JPS6326615Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to buried ball valves used in city gas piping, which require emergency shutoff performance, durability, and operability. This invention relates to a ball valve for burial.

[Prior art]

Conventionally, ball valves for buried city gas piping have often been installed in large dedicated pits installed underground. However, in large cities,
Due to the recent rise in land prices and the overcrowding of underground structures, the use of large dedicated pits has become less common. Instead, as shown in Figure 5, the ball valve was piped directly into the ground, and the outer surface was treated with some kind of anti-corrosion treatment to protect the rotating part of the ball valve's gland all the way to the ground surface to prevent it from interfering with the surrounding soil. A tube 23 is provided, and a small pit 16 and a lid 17 are provided near the ground surface, and the ball valve can be opened and closed by inserting a special tool from the ground, engaging it with the protrusion 12 on the ball valve head, and rotating these. This led to the use of ball valves to open and close them.

Such ball valves generally include cap-type ball valves in which a cap member is fitted onto the top of a valve box. The sealing structure of the cap portion of this cap-type ball valve is usually a double sealing structure consisting of a packing in the valve box gland portion and an O-ring provided on the inner peripheral surface of the cap. That is, as shown in Fig. 2, the seal structure of the cap part is as follows.
It consists of a first seal consisting of a gland packing 9 and a second seal consisting of an O-ring 15 interposed between the outer circumferential surface of the head flange 2 of the valve box 1 and the inner circumferential surface of the cap 3. . The cap 3 forms the second seal, and the tip of the valve stem 4 is engaged with the groove corner 6 provided at the center of the lower surface, and the end of the valve stem 4 is fitted tightly to prevent the cap 3 from falling off. Provide a screw 7, screw it together with a bolt 8, and attach the cap 3.
and the valve stem 4 is fixed. Therefore, when the cap 3 is rotated, a ball (not shown) is rotated via the valve stem 4, thereby opening and closing the ball valve.
Further, the rotation of the ball through 90 degrees is restricted by the contact between the packing retaining bolt 18 and a wall integrally formed in the space inside the cap. (Not shown.) [Problem to be solved by the invention] However, in the conventional cap structure described above, the cap 3 and the valve stem 4 are fixed with bolts 8, and when opening and closing the ball valve, there is no need to pass through the cap. The force applied to the valve stem 4 is not only rotational force, but also bending and compressive force, which causes the valve stem 4 to grind, reducing the performance of the seal 9, causing fluid leakage, and causing double damage. There is a problem that the seal is destroyed.

The purpose of the present invention is to solve the above problems and provide a buried ball valve having a cap structure that prevents the cap from falling off and restricts opening and closing at 90 degrees.

[Means for solving problems]

The present invention provides a ball valve for burial, in which a packing box is formed at the head of the valve box, a cylindrical part is formed that protrudes from the packing box, and a handle cap is fitted into the cylindrical part and is rotatable. , the upper end of the valve stem is fitted into a concave groove formed in the center of the lower surface of the handle cap, and an opening groove for regulating opening and closing is provided on the side surface of the cylindrical portion of the valve box, the opening groove having a length in the circumferential direction; A set screw member that engages with the opening groove is provided on the side surface of the handle cap.

[Effect]

According to the present invention, when the handle cap 3 is rotated, the ball rotates via the valve stem 4, and the handle cap falling-off prevention member is provided separately from the valve stem by a set screw member in the direction of rotation of the cap. Therefore, unreasonable forces such as bending and compressive forces are not applied to the valve stem, and the sealing performance of the packing 9 is maintained. Furthermore, the set screw member engages with the opening groove 13 and functions as a stopper for regulating opening and closing.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view of the buried ball valve according to this embodiment, FIG. 3 is a perspective view of the handle cap, and FIG. 4 is a perspective view of the protruding cylindrical portion of the head of the valve box. In FIG. 1, a valve box 1 consists of left and right valve boxes, which are combined into one valve box by bolts. Inside the valve box, there is a ball with a through hole,
A seat ring is placed in contact with the ball at symmetrical positions on both sides of the ball. By rotating the valve stem 4 engaged with the upper part of this ball by 90 degrees,
Rotate the ball 90 degrees to pass or block fluid.
The ball valve of FIG. 1 is in an open state, allowing fluid to pass therethrough, and is closed by rotating the ball 90 degrees from this state. There is a packing box on the head of the valve box, and packing 9 is attached. Patsukin 9 is
It is tightened by screwing the packing retaining screw 10 into the head of the valve box via the disc spring 11. By tightening this gasket 9, a first seal that seals the liquid is implemented. The above is the general basic structure of a ball valve, but in addition to this basic structure, the buried ball valve of this example has the following features:
The handle cap structure has been improved to make it particularly suitable for buried use. This point will be explained below.

A cylindrical portion 2 is formed to protrude from the packing box of the head of the valve box 1, and an O-ring 15 is interposed on the outer circumferential surface of this cylindrical portion, and the inner circumferential surface 12 of the handle cap is fitted to perform a second seal. At the same time, the square part 6 of the concave groove formed at the center of the lower surface of the handle cap 3 is engaged with the square part 5 at the end of the valve stem. The signal can be transmitted to the ball via the valve stem to open and close the valve.

The side surface of the cylindrical portion 2 is provided with an opening groove 13 having a length in the circumferential direction and for regulating opening and closing, as shown in FIG. In this case, the length of the opening groove is the length for 90° rotation plus a slight margin, and can be formed with relatively high precision by machining. A set screw member 14 is provided on the handle cap so that it fits into the opening groove 13 when the handle cap 3 is fitted (see FIG. 3). In the above, when fitting and assembling the handle cap 3 to the cylindrical part 2, the length and opening position of the opening groove 13 are made to match the positional relationship of the through hole of the ball, and the two are fitted together. It is fixed with a set screw 14. In this case, the set screw member 14 functions to prevent the handle cap from falling off, and also serves as a stopper for regulating opening and closing.

Finally, the O-ring 1 provided at the bottom of the protruding cylindrical part
5 also prevents groundwater and other earth and sand from entering the inside of the valve. If a synthetic resin layer is formed on this rotating portion, an electrically insulating type can be easily manufactured. Although not specifically mentioned in this embodiment, since the present invention is a buried valve, the outer surfaces of the valve box, handle cap, etc. must be treated with anticorrosive treatment such as anticorrosive tape or anticorrosive coating. Furthermore, the present invention can be applied not only to ball valves but also to cock valves, butterfly valves, etc. that are regulated to open and close at 90° or 180°.

[Effect of idea]

The buried ball valve according to the present invention integrates the valve opening/closing regulation function and the handle cap falling prevention function at the fitting part between the protruding cylindrical part of the valve box and the handle cap, so the opening groove for opening/closing regulation is machined. Since it can be formed by
In addition, the valve stem is not subjected to bending or compressive force, which has the effect of maintaining sealing performance for a long time.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a buried ball valve according to the present invention, FIG. 2 is a partial cross-sectional view showing the handle cap structure of a conventional buried ball valve, and FIG.
FIG. 4 is a perspective view of the handle cap according to the present invention, FIG. 4 is a perspective view showing the protruding cylindrical portion of the upper part of the valve box according to the present invention, and FIG. 5 is a diagram showing how the buried ball valve is installed. 1...Valve box, 3...Handle cap, 4...
Valve stem, 5... Valve stem square part, 6... Handle cap concave groove, 10... Packing retainer screw, 11...
Belleville spring, 13...Opening groove, 14...Set screw member, 15...O ring.

Claims (1)

[Scope of utility model registration request] An buried ball valve that has a ball having a through hole and a seal member in a valve box, and opens and closes by rotating the ball 90 degrees through a valve stem,
A packing box is formed at the head of the valve box, and a cylindrical part is formed that protrudes from the packing box, and a handle cap that is rotatable by fitting into the cylindrical part is provided, and a handle cap is formed at the center of the lower surface of the handle cap. The upper end of the valve stem is fitted into the concave groove, and an opening groove for regulating opening and closing is provided on the side surface of the cylindrical portion of the valve body and has a length in the circumferential direction. A buried ball valve characterized by being provided with a set screw member that engages with an opening groove.