WO2019107317A1

WO2019107317A1 - Nozzle-type steam trap

Info

Publication number: WO2019107317A1
Application number: PCT/JP2018/043450
Authority: WO
Inventors: 竜太郎芦田
Original assignee: 株式会社Ｓｈｉｎｓｅｉ
Priority date: 2017-11-30
Filing date: 2018-11-26
Publication date: 2019-06-06
Also published as: JP2019100418A; JP6323701B1

Abstract

The present invention relates to a nozzle-type steam trap and addresses the problem of guiding drainage preferentially to an inlet that leads to a nozzle, and reducing steam leakage. A steam trap (1) comprises: a housing (2); a nozzle (7) disposed in the housing; a first chamber (5a, 5h) which is disposed inside the housing and to which a suction port of the nozzle faces; a second chamber (6a) which is disposed inside the housing and to which an injection port of the nozzle faces; and a drainage introduction member (8) which is disposed in a steam introduction port (3) of the first chamber and in which a cutout section (8a) is formed. The drain introduction member (8) is attached so that the cutout section (8a) is located in a lower section where drainage from the steam introduction port (3) accumulates.

Description

Nozzle type steam trap

The present invention relates to a nozzle type steam trap.

BACKGROUND ART Conventionally, a steam trap is known as an apparatus for discharging a drain accumulated in steam piping in a plant facility or the like, that is, an apparatus in which vapor phase steam is liquefied. There are various types of steam traps according to the draining principle of drain, and one of them is, for example, a nozzle type steam trap as described in Patent Document 1 is known. As shown in FIG. 11, the steam trap 20 has an introduction portion 21 into which steam is introduced from the outside, a drainage portion 22 that discharges water to the outside, and an exhaust portion 23. A trap chamber 24 is provided inside. The injection port of the nozzle 25 faces the trap chamber 24 and captures water mixed in the steam introduced from the introduction unit 21 as condensed water. The top opening of the trap chamber 24 is shielded by the end cap 26. In addition, the exhaust unit 23 discharges the residual steam whose water has been removed by the trap chamber 24 to the outside, and a strainer 27 is provided therein.

JP 2014-234868 A

In the steam trap 20 of Patent Document 1, a drain having a specific gravity larger than that of the steam in the introduction portion 21 fills the exhaust portion 23 and the introduction portion 21 and then reaches the inlet to the nozzle 25. Since some steam first reaches the inlet to the nozzle 25 and is exhausted, a steam leak occurs. In particular, there is a problem that steam leakage is likely to occur at an installation point where the amount of drain is small.

Further, in the steam trap 20 of Patent Document 1, a metal gasket is used as a sealing material for the trap chamber 24 in which the nozzle 25 is installed and the exhaust portion 23 in which the strainer 27 is installed. However, there is a risk that high-pressure steam may be leaked due to thermal expansion, so it was necessary to periodically perform maintenance and inspection and replace the sealing material.

Therefore, an object of the present invention is to preferentially guide the drain to the inlet to the nozzle to reduce steam leakage. Another object of the present invention is to eliminate the burden of periodic inspection and replacement work of the sealing material.

In order to solve such problems, the present invention relates to a nozzle type steam trap,
And
A nozzle provided in the housing;
A first chamber provided in the housing and facing the suction port of the nozzle;
A second chamber provided in the housing and facing the injection port of the nozzle;
And a drain introducing member provided at the steam introducing port of the first chamber and having a notch formed therein,
The drain introducing member is attached so that the notch is located in the lower part where the drain of the steam introducing port is accumulated.

It is preferable that the drain introducing member is formed of a cutaway disk in which the cutaway portion is formed.

It is preferable that the cutaway portion of the drain introducing member is formed in a straight line, and is formed in an arc shape with an inner wall surface of the steam introducing port.

Preferably, the drain introducing member can be attached at different angles around the central axis of the steam introducing port.

The drain introducing member is a quadrangular attachment hole engaged with an octagonal boss formed on a wall surface of the first chamber of the casing and a wall of the first chamber on the side of the first chamber of the second chamber. It is preferable to have

The first chamber is
An intermediate chamber facing the suction port of the nozzle;
A high pressure chamber in communication with the steam inlet;
It consists of a communicating hole which connects the above-mentioned middle chamber and the above-mentioned high pressure chamber,
It is preferable that the cutaway portion of the drain introducing member faces an inflow port of the communication hole.

It is preferable that the notch of the drain introducing member faces the lower half of the inlet of the communication hole.

The housing comprises a main body forming the first chamber and a lid forming the second chamber,
It is preferable that a seal concave portion and a seal convex portion are formed in the main body portion and the lid portion by metal touch.

According to the present invention, the steam introducing port of the first chamber is provided with the drain introducing member having the notched portion, and the notched portion is attached to the lower portion where the drain of the steam introducing port is accumulated. The steam at the steam inlet is prevented from flowing to the inlet to the nozzle, and the drain is preferentially guided to the inlet to the nozzle.
In addition, since the main body portion of the housing and the lid portion are sealed by the seal concave portion and the seal convex portion which are fitted by metal touch, there is no steam leakage due to deterioration of the seal member, and the seal member is not used. The burden of periodic inspection and replacement work of the material is eliminated.
Furthermore, since the steam leak from the nozzle and the seal part is reduced, the fuel cost and the CO ₂ emission of the steam plant can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS The external appearance perspective view of the steam trap by embodiment of this invention. The disassembled perspective view of the steam trap of FIG. The disassembled sectional view of the steam trap of FIG. IV-IV sectional view taken on the line of FIG. Sectional drawing which shows the seal structure of a main-body part and a lid part. The perspective view (a) seen from the upper part of the nozzle, the perspective view (b) seen from the lower part, and a sectional view (c). The perspective view (a) and sectional drawing (b) of a drain introducing member. Sectional drawing (a) which shows the 1st attachment state of a drain introduction member, sectional drawing (b) which shows a 2nd attachment state, and sectional drawing (c) which shows the 3rd attachment state of a drain introduction member. Sectional drawing which shows the operation | movement of a steam trap. Sectional drawing which shows the flow of the suction part of a nozzle. The disassembled perspective view which shows the conventional steam trap.

FIG. 1 is an external perspective view of a nozzle type steam trap according to the present embodiment. The steam trap 1 has a housing 2, a steam inlet 3, and a drain outlet 4, and is a high temperature / high pressure steam introduced from the steam inlet 3, that is, a gas phase (steam) and a liquid phase The fluid in the state of coexistence with water is treated and discharged from the drain outlet 4 as liquid phased drain (water). The housing 2 is formed of metal such as stainless steel or cast iron, and the steam inlet 3 and the drain outlet 4 are provided coaxially. A branch pipe of a steam piping system for transporting steam generated by a boiler or the like in a plant facility is attached to the steam introduction port 3. Further, a drain pipe for discharging the drain to the outside is attached to the drain discharge port 4. By installing a plurality of steam traps 1 at appropriate intervals in the steam piping system, it is possible to effectively remove from the steam piping system unnecessary drains that have released latent heat and lost the inherent work capacity of steam. At the same time, the pressure of the steam piping system can be maintained in a dry state.

FIG. 2 is an exploded perspective view of the steam trap 1. The housing 2 is vertically divided into two parts, and has a main body 5 and a lid 6. The main body 5 and the lid 6 are integrated by a plurality of bolts (not shown). As shown in FIG. 3, a high pressure chamber 5 a in communication with the steam inlet 3 and a discharge chamber 5 b in communication with the drain discharge port 4 are provided inside the main body 5. These

chambers

5a and 5b are mutually divided via the division wall 5c which makes a part of main-body part 5 (casing 2). As shown in FIG. 4, the main body 5 is provided with a pair of openings 5 d orthogonal to the direction connecting the steam inlet 3 and the drain outlet 4. And the closure plug 5e is detachably attached to these opening parts 5d. A communication portion 5f is provided in the upper portion of the high pressure chamber 5a, and a communication port 5g is provided in the upper portion of the discharge chamber 5b.

As shown in FIG. 3, an intermediate chamber 5 h having a diameter smaller than that of the communication portion 5 f is provided at the back of the communication portion 5 f. The intermediate chamber 5h is in communication with the high pressure chamber 5a via a communication hole 5i bent in an L shape. The lowest portion of the drain inflow port on the high pressure chamber 5a side of the communication hole 5i coincides with the lowest portion of the high pressure chamber 5a. The opening 5d is in communication with the intermediate chamber 5h via the communication hole 5j, as shown in FIG. When the drainage valve or the ball valve is attached to the steam trap 1 and used, the closure plug 5e of one of the openings 5d is removed, and the drainage valve or the ball valve is attached to the exposed opening 5d. The drainage valve and the ball valve are used to quickly drain a large amount of drain generated in the steam piping at the time of shutdown (cold condition) of the factory facility and at the time of rising from the shutdown state.

On the upper surface of the main body 5, as shown in FIG. 2, a seal recess 5k is formed extending in an oval shape so as to surround the communication portion 5f and the communication port 5g. A luer taper is provided on the side surface of the seal recess 5k.

A detachable nozzle 7 for closing the communication portion 5f is attached to the communication portion 5f opened on the upper surface of the main body portion 5 via a circular net-like strainer 7b to close the intermediate chamber 5h. Specifically, an inner thread is formed on the inner peripheral surface of the communication portion 5 f, and an outer thread is formed on the outer peripheral surface of the nozzle 7. By screwing these inner and outer screws, the nozzle 7 is engaged with the communication portion 5f, and the communication portion 5f is closed. In the nozzle 7, a nozzle hole 7a that plays a central role in draining the steam to be treated by the steam trap 1 is integrally formed. The nozzle hole 7a is a nozzle 7 having a substantially cylindrical shape. It penetrates the central axis up and down.

As shown in FIGS. 2 and 3, a space including a low pressure chamber 6 a is provided inside the lid 6. The lid portion 6 is formed with a seal convex portion 6b extending in an oval shape so as to surround the low pressure chamber 6a. A luer taper is provided on the side surface of the seal convex portion 6b. As shown in FIG. 5, in the state where the lid 6 is assembled to the upper part of the main body 5, the gap between the main body 5 and the lid 6 is a fit of the metal touch between the seal recess 5 k and the seal protrusion 6 b. It is closed by the case. As a result, the low pressure chamber 6a becomes one compartment in which no fluid leaks.

As shown in FIG. 6, a substantially cylindrical recessed portion 7c is provided at an end on the suction port side of the nozzle hole 7a of the nozzle 7, that is, an end that forms a part of a wall that divides the high pressure chamber 5a. It is done. As shown in FIG. 6C, the depressed portion 7c has a cylindrical wall 7d having the same inner diameter as the inner diameter of the intermediate chamber 5h, a corner 7e having a curved surface positioned behind the suction port of the nozzle hole 7a, and the corner It has a continuous cross-sectional shape including an inclined portion 7f extending from the portion 7e toward the suction port of the nozzle hole 7a and a central portion 7g smoothly continuous from the inclined portion 7f to the suction port of the nozzle hole 7a. The angle θ of the inclined portion 7f with respect to the plane orthogonal to the center line of the nozzle hole 7a is preferably 20 to 40 °.

As shown in FIG. 3, a drain introducing member 8 is attached to the high pressure chamber 5 a inside the steam introducing hole 3. As shown in FIG. 7, the drain introducing member 8 is provided with a cutaway disk 8 b having the same diameter as the inner diameter of the high pressure chamber 5 a and partially having a cutaway portion 8 a. As shown in FIG. 8A, the cutaway portion 8a is formed in a straight line, and is formed in an arc shape with the inner wall surface of the high pressure chamber 5a. The cutaway portion 8a of the cutaway disk 8b is formed to face approximately the lower half of the drain inflow port on the high pressure chamber 5a side of the communication hole 5i. The notch 8a is not limited to a linear shape, and may be an arc shape or a semicircular shape. A circular mounting seat 8c is formed on one surface of the disc 8b to be in contact with the wall surface on the high pressure chamber 5a side, and a projection 8d having an external screw formed on the outer periphery is formed on the other surface. . The mounting seat 8c is provided with a mounting hole 8e having a square cross section, and the protrusion 8d is provided with a screw insertion hole 8f having a circular cross section communicating with the mounting hole 8e. The mounting hole 8e is adapted to engage with an octagonal boss 5l formed on the wall of the section wall 5c on the high pressure chamber 5a side.

The drain introducing member 8 inserts the mounting screw 8g into the screw insertion hole 8f and the mounting hole 8e, and screws it into the screw hole 5m formed in the octagonal boss 5l of the dividing wall 5c, thereby the high pressure chamber of the dividing wall 5c. It is attached to the wall on the 5a side. As shown in FIG. 8A, the notch 8a is horizontal as shown in FIG. 8A by rotating the notch disc 8b of the drain introducing member 8 around the central axis of the steam introduction port 3 and changing the angle of the notch disc 8b. As shown in FIG. 8 (b), the chipped portion 8a can be positioned at an angle of 45 degrees. Further, as shown in FIG. 8C, when the steam trap 1 is attached vertically, the chipped portion 8a is positioned at a lower portion where the drain of the steam introduction hole 3 is accumulated. In this case, the drain that has passed through the notch 8a flows into the drain inlet of the communication hole 5i through the gap 9 (see FIG. 9) between the drain introducing member 8 and the wall surface of the divided wall 5c on the high pressure chamber 5a side. Do.

Next, the operation of the steam trap 1 will be described.

FIG. 9 is a cross-sectional view of the steam trap 1. The flow path of the fluid introduced from the steam introduction port 3 is the high pressure chamber 5a, the notch 8a of the drain introduction member 8, the communication hole 5i, the intermediate chamber 5h, the strainer 7b, the nozzle hole 7a, the low pressure chamber 6a, the communication port 5g, It passes through the discharge chamber 5 b in order and is discharged from the drain discharge port 4. Here, a part of the wall part which divides intermediate chamber 5h is constituted by nozzle 7, and the suction mouth of nozzle hole 7a formed in this nozzle 7 has faced in high pressure chamber 5a. Moreover, about the low pressure chamber 6a located in the downstream of the high pressure chamber 5a, a part of the wall part which divides this is also comprised by the nozzle 7, The injection opening of the nozzle hole 7a formed in this nozzle 7 is low pressure It faces in the chamber 6a. Although the drawing shows a state where the suction port of the nozzle hole 7a is downward and the injection port is upward, the steam trap 1 is useless for top and bottom, and the nozzle hole 7a is directed in any direction. Even as the steam trap 1, it functions effectively.

On the other hand, the low pressure chamber 6a is in communication with the drain discharge port 4 through the communication port 5g and the discharge chamber 5b, and is maintained at an equivalent pressure (low pressure) to the atmospheric pressure. As a result, a pressure difference occurs between the high pressure chamber 5a and the intermediate chamber 5h into which the high temperature and high pressure steam is introduced, and the low pressure chamber 6a opened to the atmospheric pressure. The high pressure chamber 5a and the intermediate chamber 5h have substantially the same pressure.

Steam in the high pressure chamber 5a is blocked by the disc 8b of the drain introducing member 8 from flowing in from the drain inlet of the communication hole 5i. The drain collected in the lower part of the high pressure chamber 5a is introduced into the drain inflow port of the communication hole 5i through the notch 8a of the drain introducing member 8, and flows into the intermediate chamber 5h through the communication hole 5i. As described above, the drain introducing member 8 does not release the steam in the high pressure chamber 5a, and only the drain accumulated in the high pressure chamber 5a is preferentially supplied through the notch 8a of the drain introducing member 8 as an inlet of the communication hole 5i. To the intermediate chamber 5h, steam leakage can be prevented.

In a cold area, the drain in the high pressure chamber 5a is frozen at the time of operation stop, so the drain may not be discharged. Therefore, as shown in FIG. 8 (b), the drain introducing member 8 is attached to the steam trap 1 for cold regions so that the notch 8a is directed obliquely at 45 ° or in the vertical direction, and the steam trap 1 is mounted on the top of the notch 8a. The steam introduced from the opening 5d can be introduced to melt the frozen drain.

The nozzle hole 7a sucks the fluid in the high pressure chamber 5a and the intermediate chamber 5h from the suction port based on the pressure difference between the high pressure chamber 5a and the intermediate chamber 5h and the low pressure chamber 6a, and draws the sucked fluid to the low pressure Spray into the chamber 6a. At this time, since the upstream side strainer 7b covers the suction port of the nozzle hole 7a, dust in the fluid is removed prior to the flow into the nozzle hole 7a. Then, the fluid jetted from the nozzle hole 7a is cooled in the low pressure chamber 6a and becomes a drained liquid. The drain in the low pressure chamber 6 a flows into the downstream discharge chamber 5 b via the communication port 5 g and is then discharged to the outside from the drain outlet 4.

FIG. 10 is an explanatory view of the flow of fluid in the intermediate chamber 5h. First, when the fluid passing through the strainer 7b flows from the wide passage into the narrow nozzle hole 7a of the passage, an ejector effect occurs in the space A, and an action to draw the surrounding fluid occurs. On the other hand, the fluid in the space B in the vicinity of the inner peripheral wall of the intermediate chamber 5h flows along the curved surface of the depressed portion 7c by the Coanda effect to be rectified, and is drawn to the suction port of the central nozzle hole 7a by the ejector effect. The ejector effect is a phenomenon in which a low pressure space is generated by accelerating a fluid, and the fluid is drawn. The Coanda effect is a property of a fluid in which a fluid (turbulence) is rectified to flow along a curved surface of a wall when there is a curved wall by the fluid. The periphery of the suction port of the nozzle hole 7a is gently recessed concentrically with respect to the suction port, and thus the fluid having the flow disordered is rectified and led to the suction port of the nozzle hole 7a. Thus, the fluid flowing through the nozzle holes 7a is amplified and accelerated by the amount of the fluid rectified along the curved surface shape of the wall. As a result, when the pressure difference between the high-pressure chamber 5a and the low-pressure chamber 6a is the same, the injection amount of the nozzle holes 7a is larger in the configuration in which the wall is curved than in the configuration in which the wall is not curved.

As described above, according to the present embodiment, the drain introducing member 8 is attached to the high pressure chamber 5 a inside the steam introducing hole 3, and the drain introducing member 8 prevents the steam in the high pressure chamber 5 a from being released. Since only the drain collected in the chamber 5a is preferentially led to the inlet of the communication hole 5i and sent to the intermediate chamber 5h, it is possible to prevent steam leakage.

Moreover, according to the present embodiment, the periphery of the suction port of the nozzle hole 7a is gently recessed concentrically, and the fluid flows along the curved surface shape, so the nozzle hole is formed by the above-described ejector effect and Coanda effect. The fluid drawn into 7a is amplified and accelerated. As a result, the cooling capacity of the fluid is enhanced, so that the fluid is reliably phased and can be effectively drained.

The present invention is not limited to the above embodiments, and can be variously modified within the scope of the invention described in the claims. For example, the main body portion may be provided with a seal convex portion, and the lid portion may be provided with a seal concave portion.

In addition, the cooling capacity of the fluid in the nozzle type steam trap has a correlation with the amount and speed of the fluid ejected from the nozzle, and the larger the number, the finer the atomized fluid (atomized), The reduction efficiency to However, conventionally, little attention has been paid to enhancing the cooling capacity of the fluid.

Therefore, in order to enhance the cooling capacity of the fluid discharged from the nozzle type steam trap, the following measures can be taken.

[Means 1]
In the nozzle type steam trap,
And
A nozzle provided in the housing and having a nozzle hole;
A first chamber provided in the housing and facing the suction port of the nozzle hole;
And a second chamber provided in the housing and facing the injection port of the nozzle hole,
A nozzle type steam trap having a recessed portion gently recessed concentrically with the suction port at an end portion on a suction port side of a nozzle hole of the nozzle.
[Means 2]
The first chamber has an intermediate chamber facing the suction port of the nozzle hole,
The depression is
A cylindrical wall of the same inner diameter as the intermediate chamber and the inner diameter,
A corner made of a curved surface located behind the suction port of the nozzle hole;
An inclined portion extending from the corner toward the suction port of the nozzle hole;
The nozzle type steam trap of the means 1 which consists of a continuous curved surface which consists of a center part which continued smoothly from the said inclination part to the suction opening of a nozzle hole.
[Means 3]
The nozzle type steam and wrap of the means 2, wherein the angle of the inclined portion with respect to a plane orthogonal to the center line of the nozzle hole is 20 to 40 °.

According to the above-described means, the periphery of the suction port of the nozzle is gently recessed concentrically, and the fluid flows along the curved surface shape, so that the fluid attracted to the nozzle is amplified by the ejector effect and the Coanda effect.・ Speed up. As a result, the cooling capacity of the fluid is enhanced, so that the fluid is reliably phased and can be effectively drained.

DESCRIPTION OF SYMBOLS 1 steam trap 2 case 3 steam introduction port 4 drain discharge port 5 main body 5a high pressure chamber

5b discharge chamber

5c division wall 5d opening

5e closing plug

5f communication part

5g communication port 5h middle chamber

5i communication hole

5j communication hole 5k seal recess 5 l boss 5 m screw hole 6 lid body 6 a low pressure chamber 6 b seal convex portion 7 nozzle 7 a nozzle hole 7 b strainer 7 c recessed portion 7 d cylindrical wall 7 e corner portion 7 f inclined portion 7 g central portion 8 drain introducing member 8 a notched portion 8 b notched disk 8 c Mounting seat 8d Projection 8e Mounting hole 8f Screw insertion hole 8g Mounting screw 9 Clearance

Claims

In the nozzle type steam trap,
And
A nozzle provided in the housing;
A first chamber provided in the housing and facing the suction port of the nozzle;
A second chamber provided in the housing and facing the injection port of the nozzle;
And a drain introducing member provided at the steam introducing port of the first chamber and having a notch formed therein,
The nozzle-type steam trap, wherein the drain introducing member is attached so that the notch portion is located at a lower portion where the drain of the steam introducing port is accumulated.
The nozzle-type steam trap according to claim 1, wherein the drain introducing member is formed of a cutaway disk in which the cutaway portion is formed.
The nozzle-type steam trap according to claim 2, wherein the notch portion of the drain introducing member is formed in a straight line, and is formed in an arc shape with an inner wall surface of the steam introducing port.
The nozzle type steam trap according to claim 3, wherein the drain introducing member is attachable at different angles around a central axis of the steam introducing port.
The drain introducing member is a quadrangular attachment hole engaged with an octagonal boss formed on a wall surface of the first chamber of the casing and a wall of the first chamber on the side of the first chamber of the second chamber. The nozzle type steam trap according to claim 4, characterized in that:
The first chamber is
An intermediate chamber facing the suction port of the nozzle;
A high pressure chamber in communication with the steam inlet;
It consists of a communicating hole which connects the above-mentioned middle chamber and the above-mentioned high pressure chamber,
The nozzle-type steam trap according to any one of claims 1 to 5, wherein the notch portion of the drain introducing member faces an inflow port of the communication hole.
The nozzle-type steam trap according to claim 6, wherein the notch of the drain introducing member faces the lower half of the inflow port of the communication hole.
The housing comprises a main body forming the first chamber and a lid forming the second chamber,
The nozzle type steam trap according to any one of claims 1 to 7, wherein a seal concave portion and a seal convex portion which are fitted to each other by metal touch are formed in the main body portion and the lid portion.