JPS6350539Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an air venting device such as a gate valve or a globe valve.

Prior Art A conventional internal threaded gate valve, for example, is constructed as shown in FIGS. In the same figure, 1 is a valve box,
Reference numeral 2 denotes a valve body that opens and closes a valve port 3 provided in the valve box 1. 4 is a bonnet installed on the upper part of the valve box via a bolt nut; 5 is a valve stem having a thread 6 formed on its outer circumference; and a piece 7 having a female thread 8 formed on its inner circumference in the male thread 6 of the valve stem. are screwed together and connected to the valve body 2 via the piece. The collar portion 9 of the valve stem 5 is held between the upper wall 4b of the bonnet 4 and a ring member 11 housed in a packing box 10 fixed on the bonnet 4, so that movement in the axial direction is restrained, and the upper end portion passes through the upper wall of the packing box 10, and a handle 12 is fixed by a nut 13 to the portion that protrudes to the outside.

The gate valves described above are subjected to water pressure tests before being shipped, but if there are any scratches or cracks on the valves, the valves may not be able to withstand the water pressure and may be damaged. At this time, the air in the pipe where the valve box 1 is installed and the air separated from the water during water supply accumulates in the upper part of the bonnet 4, and this becomes compressed air due to water pressure, so the damage is explosive. This has a serious effect on people and related equipment around the valve, or the air mixes with the water, resulting in cloudy drinking water that causes discomfort to users. Therefore, in order to prevent such difficulties,
As shown in FIG. 3, the curved side wall 4a of the bonnet 4
A through hole 15 was drilled in the through hole, and a screw plug 16 or a not-shown pot was attached to the through hole, and the air accumulated in the upper space of the bonnet 4 during the water pressure test was periodically vented to the outside. However, in the structure described above, since the through hole 15 is provided in the curved side wall 4a considerably below the upper wall 4b of the bonnet 4, the through hole 15
5 and the upper wall 4b of the bonnet 4, a large amount of air still remains, and the air cannot be completely vented, resulting in the problem that the above-mentioned problems still occur.

Setting of the Problem The technical problem of this invention is to prevent air from accumulating in the upper space of the bonnet 4.

Technical Means The technical means taken to solve the above technical problem is that one end of the valve stem is opened in the bonnet near the upper wall of the bonnet, and the other end is opened outside the bonnet. A communicating hole was drilled and a stopper was attached to the opening at the other end of the communicating hole.

Effects of the technical means The effects of the technical means are as follows. In other words, when the valve port is left open during a water pressure test and the inside of the valve box fills with water after the stopcock is removed, the air inside the valve box will move into the space above the bonnet. Air is drawn out from the opening at the other end of the bonnet through a communication hole opened at one end near the upper wall of the bonnet, thereby completely preventing air from accumulating in the upper space of the bonnet.

Unique effects This invention produces the following unique effects.

A communication hole for air vent is drilled at the top of the valve stem, so even if water reaches near the top wall of the bonnet during a water pressure test, the water will not leak out of the bonnet, and the stop valve Since the valve stem can be disposed near the member that rotates the valve stem, it is easy to attach and remove the valve stem, and the operability is extremely good.

Example Examples of this invention will be described below.

In FIGS. 4 and 5, reference numeral 20 indicates a communication hole bored in the upper part of the valve stem 5, and this communication hole 20 is connected to the bonnet 4.
A horizontal hole 20a opened near the top wall of the bonnet inside.
and a vertical hole 20b communicating with the horizontal hole 20a, and a screw plug 21 is attached to the opening of the vertical hole 20b. In place of the screw plug 21, a plug or the like may be attached as in the conventional case. In addition, since other parts are the same as those of the prior art, the same reference numerals are given to the same parts, and the description thereof will be omitted.

Next, the operation of the above embodiment will be explained.

Normally, a valve is opened and closed by operating the handle 12 and rotating the valve stem 5. When the valve stem 5 is rotated, the valve stem itself does not move in the axial direction, but the male thread 6 and the female thread 8, the valve body 2 moves up and down in the axial direction of the valve stem 5 via the piece 7, thereby opening or closing the valve port 3. When venting air during a water pressure test, etc., by opening the valve port 3 and removing the screw plug 21, the inside of the valve box 1 will be filled with water and the air inside the valve box will flow into the upper space of the bonnet 4. The air enters the horizontal hole 20a of the valve stem 5, and is extracted from there through the vertical hole 20b to the outside of the bonnet, so that air does not accumulate in the upper space of the bonnet 4. After the air has been vented, the screw plug 21 is attached again.

If a small air valve is attached to the opening of the vertical hole 20b instead of the screw plug 21, the air accumulated in the valve box 1 can be separated from the water being fed and removed. Further, in the above embodiment, the handle 12 is fixed to the valve stem 5, but as shown in FIG. It goes without saying that 23 can also be applied to a gate valve operated by a dedicated T-shaped handle (not shown). To vent air in this case, loosen the bolt 24, remove the cap 23, and then remove the screw plug 21.

[Brief explanation of the drawing]

Fig. 1 is a partially longitudinal front view of the conventional device, Fig. 2 is a partially longitudinal side view of the same as above, Fig. 3 is an enlarged longitudinal sectional side view of the main part of the same as above, and Fig. 4 is a third embodiment of the invention.
5 is an enlarged front view of the upper part of the valve stem, and FIG. 6 is an enlarged front view of the main part showing another embodiment. 1...Valve box, 2...Valve body, 3...Valve port, 4...
Bonnet, 5...Valve stem, 20...Communication hole, 21
...screw plug.

Claims (1)

[Scope of utility model registration request] A bonnet is provided at the upper part of the valve box, and a valve body is screwed and connected to the lower end of a valve stem that is arranged vertically passing through the bonnet, and the valve body moves up and down as the valve stem rotates. In an internally threaded valve that opens and closes a valve port provided in a valve box, a communication hole is provided in the upper part of the valve stem, with one end opening in the bonnet near the upper wall of the bonnet and the other end opening outside the bonnet. An air venting device such as a gate valve, characterized in that a stopper is attached to the opening at the other end of the communication hole.