JPH10238687A - Riser pipe for connecting gas meter and its riser pipe - Google Patents

Abstract

(57) [Abstract] [Purpose] A riser pipe for connecting a gas meter and a riser pipe for easily connecting a buried plastic pipe underground to a gas meter on the ground without a problem of electric corrosion without providing an insulating joint as in the past. It provides a tube. [Structure] A steel pipe connected to one end of a joint and a plastic pipe connected to the other end of the joint. The end of the steel pipe is connected to a supply gas meter on the ground, and the end of the plastic pipe is buried underground. Connected to the pipe, the plastic pipe is raised from the ground to the ground, and the outer surface of the plastic pipe part raised above the ground is covered with a protective pipe that does not conduct electricity to the soil and is connected to a gas meter connection Riser piping. In addition, one end side has a connection portion for sealing connection with the steel pipe, the other end side is connected to the plastic pipe, and a metal joint provided with a connection portion connected to the protection tube at the end, and at the other end of the joint. A riser tube for gas meter connection, comprising: a protective tube which is connected to cover the outer surface of the plastic tube and is not electrically connected to the soil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas meter connecting riser pipe for connecting a plastic pipe buried underground to a gas meter on the ground, and a riser pipe thereof.

[0002]

2. Description of the Related Art Conventionally, a connection between an underground plastic pipe and a gas meter on the ground is made by connecting a metal pipe to the underground plastic pipe, starting the metal pipe on the ground, and connecting it to a gas meter on the ground. I was Also, as a joint for connecting a plastic pipe and a metal pipe, the present applicant has devised a practically-opened Japanese Utility Model Application No. 6-2.
There is a pipe joint that connects a plastic pipe and a metal bellows pipe disclosed in Japanese Patent No. 0987. For this product, a metal bellows tube and a plastic tube are attached from the inner surfaces of both ends of the joint, a metal stiffener is inserted over the inner surfaces of both attached tubes, and the diameter of the metal stiffener is expanded from the inner peripheral side to make a metal tube. The bellows tube and the plastic tube are simultaneously compressed and connected and fixed to the inner peripheral surface of the joint.

[0003]

When connecting from underground to a gas meter on the ground, the metal pipe has a problem of corrosion due to being buried in the ground, such as macrocell corrosion generated between soil and concrete. For this purpose, various anti-corrosion measures must be taken, such as providing a resin film covering the buried portion of the metal pipe, or providing an insulation joint on the ground portion.
In addition, regular security inspections are required for this problem.

In the above-mentioned pipe joint, a plastic pipe and a metal bellows pipe are compressed together and sealed and fixed to the inner peripheral surface of the joint by one stiffener. On the other hand, if this is used for the riser pipe for connecting the gas meter, the gas meter must be fixed to the building etc. separately from the pipe, and the fixing means of the gas meter alone is required separately. is there.
The present invention solves the above-mentioned problems, eliminates the problem of electrical corrosion without providing an insulating joint, and can easily connect a gas meter connecting riser pipe from a buried plastic pipe underground to a gas meter on the ground as in the related art. And a riser tube thereof.

[0005]

The gist of the present invention consists of a steel pipe connected to one end of a joint and a plastic pipe connected to the other end of the joint, and the end of the steel pipe is a supply gas meter on the ground. The end of the plastic pipe is connected to an underground plastic pipe, and the plastic pipe is raised from the ground to the ground, and the outer surface of the plastic pipe part raised above the ground is connected to the soil. It is a riser pipe for gas meter connection characterized in that it is covered with a protective tube that does not conduct electricity and is piped.

[0006] One end has a connection portion for hermetically connecting to the steel pipe, and the other end has an annular concave / convex groove on the inner surface to insert a plastic tube and insert a metal stiffener into the inner surface of the plastic tube. A metal joint provided with a connecting portion for connecting the plastic stiffener by expanding the diameter of the metal stiffener and connecting with the protective tube at an end portion; a steel pipe connected to one end of the joint and being piped to a gas meter; A plastic pipe that is raised from the ground and connected to the other end of the joint, a protective pipe that is connected to the other end of the joint and covers the outer surface of the plastic pipe, and that is not electrically connected to soil; It is a riser pipe for gas meter connection characterized by comprising.

In the above, the protective tube covering the outer surface of the plastic tube is preferably made of a flame-retardant resin material of an electrically poor conductor. Further, as the protective tube for covering the outer surface of the plastic tube, an outer resin-coated steel tube can be used. In this case, the outer surface of the steel pipe may be covered with a resin film, and a resin cap may be provided at the end of the buried portion to seal with the plastic pipe so that the buried end does not come into contact with the soil.

[0008]

According to the present invention, the plastic pipe portion is connected to a buried plastic pipe in the ground and is set up from the ground to the ground to be piped. Therefore, since the steel pipe or metal joint connected to the gas meter is piped without contacting the underground soil, problems such as potential difference corrosion caused by the metal pipe contacting the soil do not occur. In addition, the plastic pipe part that is set up on the ground is covered with a protective pipe of an electrically defective conductor and does not conduct to the soil, and it is not protected from the external environment. Absent. Further, since the stiffener is expanded and fixed to the inner surface of the joint only in the plastic pipe portion, the connection and connection can be reliably performed according to the diameter and thickness of the plastic pipe. The outer surface of the plastic tube is protected by a protective tube and has fire resistance. Therefore, there is no need to provide an insulation joint in the conventional ground piping or to perform a corrosion protection treatment so that metal pipes and joints are covered with a resin so that they do not come into contact with the soil, and piping with the gas meter can be easily performed. You.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a gas meter connecting riser pipe 10 of the present embodiment piped to the primary side of a gas meter 8. The riser pipe 10 has a plastic pipe 30 at the lower part of the joint 20 and an outer resin coating on the upper part of the joint 20. Steel pipe 40
The lower plastic pipe 30 is connected to a buried plastic pipe 5 underground by a plastic pipe connection joint 6, and is raised on the ground. The portion of the plastic tube 30 rising on the ground is covered with another protective tube 50 so that the outer surface is not exposed. The upper outer resin-coated steel pipe 40 is connected to the inlet connection port of the gas meter 8 via the cock 1 and the elbow 2. The outlet side of the gas meter 8 is connected to the outer resin-coated steel pipe 4 through the elbow 3 and the like in the same manner as in the past, and is piped in the building through the outer resin-coated joint 9 in the ground, and is connected to each supply gas appliance and the like in the building. Supplied.

FIG. 2 is a half sectional view of a gas meter connecting riser tube 10 showing one embodiment of the present invention. In the figure,
The outer resin-coated steel pipe 40 connected to the upper side of the joint 20 has a resin film 41 made of vinyl chloride applied to the outer surface thereof, and is connected to the joint 20 by a pipe taper screw 42. Fitting 20
An annular concave groove 23 is provided on the inner surface of the upper end portion, and a watertight packing 43 is attached to hermetically seal with the resin film 41 of the outer resin-coated steel pipe 40. The outer resin-coated steel pipe 40 to be connected to the joint 20 may be a bare steel pipe, and the connection between the joint 20 and the steel pipe 40 is not only the above-described tapered screw connection for pipes but also a conventionally known mechanical connection structure for connecting without providing a screw. May be connected. The length of the outer resin-coated steel pipe 40 from the joint 20 is about 1M, and the upper end is connected to the gas meter 8 via the cock 1, the elbow 2 and the like as shown in FIG.

An annular concave / convex groove 24 for compressing the end of a plastic tube 30, a seal portion 26 provided with a seal packing 25, a female screw 27, and a watertight packing 28 are mounted on the lower inner surface of the joint 20. A plastic tube 30 having a metal stiffener 31 inserted therein is inserted into this portion, and a rubber bulge expanding tool (not shown) is inserted from the lower end side of the plastic tube 30 to expand the stiffener 31 so that the plastic tube 30 is removed. It is compressed and fixed in the annular groove 24 on the inner surface of the joint. When the stiffener 31 is expanded, the seal packing 25 is also compressed at the same time, and the joint 20 and the plastic pipe 30 are sealed. Plastic tube 30
The length from the joint 20 is about 400 mm, and the lower end is connected to the plastic pipe 5 buried underground via the joint 6 for connecting plastic pipes, and stands up on the ground.

Reference numeral 50 denotes a protective tube connected to the female thread 27 of the joint 20. In this embodiment, an outer resin-coated steel tube is used.
Cover the outer surface of the portion of the plastic tube 30 that is set up on the ground to protect it from deterioration due to ultraviolet rays, damage due to external force, and heat from fire in the event of fire being transmitted to the plastic tube 30 and leaking out. I have. For this, a vinyl chloride pipe, a cement pipe, an asbestos pipe or the like may be used instead of the steel pipe. One end of the protection tube 50 is a watertight packing 2 of a joint.
The other end is screwed with a cap nut 51 made of resin to compress the packings 52 and 53, thereby sealing the outer surface of the plastic tube 30. The sealing portion formed by the cap nut 51 is buried underground.

Therefore, according to the present embodiment, even if the gas in the plastic pipe 30 leaks due to some influence at the connection part of the plastic pipe 30 with the joint 20 or at the rising part of the pipe 30 on the ground, the protection pipe 50 is not damaged. Do not leak outside. Further, the electrical insulation between the underground portion, the joint 20 and the outer resin-coated steel pipe 40 can be achieved by sealing the end portion of the protective tube 50 to the external environment with a resin cap nut 51 packing 52 even if the protective tube 50 is an outer resin-coated steel pipe. So that insulation is achieved. In addition, the protective tube 50 can be formed of a flame-retardant electrically defective conductor such as a vinyl chloride resin. In this case, even if the cap nut 51 is omitted, the electrical connection between the soil and the metal joint 20 can be prevented. No conduction occurs.

[0014]

As described above, according to the present invention, the metal pipe is connected to the gas meter without contacting the buried soil.
Therefore, the problem of corrosion such as macrocell corrosion is eliminated, and the plastic pipe set up on the ground is protected and shielded from the external environment, and there is no problem such as deterioration of ultraviolet rays. Therefore, there is no need to perform anticorrosion treatment such as providing an insulating joint or coating a metal tube with a resin, and the piping with the gas meter can be easily performed similarly to the conventional method. In addition, the connection between the joint and the plastic pipe can be securely fixed according to the diameter and thickness of the plastic pipe.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a state where a gas meter connection riser pipe according to an embodiment of the present invention is piped.

FIG. 2 is a half sectional view showing a gas meter connection riser pipe according to an embodiment of the present invention.

[Description of Signs] 1 cock 2, 3 elbow 4, 40 outer resin-coated steel pipe 5 buried plastic pipe 6 plastic pipe connection joint 8 gas meter 9 outer resin-coated elbow joint 10 gas meter connection riser pipe 20 joint 23 annular concave groove 24 joint Annular groove 25 Seal packing 26 Seal part of joint 27 Female thread of joint 28 Watertight packing 30 Plastic pipe 31 Metal stiffener 41 Resin film 42 Taper screw for pipe 43 Watertight packing 50 Protective pipe 51 Cap nut 52, 53 Packing

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideo Nozaki 2 Daifuku, Kuwana-shi, Mie Pref. Hitachi Metals, Ltd. Kuwana Plant (72) Inventor Katsumi Sakamoto 3-7-1 Nishishinjuku, Shinjuku-ku, Tokyo Hitachi Metals Piping equipment division

Claims (4)

[Claims] 1. A steel pipe connected to one end of a fitting, and a plastic pipe connected to the other end of the fitting. An end of the steel pipe is connected to a supply gas meter on the ground, and an end of the plastic pipe is connected to a ground gas meter. The plastic pipe is connected to an underground plastic pipe, and the plastic pipe is set up from the ground to the ground, and the outer surface of the plastic pipe part set up on the ground is covered with a protective pipe that is not electrically connected to the soil. A riser pipe for gas meter connection characterized by being piped. 2. One end has a connecting portion for hermetically connecting to a steel pipe, and the other end has an annular concave and convex groove on an inner surface, inserts a plastic tube, and inserts a metal stiffener on an inner surface of the plastic tube. A metal fitting provided with a connecting part for connecting a plastic pipe by expanding a metal stiffener and connecting it to a protection pipe at an end; a steel pipe connected to one end of the fitting and piped to a gas meter; A plastic tube that is raised from the ground and connected to the other end of the joint, a protective tube that is connected to the other end of the joint to cover the outer surface of the plastic tube, and that is not electrically connected to soil; A riser tube for connecting a gas meter, comprising: 3. The riser tube for connecting a gas meter according to claim 1, wherein the protective tube covering the outer surface of the plastic tube is made of a flame-retardant resin material. 4. The protective tube covering the outer surface of the plastic tube is made of an outer resin-coated steel tube.
The riser pipe for connecting a gas meter according to any one of claims 1 to 3.