JPH0567836B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a device for sealing fluid leakage from the valve stem in various valves, valves, etc., and is particularly applicable to water supply systems buried underground. A leak-proof device for the valve used.

(Prior Art) Conventionally, as a means of sealing leakage from the stem of this type of valve, for example, as disclosed in Utility Model Publication No. 40-31181, ring grooves for reducing pressure are provided at appropriate intervals in gland packing housed in a packing box. In some cases, a packing plate is installed on the bottom and top of the packing box to prevent leakage from occurring during the valve stem. Insert the two split collars that serve as a stopper overlapping each other, then add a washer-shaped stopper to this, insert this stopper into the packing presser bolt set in the packing box, and hold the nut with the nut. There are known means to prevent leakage of the valve stem through gland packing by pressurizing a split collar, an O-ring, and a packing holder.

(Problems to be Solved by the Invention) Conventionally, in this type of valve, not only the above-mentioned conventional example but also leakage from the valve stem due to gland packing of a relatively small valve installed in a branch pipe, for example. In terms of water supply gate valves, it is necessary to first close the gate valve at the relatively large main valve before the branch, and then perform leakage prevention work. There is a drawback that the water flow through the gate valves of the branch pipes is stopped.
In particular, gate valves with many main valves in underground bits (usually 2m cubic concrete boxes), and valves for small gate valves that are installed in branch pipes downstream of this valve and are buried underground. Kiyo (usually 200
It has a tubular shape with a diameter of about mm and its surface is exposed to the ground)
A small gate valve installed in a valve has a key cap attached to the upper end of the valve stem, which fits into a rotating handle to rotate the valve stem, and is fixed with a dowel pin. Therefore, the general work procedure for repairing water leaks in the gland, especially in the current state of gate valves in valve cages, is as follows: (1) To ensure that pressure water does not come out during work from the gate valve that requires repair and does not interfere with the work. , close the main valve installed in the upstream pipe of the gate valve to cut off the water supply.

(b) Excavate from the road surface and remove the valve cover to expose the upper part of the gate valve.

C. Remove the dowel pin attached to the key cap of the gate valve, remove the key cap, remove the gland packing holder, bolt nut, and packing holder, and replace the gland packing with a new one.

D. Perform the above work in reverse to restore the installation state to the state before the start of work and complete.

Therefore, the problems are as follows: a. If the road surface is paved, a great deal of wasted cost and time is required for digging and repair work.

b The dowel pin that holds the key cap in place cannot be removed easily and requires a lot of effort.

c Once the gland packing has been replaced, it may need to be replaced many times due to age or operation.

d The construction period will be interrupted and the water will cause great inconvenience to nearby residents.

There are other problems.

(Means for solving the problem) For example, an inverted funnel-shaped adapter is placed over the key cap part of the valve stem head of a gate valve that needs to be prevented from leaking, and attached to it, and manufactured to fit the valve stem part. While expanding the ring packing, which has sufficient elasticity, pass through the key cap part and fit it into the valve stem part. Next, attach the ring packing to the ring packing presser, which is made in one piece and can be split into two or opened and closed. For example, the ring packing is held by the ring packing presser using a jig such as a magic hand, and the ring packing is placed on the valve stem above the ring packing presser.

Furthermore, in the same manner as in the ring packing, a pressurizing body made to be stretchable and fit to the valve stem is attached to the exposed part of the valve stem between the lower surface of the key cap and the upper surface of the ring packing presser in the same manner as in the ring packing. Attach the crimped body with a jig such as a magic hand so as to cover the outer periphery of the crimped body, and tighten the crimped body with a special screwdriver (preferably one with a long handle and an adjustable cutting edge rotation direction), etc. By causing the pressurizing body to deform in the axial direction, the ring packing is strongly pressurized to the valve stem and the upper part of the ring packing presser through the ring packing presser to prevent leakage water. It can be stopped.

That is, unlike the conventional general water leakage prevention method, the structure and procedure described above allows water leaking from the gate valve to flow from the ground through the upper opening of the gate valve, while remaining buried underground, to the water supply of the entire nearby area. Leakage around the valve stem can be semi-permanently sealed without water outage, without digging up the road surface, without removing the key cap, and without replacing the gland packing. In the case of underground pits, the above-mentioned work can be carried out even more easily by a construction worker who enters the pit without having to perform above-ground work.

(Example) Next, the gate valves for each door of the underground sewer pipe shown in the drawings as an example of the present invention will be described in detail.

In the gate valve for a doorway in a water supply system, a in FIG. 2 is a water pipe, and a gate valve c is connected to the water pipe a inside the valve b described above.

The gate valve c consists of a valve box 1, a packing box 2, a packing presser foot 3, etc., and the valve stem 4 connected to the valve body in the valve box 1 (see also Fig. 1 below) is the packing box 2.
A large-diameter key cap 5 that fits on the valve stem 4 is attached to the upper end of the key cap by driving in a dowel pin 6, and a removable rotary handle (generally kept by the worker) is attached to the upper end of the key cap 5, which has a large diameter and is fitted onto the valve stem 4. It has a prismatic portion 5' that engages with a rotary handle that is operated by opening the above-ground cover of the valve canister b and inserting a rotary handle thereinto to operate the valve.

A gland packing 7 is packed in the packing box 2, and a packing presser 3 (in the embodiment, via a bushing 3') is pressurized with a bolt 8 and a nut 9, and the valve rod 4 and packing presser 3 are pressed together.
This prevents water leakage between the Some water leakage in this area is unavoidable due to processing or over time, so tighten the packing regularly or during water outages, tighten the nut 9, or replace the packing. However, if water leaks outside of the above-mentioned periods, water will enter into valve b and corrode gate valve c, or since the valve is directly underground, nearby soil may flow out, so take measures to stop the leak as soon as possible. At that time, as mentioned above, the water supply to the main valve is stopped, and the water supply to each household that is supplied from the main valve is stopped, which has a large negative impact.

The present invention utilizes the exposed portion of the valve stem 4 between the packing presser foot 3 and the key cap 5 to prevent water leakage from the packing 7 at this portion.
First, fit the ring packing 10 onto the valve stem 4.
For this purpose, the ring packing 10 has an appropriate elasticity to allow the key cap 5 (which has been hammered in so strongly that the lock pin 6 cannot be removed and is rusted due to moisture and water leakage underground) whose diameter has expanded from the valve stem 4 to pass through. shall be. After the ring packing 10 is fitted, a ring packing presser 11 is attached to uniformly pressurize the ring packing 10. Since this ring packing presser foot 11 is necessarily a rigid body such as metal, it is divided into two halves as shown in FIG. Stop hole 11

Claims (1)

[Scope of Claims] 1. A ring packing having elasticity through which the valve stem head can pass, a releasable ring packing presser for the ring packing, and a ring packing presser for the ring packing press and the valve stem head. It consists of a pressurizing body that has the same elasticity as the ring packing and a crimping body that presses the pressurizing body between the key cap to be fixed. deforms in the axial direction of the valve stem and pressurizes the upper surface of the ring packing presser, pressurizes the ring packing installed between the valve stem and the ring packing presser, and seals leakage from that part. A device for preventing leakage from the valve stem of a valve. 2. Claim No. 2, characterized in that the ring packing or pressurizing body described in the preceding paragraph is inserted into the valve stem by cutting a part thereof, opening the cut part, and adhering the cut part. The device according to item 1.