JPH11148565A - Ball valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball valve of a short inter-surface dimension, a compact construction, good sealing performance, and stable working torque, in which the number of component parts is decreased through single piece structuring of the body and the risk of fluid leakage is avoided through elimination of a split part. SOLUTION: This trunnion type ball valve is structured so that seal mechanisms 5, 6, 7 are supported by the body 1 movably along the flow passage and energized by a spring as advancing toward the ball 20, and is furnished at the passage end with flanges 2, 3, 4 to generate coupling with pipings, wherein the flanges 2, 3, 4 are formed in a single piece with the body 1, and an insert hole 19 for the ball 20 is formed in that surface of the body 1 besides the passage openings 1a, 1b, and 1c, and a cap 21 to seal and block the insert hole 19 is installed on the body 1, and a retracting means is furnished to make it possible for the sealing mechanisms 5, 6, 7 to retreat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a trunnion type ball valve.

[0002]

2. Description of the Related Art Generally, a ball valve of this type has a ball incorporated in a body, which is rotatably arranged at a fixed position by upper and lower stems, and a step formed on a body or a cap constituting a valve body and a ball surface. A seal mechanism is provided at the seal position between the valves.This seal mechanism is widely used as a valve with good sealing performance and operating torque, especially used for high-pressure fluid and large-diameter ball valves. ing.

In the above-mentioned seat mechanism, a seat retainer holding a seat at a leading end presses the seat against the ball surface by the action of a spring to exert sealing performance and operating performance. It rotates to open and close the fluid.

In the case of a two-way ball valve comprising a body and a cap, a sealing mechanism is mounted on the step of the body, and the ball is positioned and arranged in the body by upper and lower stems. Is connected to the body to form the valve body.

[0005] In the case of a three-way ball valve, each component of the valve body is separately manufactured into three or four parts by a split cap and a lid member having a body, a pipe joint, and a flow passage hole, and Then, the ball is positioned and arranged inside the body with the lid member with the upper and lower stems, and then a sealing mechanism is attached to the step formed on the inner peripheral end of each split cap. Individual split caps are respectively connected to the body to constitute a valve body. There are two types of connection between the body and the cap: a flange bolt type in which flange bolts are used for connection, and an insert screw-in type in which split caps are screwed into the body for connection.

[0006]

As described above, in the trunnion type ball valve, the sealing mechanism is resiliently arranged on the ball surface side by the action of a spring. In particular, in the case of a three-way ball valve, the valve body is used. Is divided into three parts or four parts, so that it has the following various problems.

First, since there are many divided components constituting the valve body, the cost is increased due to an increase in the number of components. In this case, a sealing member is required on each of the divided surfaces. There is not only a small risk of leakage, but also there are drawbacks such as an increased need for maintenance and inspection of the seal member.

Further, when the body and the split cap are connected by the flange bolt method, additional bolts are added to increase the number of parts, and when the body and the split cap are connected by the flange bolt method or the insert screwing method,
Both have drawbacks such as a decrease in the sealing performance of the connection division surface due to deformation of the connection portion due to piping stress.

In order to improve the drawbacks of the conventional splitting method, it is conceivable to integrate the valve body without splitting the valve body. However, in this case, it is necessary to mount the sealing mechanism and the components of the ball in the valve body. Becomes impossible.

The reason why the mounting is difficult is that, considering that the ball is not mounted in the valve body, the sealing mechanism is pressed and moved toward the center by the action of the spring. Becomes so narrow that it is virtually impossible to insert a ball. Further, even if the ball can be inserted forcibly, it is extremely difficult to rotate the ball and assemble it to a normal position, and therefore, it becomes impossible to assemble the ball at a normal position in the valve body.

The present invention has been developed to solve the above problems of the trunnion type ball valve. The object of the present invention is to reduce the number of parts by integrating the pipe joint and the body. To provide a ball valve which is compact, has a good sealability, and has a stable operating torque, while reducing the distance and eliminating the divisions to avoid the danger of fluid leakage, and shortening the face-to-face dimension. It is in.

[0012]

In order to achieve the above object, the present invention provides a trunnion type ball valve having a built-in seal mechanism urged toward the ball by a spring in a body. The pipe joint part is formed integrally with the body, an insertion port for inserting a ball on a surface other than the flow path opening of the body is formed, and the insertion port is covered with a cap via a cap, and the sealing mechanism is retracted by a retracting means. This is a ball valve provided so as to be able to retreat on the opposite side to the biasing direction.

Therefore, according to the present invention, since the pipe joint is formed integrally with the body, the number of parts is small and the number of sealing portions is small, so that there is no danger of fluid leakage, the device can be manufactured compactly, and the sealing mechanism can be manufactured. Since the retracting means for retracting is provided, even if the body is integrally molded, the sealing mechanism is retracted when the ball is inserted, the ball insertion port and the ball insertion space are expanded, and the body is rotated after the ball is inserted. After the ball is assembled in a normal position, the retracting means is released to urge the seal mechanism toward the ball surface.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment in which the ball valve of the present invention is applied to a trunnion type three-way ball valve will be described.

1 and 2, reference numeral 1 denotes a body for a three-way ball valve.
A flanges 2, 3 and 4 which are pipe joints for coupling with pipes are integrally formed with the pipes a, 1b and 1c. Furthermore,
Inner step 5 of flow path openings 1a, 1b, 1c of body 1
a, 6a and 7a include seal mechanisms 5, 6 and 7 described later.
Are installed.

The sealing mechanisms 5, 6 and 7 have the same structure. In FIGS. 4 and 5, a ring-shaped recess 9 is formed at the tip of the annular seat retainer 8 on the ball surface side.
An annular sheet 10 made of an elastic material such as resin or rubber is attached to the recess 9, and the sheet 10 is fixedly attached to the outer ring 11 via a bolt 12. Further, a spring 13 such as a disc spring, a plate spring, or a coil spring is mounted between the back side of the seat retainer 8 and the inner side of the body 1 to elastically urge the seat retainer 8 toward the ball 20. Reference numeral 14 denotes an O-ring inserted in a mounting portion 14a formed on the seat retainer 8 for sealing the contact surface between the seat retainer 8 and the body 1, and 14b denotes a seal ring mounted on the outer peripheral surface of the seat retainer 8. The sealing mechanisms 5, 6, and 7 are not limited to the above examples, and may be, for example, a mechanism that presses the metal sheet itself with a spring without providing a sheet retainer. Or a metal sheet such as a non-combustible sheet.

Reference numeral 15 denotes a retracting means which allows the seal mechanisms 5, 6 and 7 to retreat.
As shown in FIG. 3, a female screw portion 16 is formed at the rear end of the seat retainer 8, and a locking groove 17 is formed on the inner peripheral surface of the body 1 near the female screw portion 16. By locking the tapered surface of the distal end portion 18a of the temporary fixing bolt 18 screwed to the female thread portion 16 in the locking groove 17, the sealing mechanisms 5, 6, and 7 are formed by the horizontal component force of the bolt fastening force.
Overcomes the elastic force of the spring 13 to move the seat retainer 8 outward on the opposite side to the ball 20 to temporarily fix the seat retainer 8, and in this state, the seal mechanisms 5, 6, and 7 is retracted outward to form a ball insertion space. The length of the temporary fixing bolt 18 is sufficient and sufficient to lock the tip of the bolt in the locking groove 17.

The retracting means 15 is not limited to this example, and may be temporarily fixed to the locking groove 17 by a fixing pin instead of the temporary fixing bolt 18 or may be provided from outside the body 1. Seat retainer 8 using a jig or the like
Can be moved to be temporarily fixed.

In FIG. 2, reference numeral 19 denotes an insertion port for charging a ball 20 formed on a surface other than the flow path openings 1a, 1b, 1c of the body 1, and 21 denotes an insertion port 19 via an O-ring 22. The cap 21
Is fixed to the opening end 19a of the insertion opening 19 of the body 1 with a bolt 23. The same sealing mechanism 24 as the above-mentioned sealing mechanisms 5, 6, and 7 is mounted on the step portion 21a of the cap 21, and after the ball 20 is inserted into the body 1 and rotated to a normal position, Cap 21 with mechanism 24
To cover.

In FIG. 1, a T-shaped through hole 20a is formed in the ball 20, and mounting grooves 27, 28 for mounting the upper stem 25 and the lower stem 26 are provided in the upper and lower thick portions of the ball 20, respectively. Further, a ball rotation pin hole 29 is provided on the thick outer surface of the ball 20.

In FIG. 6, reference numeral 30 denotes an upper stem 25 which is attached to the shaft mounting portion 1b of the body 1 via a sealing member 31 to form a bolt 3.
The ground plate fixed at 2, 33 is the lower stem 26
Is an end plate fixed to the body 1 via a seal member 34.

Next, the operation of the above embodiment will be described. When the ball 20 is to be inserted from the insertion opening 19 of the body 1 as shown in FIG. 1, the temporary fixing bolt 18 is screwed into the female thread portion 16 of the seat retainer 8, and the distal end portion 18a of the temporary fixing bolt 18 3 is screwed into the V-shaped locking groove 17 of the body 1 until the tapered surface is inserted into the locking groove 17, and the bolt 18 is further tightened. As shown in FIG. The seat retainer 8 is a flange 2 for connecting pipes.
Since the seat 10 moves to the third and fourth sides, and the seat 10 attached to the tip of the seat retainer 8 also moves outward, the ball insertion space is expanded.

In this state, the ball 20 indicated by the chain line in FIG.
When the ball 20 is inserted into the ball insertion space at the position shown by the solid line in FIG.
After being rotated by 0 ° to the normal position, the upper stem 25 and the lower stem 26 are inserted into the upper and lower shaft mounting holes of the body 1 and mounted in the mounting grooves 27 and 28 of the ball 20, and assembled as shown in FIG. wear. In this case, since the ball 20 is inserted at a position where the width of the ball 20 is narrow, the ball is rotated by approximately 90 ° after the ball is loaded as described above. This is to reduce the dimension between the surfaces of the body 1 as much as possible to make the body itself compact. afterwards,
When the temporary fixing bolt 18 in the state shown in FIG. 4 is removed, the seat 10 incorporated in the seat retainer 8 moves toward the ball 20 by the resilience of the spring 13, and as shown in FIG. 20 comes into pressure contact with the surface.

As shown in FIG. 2, when the opening end 19a of the insertion port 19 of the body 1 is covered with a cap 21 having a sealing mechanism 24 via a bolt 23, the body 1 of the three-way ball valve is The ball 20 can be easily and reliably mounted in the body 1 even if it is integrally formed with the balls 2, 3, 4, and the seats 10 of the sealing mechanisms 5, 6, 7 and 24 are provided on the surface of the ball 20. Are brought into contact with each other and assembled as shown in FIG.

In the above example, a trunnion type three-way ball valve has been described. However, the present invention is not limited to this, and a retracting means for retracting a seat held by a seat retainer in the present invention is a trunnion type two-way ball valve. Also, the present invention can be applied to a four-way ball valve, and can be applied to temporarily retract or temporarily fix.

[0026]

As is apparent from the above, according to the present invention, since the body and the pipe joint for connecting the pipe are integrally formed, the number of components can be reduced, so that the apparatus can be manufactured compactly. Since this contributes to cost reduction and minimizes the number of connection portions connected to the body, there is no fluid leakage, and safety can be further improved by increasing rigidity due to the integrality of the body.

Further, since a retracting means for retreating the sealing mechanism is provided in the body, when inserting the ball from the insertion opening of the body, the ball is retracted to the outside by using the retracting means. Insert and rotate to assemble the ball, then release the sealing mechanism and release the sealing mechanism so that the sealing mechanism can contact the ball surface. This makes it possible to assemble the ball reliably and quickly, thereby providing an excellent ball valve having good sealing performance and stable operating torque.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a ball of a trunnion type ball valve according to the present invention is inserted into a body.

FIG. 2 is a cross-sectional view showing a state in which the ball of FIG. 1 is inserted, rotated, and a cap is attached.

FIG. 3 is an enlarged sectional view of a part showing an example of the retracting means of FIG. 1;

FIG. 4 is an enlarged sectional view showing a retracting means of the seal mechanism of FIG.

FIG. 5 is an enlarged sectional view in which a retracting unit of FIG. 4 is released.

FIG. 6 is a longitudinal sectional view of the ball valve of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body 1a, 1b, 1c Flow path opening part 2, 3, 4 Piping connection flange 5, 6, 7 Seal mechanism 10 Seat 13 Spring 15 Evacuation means 19 Insertion port 20 Ball 21 Cap

Claims (1)

[Claims] 1. A trunnion type ball valve having a built-in seal mechanism urged toward the ball side by a spring in a body, wherein a pipe joint portion is formed integrally with the body at a flow path end of the body, and a flow path opening of the body is formed. An insertion opening for inserting a ball on a surface other than the portion is formed, and the insertion opening is covered with a cap via a cap, and a sealing mechanism is provided by a retracting means so as to be retractable in a direction opposite to the biasing direction. Ball valve.