WO2021210572A1

WO2021210572A1 - Steam trap

Info

Publication number: WO2021210572A1
Application number: PCT/JP2021/015294
Authority: WO
Inventors: 芳彦伊能
Original assignee: 芳彦伊能; 日東礦工商事株式会社; 株式会社ゼットサービス
Priority date: 2020-04-14
Filing date: 2021-04-13
Publication date: 2021-10-21
Also published as: JP2021169830A; JP6886156B1

Abstract

[Problem] To provide a steam trap capable of preventing an increase in size and simplifying a structure and capable of reducing steam leakage to improve steam transport efficiency while quickly discharging condensed water generated by heat dissipation. [Problem] A steam trap 1 includes orifices 7, 9 which are disposed in the middle of a main steam transport pipe 110 that transports steam from a steam source to a steam supply target, are disposed inside a tubular body part 2, and have columnar holes 7C, 9C through which steam V and condensed water W generated by dissipating heat from the main steam transport pipe 110 pass, wherein the axial length L of the columnar holes 7C, 9C is defined by expression (1). Formula (1): L ≥ A/B, where L = axial length of columnar hole (mm), A = diameter of columnar hole (mm), B = assumed minimum load factor (%).

Description

steam trap

The present invention relates to a steam trap used by being provided in the middle of a steam transfer pipe provided in a steam transfer facility or at a condensed water outlet of a steam heating device facility such as a heat exchanger.

The steam trap, for example, when transporting steam in a steam transport facility, quickly discharges condensed water (also referred to as condensate or drain) generated by heat dissipation to the outside of the system, and transports the steam efficiently. It is placed in the middle of the pipe. This type of steam trap is disclosed in Patent Document 1. The steam trap disclosed in Patent Document 1 quickly discharges condensed water, which is high-temperature low-pressure condensate, and also reduces steam leakage.

In the trap casing of this steam trap, a needle valve is provided on the small diameter orifice side, and the opening degree of the small diameter orifice can be adjusted by moving the needle valve up and down. In addition, an on-off valve is installed on the entrance side of the communication passage so that it can move up and down. For this reason, the small-diameter orifice and the lower end of the communication passage form a valve chamber, and the valve chamber, the needle valve, the on-off valve, and the like are formed so as to project diagonally downward from the lower part of the trap casing. For this reason, the size of the steam trap is large.

By pulling down the needle valve to fully open the small diameter orifice and closing the on-off valve to close the connecting path, the condensate that flows in from the trap casing inlet collects in the valve chamber and passes through the small diameter orifice to the trap casing outlet. Is discharged to the outside. As a result, leakage of steam can be suppressed. When the amount of condensate flowing in from the inlet of the trap casing is small, the needle valve is pushed upward to reduce the passage area of the small-diameter orifice, so that only the condensate is discharged to the outside without leaking steam. Can be discharged.

When the steam pressure is low and a large amount of low-pressure condensate flows in, such as at the time of initial startup of steam-using equipment, this large amount of condensate can be removed by pulling down the on-off valve and opening the communication passage. It can be quickly discharged to the outside.

Japanese Unexamined Patent Publication No. 2001-50488

By the way, in the trap casing of the steam trap disclosed in Patent Document 1, it is necessary to arrange a small-diameter orifice, a communication passage, a needle valve that moves up and down, an on-off valve that moves up and down, and a valve chamber. For this reason, the steam trap has a structural portion that protrudes toward the outside of the steam pipe, so that the size is increased. Moreover, in order to suppress steam leakage while promptly discharging the condensate (drain, condensed water) generated by the heat dissipation of the steam pipe, the needle valve and on-off valve must be operated, and the trap casing must be operated. The structure is complicated.

The present invention has been made to solve the above problems, and it is possible to prevent an increase in size and simplify the structure, and while promptly discharging the condensed water generated by heat dissipation, the leakage of steam is reduced. It is an object of the present invention to provide a steam trap capable of increasing steam transfer efficiency.

The steam trap according to the first aspect of the present invention for solving the above problems is a steam trap arranged in the middle of a transport pipe for transporting steam from a steam source to a steam supply target.
Tube-shaped body and
It is provided in the main body portion and includes the steam and an orifice having a columnar hole for passing condensed water generated by heat dissipation of the transport pipe.
The axial length L of the columnar hole is defined by the following equation (1).

L ≧ A / B ・・・ Equation (1)

L = Axial length (mm) of the columnar hole
A = Diameter of the columnar hole (mm)
B = assumed minimum load factor (%)

Here, the diameter A of the columnar hole is designed so that the amount of the condensed water discharged due to the differential pressure before and after the installation portion of the transport pipe in which the steam trap is installed is equal to the required maximum discharge amount. Diameter,
The assumed minimum load factor B is the ratio of the minimum load assumed by the fluctuation of the heating load to the amount of the condensed water discharged due to the differential pressure before and after the installation site of the transport pipe in which the steam trap is installed. [Assumed minimum load (kg / h) / Assumed maximum load (kg / h)]

It is characterized by that.

According to the above configuration, since it is sufficient to adopt a structure in which the orifice is arranged in the tubular main body, it is possible to prevent the steam trap from becoming large and to simplify the structure of the steam trap. Since the axial length L of the columnar hole is defined by the equation (1), it prevents the condensed water generated by heat dissipation from collapsing, promptly discharges the condensed water, and reduces steam leakage. Therefore, the steam transfer efficiency and the heating efficiency can be increased.

Further, the steam trap of the second aspect of the present invention is characterized in that one or more of the orifices are arranged in the main body portion.
According to the above configuration, the number of orifices arranged in the main body can be arbitrarily set as needed, and the degree of freedom in design is increased.

Further, in the steam trap of the third aspect of the present invention, a plurality of the orifices are arranged in series in the main body portion, and the steam trap in the main body portion is in the direction in which the steam flows with respect to the plurality of the orifices. An overtaking suppression orifice for suppressing the phenomenon in which the flow of steam overtakes the flow of condensed water is arranged on the upstream side.
According to the above configuration, since the overtaking suppression orifice is arranged upstream of the plurality of orifices in the direction of steam flow, the steam flow does not flow before the flow of condensed water, and the condensed water does not flow. Since the steam flow is generated following the flow, it is possible to reduce the leakage of steam while promptly discharging the condensed water.

Further, the steam trap according to the fourth aspect of the present invention is characterized in that one of the orifices is provided with a plurality of columnar holes so as to be parallel to the axial direction of the main body portion.
According to the above configuration, the orifice can have a plurality of columnar holes as required, which increases the degree of freedom in design.

According to the present invention, it is possible to prevent an increase in size and simplify the structure, and while promptly discharging condensed water generated by heat dissipation, it is possible to reduce steam leakage and improve steam transfer efficiency. Can be provided.

The figure which shows an example of the steam transfer equipment which comprises 1st Embodiment of the steam trap of this invention. A cross-sectional view taken along the axial direction showing an example of a preferable internal structure of the steam trap shown in FIG. An exploded cross section showing the components of a steam trap FIG. 3 shows only the cylindrical overtaking suppression orifice, the first outflow suppression orifice, the spacer, and the second outflow suppression orifice shown in FIG. Diagram showing the shape of the overtaking suppression orifice The figure which shows the operation example of condensed water and steam when the axial length L of a columnar hole is 10mm, 5mm, 2.5mm. A cross-sectional view similar to FIG. 3 showing another embodiment of the outflow suppression orifice used in the steam trap of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
(Steam transfer equipment 100)
FIG. 1 shows an example of a steam transfer facility including the first embodiment of the steam trap of the present invention. First, the steam transfer equipment 100 in which the steam trap 1 is used will be described. The steam transfer facility 100 shown in FIG. 1 recovers the steam boiler 101, the heating device 102 as a heating target (steam supply target) that heats with the steam V, and the condensed water W generated when the steam V is transported. The steam main transport pipe 110, the condensed water recovery pipe 120, and the condensed water supply pipe, which are connected to the ring water tank 103 for storing the steam, the steam boiler 101, and the heating device 102, and convey the steam V and the condensed water W. 121 and.

The steam boiler 101 transports and supplies steam V to the heating device 102 through the steam main transport pipe 110. As a result, the heating device 102 is heated to a predetermined temperature by the steam V and performs a predetermined work by the steam V. The condensed water W generated in the heating device 102 after the work of the heating device 102 is executed is recovered from the heating device 102 to the ring water tank 103 through the condensed water recovery pipe 120. The condensed water W stored in the ring water tank 103 is supplied to the steam boiler 101 through the condensed water supply pipe 121, and is reused to generate steam V. In the steam main transport pipe 110, the steam main transport pipe 110 dissipates heat, so that when the steam V is transported, condensed water W is generated in the steam main transport pipe 110. The steam trap 1 of the present embodiment is arranged in the middle of the steam main transfer pipe 110 in order to remove the condensed water W to the outside of the steam transfer system and transfer only the steam V to the heating device 102.

As shown in FIG. 1, the steam trap 1 is arranged in the middle of the steam main transport pipe 110 so that it can be detachably replaced. In FIG. 1, the installation position of the steam trap 1 is symbolically shown. In this type of steam transfer equipment 100, in order to promote energy saving, it is required not only to improve the efficiency of the steam boiler 101, for example, but also to improve the transfer efficiency of steam V by using the steam trap 1. .. That is, by arranging the steam trap 1 in the middle of the steam main transport pipe 110, the steam main transport pipe 110 is quickly discharged to the outside of the steam transport system while the condensed water W generated by the heat radiation of the steam main transport pipe 110 is quickly discharged. It is required to reduce the leakage of steam V passing through and improve the steam transfer efficiency.

Therefore, in the first embodiment of the present invention, the steam trap 1 can prevent the size of the steam trap 1 from becoming larger and simplify the structure as compared with the conventional steam trap, as will be described in detail below. Moreover, the steam trap 1 can quickly discharge the condensed water W generated by the heat radiation of the steam main transport pipe 110 as a steam pipe, while reducing the leakage of steam V passing through the steam main transport pipe 110. By doing so, the structure is such that the steam transfer efficiency can be improved.

FIG. 2 is a cross-sectional view taken along the axial direction showing a preferable example of the internal structure of the steam trap 1 shown in FIG.
As shown in FIG. 2, the steam main transport pipe 110 has a primary side union 111 and a secondary side union 112. The primary side union 111 and the secondary side union 112 are one and the other connecting portions for detachably attaching the steam trap 1. The steam trap 1 is detachably connected between the primary union 111 and the secondary union 112 so that the steam trap 1 can be replaced as needed. The primary union 111 has a connecting member 111B, a connecting screw 111C, and a packing 111D. Similarly, the opposite secondary union 112 has a connecting member 112B, a connecting screw 112C, and a packing 112D. The secondary union 112 has a connecting member 112B and a connecting screw 112C. The primary side union 111 is on the steam boiler 101 side (primary side) shown in FIG. 1, and the secondary side union 112 is arranged outside the steam transport system (secondary side).

(Structural example of steam trap 1)
A structural example of the steam trap 1 shown in FIG. 2 will be described with reference to FIG. FIG. 3 is an exploded cross-sectional view showing the components of the steam trap 1.
As shown in FIGS. 2 and 3, the steam trap 1 includes a tubular main body 2 (see FIG. 2), a drain intake portion 11, a drain discharge portion 12, an internal set screw member 3, and a spring washer. It has a flat washer 5, an overtaking suppression orifice 6, a first outflow suppression orifice 7, a spacer 8, a second outflow suppression orifice 9, and a packing 10. The drain intake unit 11 is a side that takes in steam V and condensed water W from the steam boiler 101 of FIG. The drain discharge unit 12 is a side that discharges steam V and condensed water W to the outside of the steam transport system.

As shown in FIG. 2, the convex portion 111G of the connecting member 111B of the first union 111 is fitted into the concave portion 11C of the drain intake portion 11 and closely adhered while sandwiching the packing 111D. The female screw 111F of the connecting screw 111C is screwed into the male screw 11B of the drain intake portion 11, so that the connecting member 111B and the drain intake portion 11 are detachably connected in an airtight state.
Similarly, the convex portion 112G of the connecting member 112B of the second union 112 is fitted into the concave portion 12C of the drain discharge portion 12 and closely adhered while sandwiching the packing 112D. The female screw 112F of the connecting screw 112C is screwed into the male screw 12B of the drain discharge portion 12, so that the connecting member 112B and the drain discharge portion 12 are detachably connected in an airtight state.

As shown in FIGS. 2 and 3, the inner end portion 11N of the drain intake portion 11 is fixed to the outer peripheral surface of one end portion 2B of the main body portion 2 by, for example, a fixing member 20 by welding or application of an adhesive. There is. The male threaded portion 3N of the internal settling screw member 3 is screwed into the female threaded portion 11N of the drain taking-in portion 11, so that the internal settling screw member 3 is fixed to the drain taking-in portion 11. As shown in FIG. 3, the drain intake portion 11 has an internal hole 11H, and the internal set screw member 3 has an

internal hole

3H, 3J, and a convex portion 3K. As shown in FIG. 2, the outer peripheral surface of the convex portion 3K is inserted so as to be in close contact with the inner peripheral surface of one end portion 2B of the main body portion 2. The inner diameter of the inner hole 11H is larger than the inner diameter of the inner hole 3J, and the inner diameter of the inner hole 3J is larger than the inner diameter of the inner hole 3H.

Further, as shown in FIGS. 2 and 3, the inner end portion 12N of the drain discharge portion 12 is attached to the outer peripheral surface of the other end portion 2C of the main body portion 2 by, for example, a fixing member 21 by welding or application of an adhesive. It is fixed. As shown in FIG. 3, the drain discharge unit 12 has an internal hole 12H. The inner diameter of the inner hole 12H is the same as the inner diameter of the inner hole 3H. The outer peripheral surface of the convex portion 12K of the drain discharge portion 12 is inserted so as to be in close contact with the inner peripheral surface of the other end portion 2C of the main body portion 2.

As shown in FIG. 2, the spring washer 4, the flat washer 5, the overtaking suppression orifice 6, the first outflow suppression orifice 7, the spacer 8, the second outflow suppression orifice 9, and the packing 10 shown in FIG. 3 are Inside the tubular main body 2, they are arranged in order and in series from one end 2B to the other end 2C. As shown in FIG. 2, each outer peripheral surface of the spring washer 4, the flat washer 5, the overtaking suppression orifice 6, the first outflow suppression orifice 7, the spacer 8, the second outflow suppression orifice 9, and the packing 10 is It is in close contact with the inner peripheral surface of the main body 2. Each of these members is made of a metal such as SUS, except for the packing 10.

As shown in FIG. 3, the outer diameters of the spring washer 4, the flat washer 5, the overtaking suppression orifice 6, the first outflow suppression orifice 7, the spacer 8, the second outflow suppression orifice 9, and the packing 10 are convex. It is the same as the outer diameter of the portion 3K and the convex portion 12K. The spring washer 4 and the flat washer 5 are arranged between the convex portion 3K and the overtaking suppression orifice 6, and the overtaking suppression orifice 6, the first outflow suppression orifice 7, the spacer 8, and the second outflow suppression orifice 9 are arranged. , The spring washer-4 urges the drain discharge portion 12 side with the packing 10 interposed therebetween.

FIG. 4 shows only the cylindrical overtaking suppression orifice 6 shown in FIG. 3, the first outflow suppression orifice 7, the spacer 8, and the second outflow suppression orifice 9. FIG. 5 shows the characteristic shape of the overtaking suppression orifice 6.

(Overtaking suppression orifice 6)
As shown in FIGS. 3 and 4, the overtaking suppression orifice 6 has an inlet hole 6B, an orifice hole 6C, an outlet hole 6D, and a recess 6F. The inner diameter of the inlet hole 6B and the inner diameter of the outlet hole 6D are the same, but the inner diameter of the recess 6F is larger than the inner diameter of the outlet hole 6D. Further, characteristically, the inner diameter of the orifice 6C is considerably smaller than the inner diameter of the inlet hole 6B, and the inner diameter of the orifice 6C is, for example, about 3 mm, but is not particularly limited.

Moreover, as shown in FIG. 5, the central axis CL2 of the orifice hole 6C is eccentric downward with respect to the central axis CL1 of the inlet hole 6B, the outlet hole 6D, and the recess 6F. In this way, the overtaking suppression orifice 6 suppresses the phenomenon that the steam flow overtakes or precedes the flow of the condensed water. That is, the diameter of the orifice hole 6C of the overtaking suppression orifice 6 is small, and since it is eccentric below the central axis, the condensed water W, which is heavier than the light steam V and exists at the lower position, is passed first. After that, by passing the steam V, it is possible to prevent the condensed water W from being transported overtaking the steam V. As a result, it is possible to suppress the phenomenon that a large amount of steam V overtakes the condensed water W which is a drain.

(1st outflow suppression orifice 7)
As shown in FIG. 4, the first outflow suppression orifice 7 has a convex portion 7B, a columnar hole 7C, and a concave portion 7D. The inner diameter of the concave portion 7D is larger than the inner diameter of the convex portion 7B, and the inner diameter of the columnar hole 7C is smaller than the inner diameter of the convex portion 7B and smaller than the inner diameter of the above-mentioned orifice 6C. In the first outflow suppression orifice 7, the positions of the central axes of the convex portion 7B, the columnar hole 7C, and the concave portion 7D are the same. As shown in FIG. 2, the convex portion 7B is fitted in close contact with the concave portion 6F of the overtaking suppression orifice 6. The first outflow suppression orifice 7 is also called an outflow suppression columnar orifice, and suppresses the outflow rate of steam V on the primary side.

(Spacer 8)
As shown in FIG. 4, the spacer 8 has a convex portion 8B, a guide hole 8C, and a concave portion 8D. The spacer 8 is a member for arranging the first outflow suppression orifice 7 and the second outflow suppression orifice 9 apart from each other. The inner diameter of the concave portion 8D is larger than the inner diameter of the convex portion 8B, and the inner diameter of the guide hole 8C is the same as the inner diameter of the convex portion 7B. In the spacer 8, the positions of the central axes of the convex portion 8B, the guide hole 8C, and the concave portion 8D are the same. As shown in FIG. 2, the convex portion 8B is fitted in close contact with the concave portion 7D of the first outflow suppression orifice 7. The spacer 8 is also referred to as a back pressure maintaining spacer, and maintains the pressure inside the spacer 8 higher than the pressure on the drain opening portion (condensed water opening portion) side when the load of the drain (condensed water W) is reduced.

(Second outflow suppression orifice 9)
As shown in FIG. 4, the shape of the second outflow suppression orifice 9 is similar to the shape of the first outflow suppression orifice 7. The second outflow suppression orifice 9 has a convex portion 9B, a columnar hole 9C, and a concave portion 9D. The inner diameter of the concave portion 9D is substantially the same as the inner diameter of the convex portion 9B, and the inner diameter of the columnar hole 9C is smaller than the inner diameter of the convex portion 9B. In the second outflow suppression orifice 9, the positions of the central axes of the convex portion 9B, the orifice 9C, and the concave portion 9D are the same. The diameter of the columnar hole 9C and the diameter of the columnar hole 7C are the same. As shown in FIG. 2, the convex portion 9B is closely fitted into the concave portion 8D of the spacer 8. The recess 9D is closely connected to the internal hole 12H of the drain discharge portion 12 via the packing 10. The second outflow suppression orifice 9 is also referred to as a back pressure maintenance spacer pressure maintenance orifice, and suppresses the outflow of steam W from the spacer 8 when the load of the drain (condensed water W) is reduced.

By the way, as shown in FIG. 1, when the steam V generated by the steam boiler 101 is supplied to the heating device 102 through the steam main transfer pipe 110, the heating capacity of the steam V for heating the heating device 102 is , It decreases due to "retention of condensed water W". The condensed water W is generated in the steam main transport pipe 110 when the steam main transport pipe 110 dissipates heat. The condensed water W is high-pressure hot water and is also called a water mass.

In order to prevent "retention of condensed water W" from occurring in the steam main transport pipe 110 shown in FIG. 1, the steam trap 1 has a discharge capacity of condensed water W and an outflow amount of steam V. Regarding the shapes of the columnar holes 7C of the first outflow suppression orifice 7 and the columnar holes 9C of the second outflow suppression orifice 9 described above so as to be able to be suppressed, in particular, the axial lengths L of the

columnar holes

7C and 9C are , Is defined by equation (1) as follows.

L ≧ A / B ・・・・・・・ Equation (1)

L = Axial length (mm) of

columnar holes

7C and 9C (orifice holes)
A = Diameter (mm) of

columnar holes

7C and 9C (orifice holes)
B = assumed minimum load factor (%)

Here, for the diameters (orifice diameters) A of the

columnar holes

7C and 9C, the maximum amount of condensed water W discharged due to the differential pressure before and after the installation site where the steam trap 1 is installed in the steam main transport pipe 110 is the maximum required. The diameter is designed to be equal to the emission amount.
Further, the assumed minimum load factor B is the minimum assumed by the heating load fluctuation and the like of the amount of condensed water W discharged due to the differential pressure before and after the installation site where the steam trap 1 is installed in the steam main transport pipe 110. Load ratio: [Assumed minimum load (kg / h) / Assumed maximum load (kg / h)] ・・%
Is.
The assumed minimum load factor B is generally 50%, but in the embodiment of the present invention, it is set to, for example, 20%.
In this way, in the

columnar holes

7C and 9C having a diameter A and a length L or more, water lumps that block the

columnar holes

7C and 9C by the condensed water W are generated at at least two places in the length direction of the

columnar holes

7C and 9C. Therefore, it is possible to prevent a large amount of steam V from flowing out and being sent.

The relationship between the axial length L of the columnar hole 7C of the first outflow suppression orifice 7 and the columnar hole 9C of the second outflow suppression orifice 9 and the diameter (orifice diameter) A of the

columnar holes

7C and 9C is expressed by the equation (1). ), When the

columnar holes

7C and 9C are small, only the condensed water W is sent and the required amount of steam V cannot be secured, or conversely, when the

columnar holes

7C and 9C are large. It is possible to prevent the condensed water W from collapsing and causing a large amount of steam V to flow out and be sent.

That is, the diameters A of the

columnar holes

7C and 9C should be appropriately set while accurately grasping the amount of condensed water W generated (drain generation amount), the pressure of steam V, and the pressure of steam condensed water on the discharge side. Then, in the steam main transport pipe 110 shown in FIG. 1, a wall of condensed water W is formed, and the required amount of steam V is insufficient to secure the required amount of steam V. It is possible to prevent a phenomenon in which the condensed water W cannot be supplied or, conversely, the wall of the condensed water W is not formed and the condensed water W collapses, causing a large amount of steam V to flow out to the heating device 102 side of FIG. By setting the length L of the

columnar holes

7C and 9C to preferably 5 mm or more, most preferably 10 mm or more, the outflow volume and outflow rate of the vapor V due to the load fluctuation can be predicted.

In this way, in the main body 2 shown in FIG. 2, the condensed water W is conveyed by the overtaking suppression orifice 6, the first outflow suppression orifice 7, the spacer 8, the second outflow suppression orifice 9, and the packing 10. A path is formed, and the condensed water W generated from the steam boiler 101 shown in FIG. 1 is passed through a steam trap 1 arranged in the middle of the steam main transport pipe 110 without damaging the condensed water W. The structure is such that the decrease in the supply amount of steam V for heating the heating device 102 is suppressed, and the steam V can be efficiently transported to the heating device 102.

(Operation example of steam trap 1)
Next, an operation example of the steam trap 1 will be described with reference to the figure.
From the steam boiler 101 shown in FIG. 1, steam V is supplied to the steam main transport pipe 110. The condensed water W is generated in the steam main transport pipe 110 due to heat dissipation from the steam main transport pipe 110. As shown in FIG. 2, the condensed water W includes an internal hole of the connecting member 111B of the primary union 111, an internal hole 11H of the drain intake portion 11, an

internal hole

3J, 3H of the internal washer screw member 3, and a spring. It reaches the overtaking suppression orifice 6 through the washer 4 and the flat washer 5.

As shown in FIG. 5, the central axis CL2 of the orifice hole 6C of the overtaking suppression orifice 6 is eccentric downward with respect to the central axis CL1 of the inlet hole 6B and the outlet hole 6D. Therefore, the condensed water W flows in the orifice hole 6C before the light steam V, and after the condensed water W flows, the steam V flows through the orifice hole 6C. That is, in the overtaking suppression orifice 6, the condensed water W is preceded and the steam V is sent after the condensed water W by suppressing the phenomenon that the flow of the steam V overtakes or precedes the flow of the condensed water W. As a result, it is possible to suppress the phenomenon that a large amount of steam W overtakes the condensed water V which is the drain and is sent first, and the steam V flows after the condensed water W flows.

Next, the flow of the condensed water W and the flow of the steam V behind the flow of the condensed water W are transferred from the overtaking suppression orifice 6 shown in FIG. 2 to the convex portion 7B of the first outflow suppression orifice 7 and the columnar hole. By passing through 7C and the recess 7D, the outflow rate of steam V on the primary side is suppressed. That is, the first outflow suppression orifice 7 is also referred to as an outflow suppression columnar orifice, and can suppress the outflow rate of steam V on the primary side.

As described above, even if the flow of the steam V behind the flow of the condensed water W passes through the columnar hole 7C of the first outflow suppression orifice 7 and is released in the recess 7D to become a low pressure, as described above. Since the axial length L of the columnar hole 7C is defined, at least one condensed water W (water mass) is always present in the columnar hole 7C, so that the total length of the columnar hole 7C is completely eliminated and condensed. Water W (water mass) does not collapse. That is, even if the flow of the steam V behind the flow of the condensed water W becomes low pressure in the recess 7D after passing through the columnar hole 7C, at least one condensed water is located on the upstream side (primary side) of the columnar hole 7C. Since W (water mass) exists, the condensed water W (water mass) does not collapse, and the flow of the steam V behind can be suppressed following the flow of the condensed water W.

The flow of steam V behind the flow of condensed water W passes through the guide hole 8C of the spacer 8 in FIG. 3 as it is. The spacer 8 is also referred to as a back pressure maintaining spacer, and maintains the pressure inside the spacer 8 higher than the pressure at the open portion of the drain (condensed water W) when the load of the drain (condensed water W) is reduced. Then, the flow of the steam V behind the flow of the condensed water W is formed from the concave portion 7D of the first outflow suppression orifice 7 in FIG. 3 to the convex portion 8B of the second outflow suppression orifice 8, the guide hole 8C, and the concave portion 8D. Go through in order.

The flow of steam V behind the flow of the condensed water W passes through the columnar hole 9C of the second outflow suppression orifice 9 in the same manner as in the case of the columnar hole 7C of the first outflow suppression orifice 7. As a result, the condensed water W (water mass) does not collapse even in the second outflow suppression orifice 9, and the flow of the steam V behind is suppressed following the flow of the condensed water W. The condensed water W and steam V that have passed through the columnar holes 9C and the recesses 9D of the second outflow suppression orifice 9 pass through the internal holes 12H of the drain discharge portion 12 while maintaining the state, and then the secondary union. It passes through 112 and is delivered to the secondary side.

Further, the operations in the

columnar holes

7C and 9C will be specifically described.
In the above formula (1), assuming that A =

columnar hole

7C, 9C (orifice hole) diameter (mm) is 1 mm, B = assumed minimum load factor (%) is 20%, L =

columnar hole

7C, 9C. When the axial length (mm) of (orifice hole) is obtained,
L ≧ A / B = 5mm
Will be.
The flow operation of the condensed water W and the steam V in the columnar holes in which L, A, and B are determined in this way will be described with reference to FIG.
6 (A) to 6 (C) show that (A) is equal to 10 mm, which is twice the calculated value of L, and (B) is equal to the calculated value of L, 5 mm, with respect to the axial length L of the columnar hole. An example of the flow operation of the condensed water W and the steam V when 5 mm and (C) are 2.5 mm having a half length shorter than the calculated value of 5 mm of L is schematically shown. 6 (A) and 6 (B) show the present embodiment satisfying the condition of the calculated value of L of 5 mm or more, and FIG. 6 (C) shows a comparative example in which the calculated value of L of 5 mm or more is not satisfied. ing. In the

columnar holes

7C and 9C having a diameter A of 1 mm, the condensed water W is formed as a water mass W (see the hatched portion in FIG. 6) having a film width (length) of 0.5 mm due to surface tension. Inside the columnar pores, one water mass W having a film width of 0.5 mm is formed in a length region having a pore length of 2.5 mm. Therefore, since L in the figure (A) is 10 mm, which is twice the calculated value of 5 mm, four water masses W are formed at intervals of 2.5 mm, and L in the figure (B) is equal to the calculated value of 5 mm. Since it is 5 mm, two water masses W are formed at intervals of 2.5 mm, and L in FIG. A mass W is formed.
In each of FIGS. 6 (A) to 6 (C), the water mass W is located on the most primary side where the steam pressure at the rightmost position acts in the columnar hole portion on the uppermost stage, and 4 in the columnar hole on the lower stage side. It shows a state in which the water mass W moves to the left secondary side (atmosphere side) by 0.5 mm, which is the same width as the water mass W, as it is displaced. The water mass W returns from the bottom to the top of each figure, and the same movement is repeated in order.
In particular, when the water mass W further advances to the left side on the secondary side from the state at the bottom of each figure (A) to (C), the water mass located on the leftmost part on the most secondary side of the columnar hole becomes. The steam V that was released to the secondary side and existed on the right side of the water mass W is released to the secondary side on the left side at once. After that, a new water mass W is formed on the rightmost side of the columnar hole on the most temporary side so as to return to the state of the uppermost stage of each figure (A) to (C).
When the moving state of the water mass W shifts from the bottom state to the top state in each figure (A) to (C), the water mass located at the leftmost part of the columnar hole is on the secondary side. At the moment when the water is released into the column, it is questioned whether the ability to suppress the movement of the steam V in the columnar holes of FIGS. (A) to (C) at a low speed is exhibited.
In the embodiment of the present invention shown in FIGS. 6A and 6B, since the length L of the columnar hole is 5 mm or more satisfying the above formula (1), at least two water masses W are inside the columnar hole. Therefore, even at the moment when the water mass W located on the leftmost side is discharged to the secondary side, another water mass W is surely present on the upstream side (right side) of the discharged water mass W. Therefore, it is surely prevented that the entire columnar hole is fully opened without the presence of the water mass W even for a moment and the steam V is discharged at high speed, and the leakage of the steam V is reduced. The steam transfer efficiency can be increased. In particular, when the secondary side on the left side of the columnar holes of FIGS. 6 (A) and 6 (B) is atmospheric pressure (atm), the leftmost water mass W is the uppermost stage of each of FIGS. It is predicted that each of the lowermost stages will also evaporate and disperse to the atmosphere side, but since another water mass W is surely present on the upstream side (right side) of the water mass W to be evaporated, the above Similarly, the leakage of steam V can be reduced and the steam transport efficiency can be improved.
However, in the comparative example of FIG. 6C, since there is only one water mass W inside the columnar hole, the moment the water mass located on the leftmost side is released to the secondary side, For a moment, it is predicted that there will be a problem that the water mass W does not exist over the entire columnar hole and the water mass W is fully opened and the steam V is discharged at high speed. Further, when the secondary side on the left side of the columnar hole in the figure (C) is atmospheric pressure (atm), only one water mass W existing inside the columnar hole is the uppermost stage in the figure (C). It is predicted that the vapor V will evaporate to the atmosphere side in each of the lowermost stages as well, and the problem that the steam V will be discharged at high speed will occur as described above.

As described above, in the present embodiment, as shown in FIG. 2, by applying the steam trap 1 to the steam main transfer pipe 110 of the steam transfer facility 100, at least two totals are provided in the tubular main body 2. The first outflow suppression orifice 7 and the second outflow suppression orifice 9 will be arranged in series. The steam trap 1 has a spring washer 4, a flat washer 5, an overtaking suppression orifice 6, a first outflow suppression orifice 7, a spacer 8, and a second outflow suppression orifice 9 in a tubular main body 2. A structure is adopted in which each component of the packing 10 is housed in series. Therefore, since the steam trap 1 of the present embodiment does not have a portion protruding outward from the main body 2, it is possible to prevent the steam trap from becoming larger and to simplify the structure as compared with the conventional steam trap. Further, since the condensed water W generated by the heat radiation of the steam main transport pipe 110 can be quickly discharged to the outside of the steam transport system, the leakage of steam V passing through the steam main transport pipe 110 can be reduced and supplied to the heating device 102. The steam transfer efficiency can be increased.

FIG. 7 shows another embodiment of the outflow control orifice of the steam trap of the present invention.
The outflow suppression orifice 17 of the present embodiment is provided with two

columnar holes

17C and 17C instead of the one columnar hole 7C in the outflow suppression orifice 7 of the above embodiment. The two

columnar holes

17C and 17C have the same total area of the

columnar holes

17C and 17C as the area of one columnar hole 7C. As a result, the two

columnar holes

17C and 17C satisfy L ≧ A / B in the formula (1) in total. The convex portion 17B, the columnar hole 7C, and the concave portion 17D, which have other configurations, are formed in the same manner as the outflow suppression orifice 7 of the embodiment.
The outflow suppression orifice 17 of the embodiment of FIG. 2 also exerts the same effect as that of the outflow suppression orifice 7 of the embodiment, and can reduce the leakage of steam V and improve the steam transfer efficiency. ..
Although the number of columnar holes of the orifice to be set is one as in the embodiment of FIG. 2 and two cases as in the embodiment of FIG. 7, further, the columnar holes of the orifice are set. The number may be 3 or more.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of claims.
For example, in the illustrated embodiment, two outflow suppression orifices such as the first outflow suppression orifice 7 and the second outflow suppression orifice 9 are arranged in series in the main body 2, but the present invention is not limited to this. One or three or more outflow suppression orifices may be provided in series.

1 Steam trap 2 Main body 3 Internal retainer screw member 4 Spring washer 5 Flat washer 6 Overtaking suppression orifice 7 First outflow suppression orifice 8 Spacer 9 Second outflow suppression orifice 10 Packing 11 Drain intake part 12 Drain discharge part 17 Outflow suppression orifice 100 Steam transfer equipment 110 Steam main transfer pipe (example of transfer pipe)
101 Steam boiler (example of steam source)
102 Heating equipment as a heating target (example of steam supply target)
111 1st Union 112 2nd Union

Claims

A steam trap placed in the middle of a transport pipe that transports steam from a steam source to a steam supply target.
Tube-shaped body and
An orifice arranged in the main body portion and having a columnar hole for passing the steam and condensed water generated by heat dissipation of the transport pipe is provided.
The axial length L of the columnar hole is defined by the following equation (1).

L ≧ A / B ・・・ Equation (1)

L = Axial length (mm) of the columnar hole
A = Diameter of the columnar hole (mm)
B = assumed minimum load factor (%)

Here, the diameter A of the columnar hole is designed so that the amount of the condensed water discharged due to the differential pressure before and after the installation portion of the transport pipe in which the steam trap is installed is equal to the required maximum discharge amount. Diameter,
The assumed minimum load factor B is the ratio of the minimum load assumed due to the fluctuation of the heating load, etc., of the amount of the condensed water discharged due to the differential pressure before and after the installation site of the transport pipe in which the steam trap is installed. Yes [Assumed minimum load (kg / h) / Assumed maximum load (kg / h)]

A steam trap that features that.
The steam trap according to claim 1, wherein one or more of the orifices are arranged in the main body portion.
A plurality of the orifices are arranged in series in the main body portion, and the steam flow is the condensed water on the upstream side in the main body portion in the direction in which the steam flows with respect to the plurality of orifices. The steam trap according to claim 1, wherein an overtaking suppression orifice for suppressing a flow overtaking phenomenon is arranged.
The steam trap according to any one of claims 1 to 3, wherein the one orifice is provided with a plurality of columnar holes so as to be parallel to the axial direction of the main body.