JPH0351586A - Reinforcing seat for ball valve - Google Patents

Abstract

PURPOSE:To previously prevent the early breakage of a seat by forming an annular groove on the outer periphery of the seat of a valve and fitting a split type reinforcing ring made of metal in the annular groove and fitting the outer peripheral surface of the ring onto the inner peripheral surface of the seat of a valve box in static manners. CONSTITUTION:When a valve body 30 contacts a sealing surface on one side of a seat 20 and is in separation from a sealing surface on the opposite side, even if the fluid pressure in a valve box flow passage 13 tends to float up the seat 32 at the part from the back surface of the seat, as shown by the arrow B, the floating-up of the seat 20 at the part is prevented, since the outer peripheral surface of a reinforcing ring 26 is fitted through the static fitting onto the inner peripheral surface of the seat 16 of the valve box 10. Therefore, the floating-up of the seat 20 is prevented by the reinforcing ring 26, and the inner and outer edges of the part of the seat 20 separated from the valve body are kicked up by an annular part 34, and the breakage in the early period is prevented.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to reinforcing the seat of a ball valve.

[Prior Art] As shown in FIG. 10, a ball valve consists of a Got box 10, a sheet 20 made of fluororesin fitted to the inner end surface of a valve box flow path 12, and a sheet 20 in contact with the sheet. When the valve body 30 is rotated in one direction, the valve body flow path 32 passing through the valve body 30 communicates with the valve body flow path 12 to open the valve, and the valve body 30 is rotated in the opposite direction. When rotated, the annular portion 34 of the valve body 30 blocks the valve box flow path 12 and closes the valve. While rotating the valve body 30 in the direction of arrow A, one side of the seat 20 in the diametrical direction contacts the valve body 30, but the opposite side separates from the valve body 30.

Therefore, if the rigidity of the seat 20 is low, the opposite side of the seat 20 will be lifted up as shown by the chain line due to the fluid pressure shown by the arrow B in the valve box flow path 12. As a result, the valve body 3 has rotated.
The raised inner edge of the seat 20 is kicked up by the annular portion 34 of 0.

Although not shown, when the valve body 30 rotates in the opposite direction after closing the valve, the outer edge of the seat 20 that has floated up is kicked up by the annular portion 34' on the opposite side of the -JR body 30.

In this manner, each time the valve is opened or closed, a portion of the inner and outer edges of the seat 20 are struck by the valve body 30 and are rapidly damaged. In order to prevent this damage, reinforcing sheets with increased rigidity are used.
It is known that a metal retainer or a metal ring is fitted on the outside, or a metal ring is integrally formed inside the seat.

[Problems to be solved by the invention] A metal retainer or a metal ring fitted externally requires high production costs and assembly costs for attaching the metal retainer or ring, and a metal ring integrally molded inside the metal retainer or ring is expensive. Since the molding cost is significantly high, there is a problem that the ball valve is relatively expensive.

The present invention has been made to solve this problem, and its purpose is to increase the rigidity of a ball valve seat at a relatively low cost.

[A Thousand Steps to Solve the Problem] In order to achieve the above object, the R step adopted by Moku Invention is to provide an annular groove on the outer periphery of the seat of the ball valve, and a metal split-type reinforcing ring in the annular groove. The outer peripheral surface of the split ring is statically fitted into the inner peripheral surface of the seat seat of the valve box.

[Operation] When the valve body moves when the valve is opened or closed, one side of the seal 1 in the diametrical direction comes into contact with the valve body, and the opposite side separates from the valve body. At this time, the fluid pressure acting from the back of the seat tries to lift the part of the seat away from the valve body, but since the outer circumferential surface of the reinforcing ring fits into the inner circumferential surface of the seat seat with a tight fit,
The reinforcing ring prevents the sheet from floating. In this way, the portion of the sea 1 separated from the valve body will not float up, so there is no risk that the inner and outer edges of that portion will be kicked by the valve body and be damaged quickly.

[Example] The reinforcing sheet for a ball valve of the present invention will be explained based on an example shown in the drawings.

As shown in FIG. 1, the valve box 10 of the ball valve consists of left and right half-holes, and the center of the left and right half-holes is connected to a cylindrical goose ``box flow path 1''.
2 penetrates. An annular seat 1 and seat 16 are provided on the left and right inner end surfaces of the valve box flow path 12, and an annular seat 20 made of fluororesin is fitted into the seat 1 and seat 16. The inner end surfaces of the left and right seats 20 are formed into sealing surfaces, and the spherical valve body 30 is in contact with the sealing surfaces. A square groove 36 is provided in the annular portion 34 of the valve body 30, and a dihedral shaft 38 of the handle 37 fits into the square groove. Two surface directions of the square shaft 38 are orthogonal to the axes of the valve box flow path 12 and the valve body flow path 32.

As shown in FIGS. 2 and 3, an annular groove 25 is provided on the outer periphery of the seat 20, and a metal reinforcing ring 26 in the form of a semicircular split ring is fitted into the annular groove. When the reinforcing ring 26 fits into the annular groove 25, the reinforcing ring 2
The outer circumferential surface of G is statically fitted to the inner circumferential surface of the seat seat 18 shown in FIG. The sheet 20 is made by cutting a tube made of fluororesin resin and forming an outer circumferential groove 25 by machining, or by machining the outer circumferential groove 25 on the outer periphery of the molded sheet 1. The reinforcing ring 26 is an inexpensive piece obtained by cutting a metal tube, has a rectangular cross section, and has an axial radius equal to or greater than its radial width. The abutment part of the sleeve reinforcing ring 26 does not have to be limited to the shape shown in FIG. 4; the abutment 1-1 part 27 of the reinforcing ring 26 may be diagonally crossed as shown in FIG. It may be stepped like this. In addition, the split ring type does not need to be limited to a semicircular shape;
As shown in the figure and FIG. 8, the reinforcing ring 26
It may be a circular split ring type with a cutout 28 on the opposite side of the ring 7 or a circular split ring type without a cutout.

As shown in FIG. 9, when the valve body 30 contacts the seal surface 24 on one side of the seal 20 but separates from the seal surface 24 on the opposite side, the valve body 30 is exposed from the back surface of the seat 20 in the valve body flow path 12. Even if the fluid pressure attempts to lift the seat 20 in that area as indicated by arrow B, the outer circumferential surface of the reinforcing ring 26 is statically fitted to the inner circumferential surface of the seat seat l6 of the valve box 10. Therefore, the lifting of the seat 20 in that area is prevented. In this manner, the reinforcing ring 26 prevents the seat 20 from floating up, so there is no risk that the inner and outer edges of the portion of the seat 20 away from the valve body will be kicked up by the annular portion 34 and be damaged early.

[Effects of the Invention] As described above, the present invention involves fitting a metal split ring type reinforcing ring into an annular groove provided on the outer periphery of a fluororesin sheet, and extending the outer periphery of the reinforcing ring to the inner periphery of the seat seat of the valve box. Since it is statically fitted to the surface and prevents the sheet from floating, it is possible to prevent early damage to the sheet. Compared to a metal ring formed in one piece, the manufacturing cost is significantly lower, which is a special effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a pol valve equipped with a seat according to an embodiment of the present invention; FIGS. 2 and 3 are a front view and a side view showing the upper half of the seat in FIG. 1; The figure is a perspective view of the reinforcing ring in Figure 1, Figures 5 to 8 are views corresponding to Figure 4 of different embodiments, and Figure 9 is when the valve body of the ball valve in Figure i is rotated. FIG. 10 is a view corresponding to FIG. 9 of a conventional valve with a seat. In the figure, reference numeral 10 indicates a valve box, 16 a seat seat, 20 a seat, 25 an annular groove, and 26 a reinforcing ring.

Claims (1)

[Claims] 1) A valve box (10), a spherical valve body (30) rotatable within the valve box, and a valve box flow path (1) that passes through the valve box.
2), a valve body channel (32) passing through the valve body (30) in a direction perpendicular to its rotation axis, and a seat seat (16) provided on the inner end surface of the valve body channel of the valve body. and an annular seat (20) fitted into the seat seat and in contact with the valve body.
In the ball valve, an annular groove (25) is provided on the outer periphery of the seat (20), a metal split-type reinforcing ring (26) is fitted into the annular groove, and the outer circumferential surface of the reinforcing ring is A reinforcing sheet for a ball valve, characterized in that it is statically fitted to the inner peripheral surface of the seat seat (18).