JP3585220B2 - Wafer type valve with centering mechanism - Google Patents

Description

[0001]
[Field of the Invention]
The present invention relates to a wafer-type valve that is sandwiched and mounted between pipe flanges, and in particular, a wafer-type valve having a centering mechanism that can easily and surely perform centering for aligning the center of the pipe with the valve. Related to valves.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a wafer type valve such as a butterfly valve which is sandwiched between pipe flanges and fastened and fixed with pipe bolts and nuts is known. Such a wafer-type valve requires that the center of the valve and the center of the pipe be exactly aligned with each other. If the two centers do not match, the sealing performance of the connection part will be impaired, cavitation will occur at the displaced step, and if the displacement is large, the rotating valve will interfere with the piping etc. There was a problem. Flange joints for pipes have different types and dimensions of fittings depending on the magnitude of pressure and different standards for each country, so it is necessary to make the dimensions of the valves connected to these fittings different to suit each fitting. It was not easy to match the center of the valve, that is, to accurately perform centering.
[0003]
A conventionally known centering method is to form a rib (3) capable of supporting a piping bolt (4) on a valve shaft (2) of a valve body (1), for example, as shown in FIG. There is known a method of centering by contacting and supporting a pipe bolt (4) with 3). However, such ribs are formed by a casting method due to the high cost of machining, but the molding accuracy is lower than the required centering accuracy. I couldn't get it, and the accuracy of center alignment had to depend on the skill of the skilled person. Further, since a single shape cannot be adapted to flanges of various standards, there is a problem that a plurality of molding dies must be prepared while having the same size and the same specifications. In order to avoid such a problem, Japanese Utility Model Publication No. 51-54247 discloses a valve in which a centering rib is provided as a separate part from the valve body so as to be commonly used for transport pipes of different sizes. However, in this centering structure, when piping the valve, it is necessary to insert the bolt while maintaining the pipe and the valve in an accurate center once, so that a plurality of operators are required and the valve is supported. Therefore, there is a problem that a suspension device such as a crane is required to increase the cost of piping work. In the centering method shown in FIG. 9 and Japanese Utility Model Publication No. 51-54247, when the valve is removed from the pipe, the valve cannot be pulled out from between the pipe flanges unless the centering bolt is completely removed. If this bolt is removed and the other bolts are loosened, the valve falls as shown in FIG. 11, and there is a danger that the operator's hand may be caught.
[0004]
Further, as shown in FIG. 10, a method is known in which a hole (5) is formed in a rib (3) formed in a valve stem so that a pipe bolt is inserted. According to this method, by providing a plurality of holes for bolt insertion, more accurate centering can be achieved than in the case of FIG. 9, but the problems shown in FIG. 9 and the Japanese Utility Model Publication No. 51-54247 and It has a similar problem. Japanese Patent Publication No. 47-9092 discloses a structure in which a rib protruding radially in the outer radial direction is provided on the outer peripheral surface of a valve body, and the rib is brought into contact with a pipe bolt to perform centering. However, such a structure has a drawback that it is not possible to cope with a plurality of flange standards having different dimensions.
[0005]
Japanese Utility Model Publication No. 3-39651 and Japanese Patent Application Laid-Open No. 8-285110 propose a centering method capable of coping with a plurality of different flange standards. In Japanese Utility Model Publication No. 3-39651, a long hole-shaped bolt insertion hole for pipe bolt insertion is formed in a valve body, and a cutable obstruction is provided in the bolt insertion hole. Japanese Patent Application Laid-Open No. 8-285110 discloses a structure in which a rib is annularly protruded from an outer peripheral edge of a synthetic resin valve body, and a cutable portion that can be cut is formed on the rib. There is disclosed a structure in which a plurality of flange standards can be met by cutting the cut portion. However, the structure disclosed in Japanese Utility Model Publication No. 3-39651 requires a bolt insertion work while centering the valve on the pipe as in the case of FIG. 10, so that a suspension device such as a crane is required, and the valve is connected to the pipe. When the bolt is pulled out to remove from the valve, there is a problem that the valve may fall. In the structure disclosed in Japanese Patent Application Laid-Open No. 8-285110, the cutout portion is provided with a notch so that the cutout can be easily cut off. Therefore, when the strength of the resection is increased, there is a risk that resection becomes difficult or a portion other than the resection is broken.
[0006]
[Problems to be solved by the invention]
With the present invention, the center of the pipe and the valve can be accurately matched, the work can be easily performed alone, and the mounting work and the removal work can be performed while supporting the valve with the pipe bolt. It's something you want.
[0007]
[Means for Solving the Problems]
Means adopted by the present invention to solve the above problem is that a pipe bolt is abutted at a predetermined interval on the outer peripheral surface of the valve body, and the center of the pipe matches the center of the valve by the abutment between the valve body and the pipe bolt. In a wafer type valve provided with a centering mechanism configured to perform centering, an arc-shaped concave portion extending in a width direction of the valve body is formed on an outer peripheral surface of a valve body abutting on a piping bolt, and the concave is formed. A releasable closing plate that is bridged substantially at the center of the portion is formed by casting integrally with the valve body, and the outer surface of the closing plate is formed at least flush with the outer peripheral surface of the valve body. The outer surface of the recess is closed .
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Preferred embodiments of the present invention will be described in detail below. According to the present invention, pipe bolts are brought into contact with the entire outer peripheral surface of the valve body at predetermined intervals, and by contact between the valve body and the pipe bolt, the center of the pipe and the valve can be made to coincide with each other. A recessed part whose outer surface is closed by a releasable closing plate is formed at the abutting position, and multiple flange standards are met by abutting the piping bolt and the closing plate or by inserting the piping bolt into the recessed part. It is characterized in that the valve can be attached to or detached from the pipe flange while supporting the lower half of the valve body with a pipe bolt inserted into the pipe flange. By aligning the center by the contact between the pipe bolt and the valve body to enable centering, skilled work is not required for centering work, and the lower half of the valve body is supported by the pipe bolt. By being able to attach and detach the valve while attaching it, it becomes possible for one operator to perform the attaching and detaching work of the valve.
[0009]
【Example】
Referring to FIGS. 1 and 2, the drawings show a butterfly valve to which the present invention is applied, but the present invention is not limited to such a butterfly valve. It will be readily understood by those skilled in the art that the present invention can be applied to a valve such as a wafer type check valve which is sandwiched and mounted between pipe flanges. According to the present invention, an arc-shaped concave portion (10) capable of receiving a pipe bolt (6) is formed at a predetermined interval on an outer peripheral surface of a valve body (1), and is formed on an outer surface of the concave portion (10). The recess (10) is closed with a closing plate (11) that is bridged in a bridge shape. As shown in FIG. 2, the concave portion (10) extends in the width direction of the valve body, and the closing plate (11) extends over the center of the concave portion (10) . The outer surface of the closing plate (11) is formed flush with the outer peripheral surface of the valve body (1). When the closing plate (11) is present, the recess (10) does not exist, and the piping bolt ( 6) corresponds to the flange standard corresponding to the outer peripheral surface of the valve body (1). When the closing plate (11) is cut off, the pipe bolt (6) can be received in the recess (10), and the flange standard conforms to the inner surface of the recess (10).
[0010]
The closing plate (11) is cast integrally with the valve body (1), and has a sufficient strength without a decrease in strength unlike the conventional cut-out portion, so that the closing plate (11) is connected to the pipe bolt (6). There is no risk of breakage due to contact. The closing plate (11) having sufficient strength is cut off at a factory using a processing machine such as a milling machine, a drilling machine, and a grinder. However, the processing position is clear and the processing precision is not required because it is merely shaved off. It can be processed in a short time. Although the outer surface of the closing plate (11) is formed flush with the outer peripheral surface of the valve body, it may be formed so as to project slightly outward. By doing so, a flange standard according to the outwardly projecting length, a flange standard in which the protruding portion is cut flush with the outer peripheral surface of the valve body, and a recessed portion (10) in which the closing plate is cut off It is also possible to correspond to three types of flange standards that match the inner surface of. In this case, since the cutting of the protruding portion is cutting to be flush with the outer peripheral surface of the valve body, the processing position is clearly shown, and processing accuracy is not particularly required.
[0011]
FIGS. 3 and 4 show a butterfly valve (8) centered by the centering device according to the present invention and attached between pipe flanges (7), which are tightened by a plurality of pipe bolts (6). ) Is sandwiched between. The piping bolts (6) are positioned at predetermined intervals on the entire outer peripheral surface of the valve body (1), and the center of the piping and the valve are aligned by the contact between the valve body (1) and the piping bolts. FIG. 3 shows a state in which the closing plate (11) has not been cut away, and the piping bolt (6) is in contact with the outer surface of the closing plate (11) as shown in FIG. When the closing plate (11) is cut off, the pipe bolt (6) enters the recess (10) and comes into contact with the inner end face of the recess as shown in FIG. 5 and 6 show a valve mounting operation by the centering device of the present invention. A piping bolt is inserted into the lower half of the piping flange, the butterfly valve is dropped from above, and the lower half of the valve body is connected with the piping bolt. To support. As a result, the outer peripheral surface of the lower half of the valve body (1) is supported in contact with the piping bolt, so that the valve body (1) and the piping flange can be centered. And secure it. When the valve is to be removed, the lower part of the valve body is supported by the lower part of the piping bolt, the upper part of the piping bolt is removed, and the valve is pulled out upward. As described above, since the valve can be attached or detached while supporting the lower portion of the valve body with the piping bolts, the operation can be performed by one worker, and the operation cost can be reduced.
[0012]
【The invention's effect】
According to the present invention, since the closing plate is cast integrally with the valve body and has sufficient strength, there is no possibility of breakage due to contact with the pipe bolt, and the closing plate has sufficient strength. Even when cutting off the closing plate, the processing position is clear and processing accuracy is not required, so that accurate processing can be performed in a short time. Further, since the recessed portion extends in the width direction of the valve body, the pipe bolt can be supported along the length direction thereof, and the contact state with the pipe bolt is stabilized.
[Brief description of the drawings]
1 is a front view of a butterfly valve body according to the present invention; FIG. 2 is an enlarged perspective view of a main part; FIG. 3 is a front view showing a mounted state; FIG. 4 is a side view showing the same; FIG. Front view [FIG. 6] Side view [FIG. 7] Cross-sectional view of the state where the closing plate and the pipe bolt are in contact [FIG. 8] Cross-sectional view of the state where the closing plate is inserted into the recessed portion [FIG. Front view showing one example [FIG. 10] Front view showing another conventional example [FIG. 11] Front view showing conventional defects [Explanation of reference numerals]
(1) Valve body (2) Valve stem (3) Rib (4) Piping bolt (5) Bolt insertion hole (6) Piping bolt (7) Piping flange (8) Butterfly valve (10) Recessed part (11) Closure plate

Claims (1)

A centering mechanism is provided in which a pipe bolt is brought into contact with the outer peripheral surface of the valve body at a predetermined interval, and the valve body and the pipe bolt are brought into contact with each other so that the center of the pipe is aligned with the center of the valve . In a wafer type valve, an arc-shaped recessed portion extending in the width direction is formed on the outer peripheral surface of a valve body that abuts on a pipe bolt, and a releasable closing plate bridged over a substantially central portion of the recessed portion. A wafer type wherein the outer surface of the closing plate is formed at least flush with the outer peripheral surface of the valve body, and the outer surface of the recessed portion is closed by the closing plate. Valve.

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