JP2934935B2 - Valve with bypass piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve with a bypass pipe provided in building equipment, refuse incineration equipment, factory equipment, and the like.

[0002]

2. Description of the Related Art FIG. 10 is a schematic view of a conventional valve with a bypass pipe. In the figure, 1 is a valve body connected to a main pipe, 2 is a bypass pipe provided in this valve,
3 is a bypass valve. For example, when the main pipe and the valve 1 have a large diameter of 100 A or more, sudden opening and closing of the valve 1 of the main pipe causes a sudden flow of fluid to the secondary side, which adversely affects the pipe such as a water hammer and thermal shock. For this purpose, first, the bypass valve 3 of the bypass pipe is opened to gradually increase the flow rate, or the valve 1 is closed and then the bypass valve 3
In order to close the valve and gradually reduce the flow rate so as not to adversely affect the pipe, a bypass pipe connecting the inlet side and the outlet side of the valve body is provided. As shown in FIG. 11, a mounting portion of the valve box and the bypass pipe of the valve with the bypass pipe is provided with
0 was screwed on, and then the periphery of the bush 110 was welded to the outer surface of the valve box 4. The bypass pipe 2 is welded to the end of the bush 110, and the bypass pipe 2 is attached to the valve box 4.

[0003]

However, when the valve box 4 is made of a casting material such as cast iron, a normal welding rod for steel cannot be used. Welding must be peened with a hammer to remove welding stress, and the next weld must be repeatedly welded in the same manner, and carefully welded so that no residual stress remains in the valve box casting material There was a problem. Furthermore, in order to completely remove the stress in the welded portion, it is necessary to put the valve box 4 in a large heat treatment furnace after welding the bush 110 and perform annealing for removing the welding stress, which requires a great deal of labor and energy. In addition, the bypass pipe mounting portion of the normal valve box is located in a narrow portion having a complicated shape such as a valve box flange, and welding work is extremely difficult because a welding rod is difficult to enter.

In addition, since the bypass pipe 2 is completely fixed to the valve box 4 by welding, if a leak occurs from the welded portion, the leak cannot be completely prevented, and the welding is performed again or the valve valve box is replaced. The maintenance work also required a lot of man-hours, such as re-installing the bypass piping from the beginning.

Therefore, the present invention is caused by difficulties in welding work with a casting material having a complicated shape, a work for removing stress at a welded portion caused by welding, a difficulty in maintenance work in case of leakage, and a thermal expansion effect due to welding. It is an object of the present invention to provide a valve with a bypass pipe which can reduce the manufacturing cost by solving the deterioration of the sealing performance of the valve box valve itself.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention is a valve provided with a bypass pipe communicating between an inlet and an outlet of a valve valve box. And an inner seal portion provided on the inner surface side of the valve box of the through hole,
An adapter provided with a male screw inserted into the through hole of the valve box and an outer seal portion engaged with the inner seal portion of the valve box is mounted from the inner surface side of the valve box, and the adapter is mounted outside the valve box. A valve with a bypass pipe, wherein a nut is screwed into a screw, an adapter is fastened to the valve box, and a bypass pipe is connected to the adapter. Further, the inner seal portion of the valve box and the outer seal portion of the adapter are provided on the inner surface side of the valve box by 20 degrees to 18 degrees.
It can be provided on a sealing surface that extends at an angle of 0 degrees. A seal member such as a gasket may be provided between the inner seal portion of the valve box and the outer seal portion of the adapter. Further, the nut screwed into the external thread of the adapter may be provided with an elastic portion that repels with the outer surface of the valve box. Further, the second nut can be screwed onto the upper surface of the nut screwed to the external thread of the adapter via a disc spring to fasten the adapter to the valve box.

[0007]

According to the present invention, the outer seal portion of the adapter is engaged with the inner seal portion provided on the inner surface side of the valve box by the above-mentioned means and tightened by the nut on the outer surface of the valve box. Thus, the valve box and the adapter are fastened in a sealed state. By connecting the bypass pipe to the adapter fastened to the valve box by welding or the like, a valve with a bypass pipe provided with the bypass pipe in the valve box can be obtained. Since the welding between the adapter and the bypass pipe is performed at a position away from the valve box, the valve box made of a casting material is not affected by heat during welding. Therefore, since there is no portion to be directly welded to the valve box as in the prior art, various problems caused by welding to the surface of the valve box can be solved, the operation can be greatly simplified in manufacturing, and the manufacturing cost can be reduced.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 9 show a structure of a mounting portion of a valve with a bypass pipe in which a bypass pipe 2 is mounted on a valve box 4 according to an embodiment of the present invention. FIG. 1 shows a front view of a valve box 4 of a valve 1 showing a flange type gate valve. There is a valve seat 44 for opening and closing an inlet and an outlet in the center of the valve box. Two bypass seats 42 for mounting a bypass pipe are provided between the flange 43 and the flange 43.

FIG. 2 is a sectional view taken along the line A--A in FIG. 1. In the valve box 4, a through hole is provided in the bypass seat 42. An inner seal portion 46 is provided on the surface. The adapter 5 is mounted from the inner surface side of the valve box 4, and is provided with an outer seal portion 53 having a tapered surface similar to the inner seal portion 46 and a male screw 52.
The nut 5 is tightened from the outer surface side of the valve box 4 to fasten the adapter 5 to the valve box 4. Therefore, the outer seal portion 53 is pressed against the inner seal portion 46, and a large sealing surface pressure is generated to seal. Also, this seal portion is reliably sealed in combination with the fluid pressure in the valve box. Adapter 5 fastened to valve box
By connecting a bypass pipe 2 to the end of the valve by welding or the like, the valve 1 with a bypass pipe is formed. In addition, since welding of the bypass pipe 2 and the adapter 5 is usually made of carbon steel, there is no need to remove stress or the like.
Further, since the operation is performed at a position away from the surface of the valve box, there is no thermal influence on the valve box.

The tapered surfaces of the inner seal portion and the outer seal portion are finished to have a rough surface necessary for sealing the fluid inside the valve box, and a sealing agent is applied to the seal surface to improve the sealing performance. Is also good. Further, the seal portions 46 and 53 can be provided with a taper angle of 20 to 180 degrees for sealing, and the smaller the angle, the stronger the sealing surface pressure can be obtained. Further, as shown in FIG. 3, the seal portion taper angle between the valve box and the adapter may be 180 degrees, that is, a flat seat, and the gasket 8 may be sandwiched between the seal portions to seal the valve box 4 and the adapter 5. FIG. 4 shows the outer seal portion 53 of the adapter 5.
An example in which an annular groove 54 is provided to seal with the inner seal portion 46 of the valve box 4 is shown.
By forming the sealing portion 53 as a divided tapered surface, the sealing surface pressure is increased and the sealing performance is improved.

When a high-temperature fluid rapidly flows through the inside of the bypass pipe 2 at the initial stage of operation due to steam or high-temperature water or the like, the adapter 5 first undergoes thermal expansion and the heat transfer of the nut 6 is delayed, so that the nut 6 is delayed. The nut 6 may be loosened when an external factor such as vibration acts on the tightening force between the nut 6 and the valve box 4. As a countermeasure, the middle part of the adapter 5 may be lengthened as shown in FIG. 2 so that the nut 6 is given an elongation capable of absorbing thermal expansion in advance by tightening the nut 6. Specifically, the elastic area of the adapter is secured by making the length H dimension of the intermediate portion 51 of the adapter 5 of FIG. 2 longer than the screw diameter dN, and only the adapter 5 is heated to near the operating temperature during assembly. By quickly tightening the nut 6, loosening of the nut due to thermal expansion of the adapter can be solved.

FIG. 5 shows the nut 6 and the bypass seat 4 of the valve box.
2 shows an embodiment in which an elastic body 7 such as a disc spring is inserted between the adapter 5 and the thermal expansion of the adapter 5. FIG. 6 shows the nut 6
7 shows an embodiment in which a step portion 62 is provided on the lower surface of the nut and a groove 61 is provided on the inner peripheral side to prevent loosening, and a groove 63 is also provided on the outer periphery as shown in FIG. The thermal expansion of the adapter 5 may be absorbed to prevent the nut from loosening.
FIG. 8 shows an embodiment in which a disc spring 7 is attached to the lower surface of the nut 6, a spacer 9 is attached between the disc spring and the valve box, and the nut 6 is tightened. In this embodiment, the nut 6 can be fastened while avoiding obstacles such as ribs provided on the valve box. FIG. 9 shows an embodiment in which the disc spring 7 is inserted into the upper surface of the nut 6 and the flat washer 64 and the second nut 65 are provided to improve the nut locking effect. By adding the second nut 65, the locking effect is further improved. If external leakage occurs in the adapter and the valve box seal, the nut 6 can be further tightened to prevent leakage, and maintenance work can be easily performed.

[0012]

As described above, the valve with the bypass pipe according to the present invention has no residual stress generated at the time of welding and does not cause a problem affecting the sealing performance of the valve itself, so that a highly reliable valve can be obtained. Can be. In addition, maintenance work is easy and energy saving and cost reduction are achieved.

[Brief description of the drawings]

FIG. 1 is a front view of a valve valve box to which a bypass pipe according to an embodiment of the present invention is attached.

FIG. 2 is a cross-sectional view in which an adapter 5 is attached to an AA cross section of FIG.

FIG. 3 is a cross-sectional view showing an embodiment in which the seal portion of FIG. 2 is a flat seat.

FIG. 4 is an enlarged cross-sectional view showing another embodiment of the seal portion of FIG. 2;

FIG. 5 is an enlarged sectional view of a portion B in which an elastic member is mounted on the lower surface of the nut in FIG. 2;

FIG. 6 is an enlarged sectional view of a portion B in which an elastic portion is provided below a nut in FIG. 2;

FIG. 7 is an enlarged sectional view showing another embodiment of FIG. 6;

FIG. 8 is a sectional view showing an embodiment in which a spacer 9 is added.

FIG. 9 is a sectional view showing still another embodiment.

FIG. 10 is a conventional view schematically showing a valve with a bypass pipe.

FIG. 11 is a partial cross-sectional view showing a bypass pipe mounting portion of a conventional valve with a bypass pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve 2 Bypass piping 3 Bypass valve 4 Valve box 42 Bypass seat 46 Inner seal part 5 Adapter 53 Outer seal part 6 Nut 61, 63 Groove 62 Stepped part 7 Elastic body 8 Gasket 9 Spacer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 5-6262 (JP, U) JP-A 1-173578 (JP, U) JP 3-38532 (JP, Y2) (58) Survey Field (Int.Cl. ⁶ , DB name) F16K 27/00 F16L 41/08 F16L 19/00-19/08

Claims (5)

(57) [Claims] 1. A valve provided with a bypass pipe connecting an inlet side and an outlet side of a valve valve box on an outer wall of the valve box, wherein a through-hole and a valve in the through-hole are provided at a bypass pipe take-out portion of the valve box. An inner seal portion is provided on the inner surface side of the box, and an adapter provided with a male screw inserted into the through hole of the valve box and an outer seal portion engaged with the inner seal portion of the valve box is mounted from the inner side of the valve box. ,
Screwed valve nut to your screw of the adapter on the outside of the valve casing
A valve with a bypass pipe, characterized in that an adapter is fastened to the valve box while holding the outer wall of the box, and a bypass pipe is connected to the adapter. 2. A according to claim 1, wherein the the outer seal portion of the seal portion and the adapter of the valve body which is provided with sealing surfaces extending at an angle of 180 degrees from 20 degrees on the inner surface side of the valve body Valve with bypass piping. 3. The valve according to claim 1, wherein a seal member such as a gasket is provided between an inner seal portion of the valve box and an outer seal portion of the adapter. 4. The valve with a bypass pipe according to claim 1, wherein the nut screwed into the external thread of the adapter is provided with an elastic portion that repels between the nut and the outer surface of the valve box. 5. The valve with a bypass pipe according to claim 1, wherein a second nut is screwed on an upper surface of the nut screwed to the external thread of the adapter via a disc spring.