projection 50a disappears and the escape bypass 2 is opened can be freely controlled by setting the locking projection 50a to a specific protrusion height. be able to.

Due to the opening of the escape bypass 2, the drain accumulated in the valve chamber 91 is discharged to the upper discharge passage 88 along the arrow 108 direction according to the momentum of the high pressure in the pipe. In this way, the clogged state of the drain is cleared.

Since the partition plate 83 is provided in the valve chamber 91 of the steam trap 90, the dropped closing bolt 50 and the gasket 22 stop on the partition plate 83, and the float 95 is caused by the falling of the closing bolt 50 and the gasket 22. There is no problem with the floating of the drain and the drainage from the drain discharge port 97 (see FIG. 1).

In the present embodiment, the closing bolt 50 is made of an aluminum material, but the closing bolt 50 may be made of an iron material and only the portion of the locking projection 50a may be made of aluminum.

[Other embodiments]
In each of the above-described embodiments, the electrolytic corrosion piece 6, the screw thread 40a, and the locking projection 50a, which are eliminated by electrolytic corrosion, are made of an aluminum material, and the main body lid 92 and the like are made of an iron material to cause electrolytic corrosion. However, several other metal materials having a potential difference may be adopted and used for a portion where the material having a relatively low potential disappears. In this case, the larger the potential difference between several types of metal materials, the stronger the tendency for corrosion due to electrolytic corrosion to be promoted. Therefore, it is efficient to select a metal material having a large potential difference.

Further, the configuration shown in each of the above embodiments is an example, as long as the configuration is such that the outflow of the fluid from the discharge portion is released by the progress of electrochemical action due to the electrochemical action due to the contact with the fluid such as drain. Other configurations can be adopted.

2: Escape bypass 4, 40, 50: Closure bolt 6: Electrolytic piece 40a: Thread
50a: Locking protrusion 85: Open level 97: Drain outlet

Claims (2)

In a steam trap that discharges fluid from the first discharge section to the outside of the valve chamber when the stagnant fluid level of the fluid that has flowed into the valve chamber reaches a predetermined reference level.
Second discharge section, formed above the reference level,
It is a closed part that closes the second discharge part and prevents the outflow of the fluid from the second discharge part. Closure, which leads to the release of the outflow of
A steam trap with a safety mechanism characterized by being equipped with. It is a closing means used for the safety mechanism of the steam trap that discharges the fluid from the first discharge part to the outside of the valve chamber when the accumulated fluid level of the fluid flowing into the valve chamber reaches a predetermined reference level.
A closed part that blocks the outflow of fluid from the second discharge part formed above the reference level, and the fluid from the second discharge part due to the progress of electrolytic corrosion due to the electrochemical action due to contact with the fluid. Closure, which leads to the release of the outflow of
A closing means used for the safety mechanism of the steam trap, which is characterized by being equipped with.

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