JPS6158706B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Industrial Application Field This invention relates to a top entry type ball valve.

(2) Prior art In top entry type ball valves, the seat receiving surfaces around the valve holes on the low pressure side and high pressure side in the valve chamber are tapered to improve the adhesion between the ball valve body and the seat ring. It has been conventionally practiced to form However, when the seat receiving surface is formed into a tapered surface, the optimal range of the insertion depth of the ball valve element inserted between the seat rings is narrow (i.e., if it is too deep, the torque will be excessive, and conversely, if it is too shallow, the seal will be poor). Therefore, there was a problem in that it was difficult to maintain the best operability and sealing performance. Further, there were also problems such as it was difficult to process the tapered surface and sufficient surface accuracy could not be obtained.

On the other hand, there is also a top entry type ball valve in which the opposing seat receiving surfaces are formed parallel to each other, but in order to make the seat ring come into close contact with the ball valve body, the high pressure side seat receiving surface has a combination of a seat ring, a disc spring, and a seat ring holder. A seat ring assembly is provided, the seat ring holder is screwed into the high pressure side valve hole, and the seat ring holder is rotated from outside the valve hole to push it toward the ball valve body or to move it backward. be.

However, with such a configuration, the structure is complicated because a thread must be formed in the valve body, and powder, etc., which is the object to be transported, may stick to the threaded part, making it difficult to disassemble. There's a problem.

(3) Problems to be Solved by the Invention In view of the above-mentioned prior art, the present invention provides a top-entry ball valve in which opposing seat receiving surfaces are formed parallel to each other, in which the high-pressure side seat receiving surface and the ball valve body are connected to each other. A problem to be solved is to easily assemble a seat ring assembly consisting of a seat ring, a disc spring, and a seat ring interposed inside a valve body without performing any special processing on the valve body. That is.

(4) Means for solving the problems In order to solve the above problems, this invention
Seat ring assembly 1 installed on the high pressure side
The peripheral wall 1 is attached to the seat ring holder 15 that constitutes the seat ring holder 2.
6, and a clamp jig engagement groove 17 is formed on the outer peripheral surface of the peripheral wall 16.
The seat ring assembly 12 is assembled by storing the seat ring 13 in the inner recess 16' with the disk spring 14 interposed therebetween, and when the seat ring assembly 12 is assembled in the valve chamber 2, the seat ring 13 and the seat are assembled. Ring holder 1
5, a gap Δl is provided between the disc spring 14 to compress the seat ring holder 15 and the seat ring 13, and the upper half of the peripheral wall 16 of the seat ring holder 15 to open the valve chamber 2. The structure is such that the portion 4 is exposed.

(5) Function The seat ring holder 15 is assembled with the disc spring 14 and the seat ring 13 in its recess 16', and then the seat ring holder 15 is assembled with a separately prepared clamping jig 18.
is engaged with the engagement groove 17 of the seat ring holder 15 and the seat ring 13, and tightened in a direction that compresses the disc spring 14, thereby reducing the gap Δl between the seat ring holder 15 and the seat ring 13. , or substantially zero, and the valve chamber 2 together with the ball valve body 3 and the low pressure side seat ring 11
Insertion into the valve chamber 2 or extraction from the valve chamber 2 is performed.

When inserted into the valve chamber 2, when the clamp jig 18 is removed after positioning, the seat ring 13 is brought into close contact with the ball valve body 3 with a required pressing force due to the elasticity of the disc spring 14.

(6) Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings.

As shown in FIG. 1, the ball valve of the present invention is of a so-called top entry type in which the upper part of the valve chamber 2 of the valve body 1 is opened and the ball valve body 3 can be taken in and out through the opening 4. , seat receiving surfaces 7 and 8 formed around the low-pressure side valve hole 5 and around the high-pressure side valve hole 6, respectively, inside the valve chamber 2 are opposed in parallel.
Semicircular arc-shaped step portions 9 and 10 are formed substantially along the outer periphery of the lower half of each of these seat receiving surfaces 7 and 8, so as to prevent the seat ring 11 and seat ring assembly 12 described below from swaying. It's summery. The stepped portions 9 and 10 are formed such that their upper end surfaces are located a minute distance Δx below the center points of the valve holes 5 and 6 (see FIG. 2).

A seat ring 11 supported by the stepped portion 9 is interposed between the low pressure side seat receiving surface 7 and the ball valve body 3, and between the high pressure side seat receiving surface 8 and the ball valve body 3. is also the step portion 10 mentioned above.
A seat ring assembly 12 supported by the seat ring assembly 12 is interposed. This seat ring assembly 1
2 is a combination of a seat ring 13, a disc spring 14, and a seat ring holder 15. The seat ring holder 15 has a peripheral wall 16 protruding inward from the valve chamber 2 formed on the outer peripheral edge of an annular portion having a hole that matches the valve hole 6.
A disc spring 14 is installed in the concave shape 16' inside the peripheral wall 16.
and seat ring 13 are incorporated. Belleville spring 1
4 is fitted into the annular stepped portion 13' of the seat ring 13 on the holder 15 side, and is pressed between the seat ring 13 and the holder 15. In the state shown in FIG. 1 in which the seat ring assembly 12 is assembled into the valve chamber 2 and the disc spring 14 exerts its elasticity, there is a slight gap Δl between the seat ring 13 and its holder 15. . Furthermore, an engagement groove 17 is formed on the outer periphery of the peripheral wall 16 of the seat ring holder 15.

Since the seat ring assembly 12 has a built-in disc spring 14, its overall thickness is large when the disc spring 14 is in an uncompressed state, and it cannot be assembled into the valve chamber 2 as it is. Can not. Furthermore, when removing the valve chamber 2, it is difficult to remove the valve chamber 2 because of the large frictional force caused by the elasticity of the disc spring 14.

Therefore, when inserting and removing the seat ring assembly 12, it is convenient to use a clamp jig 18 as shown in FIGS. 4 to 6, for example. Clamp jig 18 in this case
consists of two front and rear clamping pieces 20 and 21 having a semicircular recess 19 (see FIG. 6), and the inner periphery of the recess 19 of one clamping piece 21 is connected to the engagement groove 17 of the peripheral wall 16 of the holder 15. and the other clamping piece 20
The inner circumferential edge of the recess 19 is engaged with the seat ring 13. Projecting pieces 22 and 23 are formed on the upper part of each clamping piece 20 and 21, and each protruding piece 2
Make the inner surfaces of 2 and 23 slightly protrude inward, abut the protruding surfaces against each other, and then tighten the bolt 2 at two points at the same height below the abutted parts.
4 and 25 to tighten the two clamping pieces 20 and 21.

Now, when the seat ring assembly 12 is engaged with both of the clamping pieces 20 and 21 as shown in FIG. piece 22,
Using the lower end of the inner surface of the spring 23 as a fulcrum, the portions below the fulcrum approach each other to compress the disc spring 14. As a result, the seat ring assembly 12 has a reduced overall thickness. Therefore, the ball valve body 3, the low-pressure side seat ring 11, and the seat ring assembly 12 can be inserted into the valve chamber 2 at the same time, or conversely, can be extracted from the valve chamber 2.

FIG. 1 shows the seat ring assembly 12 inserted into the valve chamber 2 according to the above procedure, and the bolt 2
4 and 25 to remove the clamp jig 18, and in this state, the peripheral wall 16 of the seat ring assembly 12 and the upper half of the seat ring 13 are exposed to the opening 4 to the valve chamber 2 and its upper part. , the clamp jig 18 can be inserted and engaged therewith.

Note that, as shown in FIG. 6, both sides of the clamp jig 18 protrude slightly laterally from both sides of the seat assembly 12, and these portions are connected to the valve chamber 2.
It is received in a space formed above the upper end surfaces of the stepped portions 9 and 10 (see FIG. 2).

In addition, 26 in Fig. 1 is the bonnet,
Reference numeral 27 denotes an operation section, which is conventionally known.

In the above-mentioned embodiment, the stepped portions 9 and 10 are provided in the valve chamber 2, and these are used to position the seat ring 11 and the seat ring assembly 12 and to prevent them from steadying in the direction of rotation of the valve body. Although providing the stepped portions 9 and 10 has certain merits, these stepped portions 9 and 10 are not necessarily a necessary configuration to achieve the object of the present invention.

(7) Effects Since the ball valve of the present invention is as described above, the seat ring assembly consisting of the combination of the seat ring, disc spring, and seat ring holder can be compressed in the thickness direction using an appropriate clamping jig. . As a result, in a top-entry ball valve with parallel seat receiving surfaces, the simple structure allows the ball valve body and the like to be easily assembled together with the seat ring assembly, and also to be easily disassembled.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the embodiment, Fig. 2 is a vertical sectional side view of the valve body, Fig. 3 is a partially omitted cross-sectional plan view of the valve body, and Figs. 4 and 5 are parts of the clamping jig in use. FIG. 6 is a partially omitted front view of the same as above. 1... Valve body, 2... Valve chamber, 3... Ball valve body, 4... Opening part, 5, 6... Valve hole, 7, 8
... Seat receiving surface, 9, 10 ... Step portion, 11 ... Seat ring, 12 ... Seat ring assembly,
13...Seat ring, 14...Disc spring, 15...
...Seat ring holder, 16...Peripheral wall, 17...
Engagement groove, 18...clamp jig.

Claims (1)

[Claims] 1 The upper part of the valve chamber 2 is opened, and the seat receiving surfaces 7 and 8 around the low pressure side and high pressure side valve holes 5 and 6 in the valve chamber 2 are formed in parallel, and the low pressure side seat receiving surface 7 and the ball valve body are formed in parallel. 3
A seat ring 13 is interposed between the high pressure side seat receiving surface 8 and the ball valve body 3, with a seat ring 11 interposed therebetween;
In a top-entry ball valve that includes a seat ring assembly 12 consisting of a disc spring 14 and a seat ring holder 15, a peripheral wall 16 is formed on the seat ring holder 15, and a clamp jig engagement groove is formed on the outer peripheral surface of the peripheral wall 16. 17, and assemble the seat ring assembly 12 by storing the seat ring 13 in the recess 16' inside the peripheral wall 16 with the disc spring 14 interposed therebetween;
When the seat ring assembly 12 is assembled into the valve chamber 2, the disc spring 14 is compressed between the seat ring 13 and the seat ring holder 15.
A top entry type ball valve characterized in that a gap Δl is provided to allow the two to approach each other, and the upper half of the peripheral wall 16 of the seat ring holder 15 is exposed to the opening 4 of the valve chamber 2.