JPH10205659A - Fluid conducting buried coated steel pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a leak of fluid out of a buried coated steel pipe early and automatically. SOLUTION: A hollow layer 4 continued in the longitudinal direction is installed in a resin coating layer 3 in a fluid conducting buried coated steel pipe 10 formed with this resin coating layer 3 on the circumference of a steel pipe 1. In addition, a hollow chamber 11 communicating to this hollow layer 4 is formed in the proper spot of a connection of the buried coated steel pipe 10, and then a sensor 12 detecting a fluid leaking from the steel pipe 10 and collected in the hollow chamber 11 by way of the hollow layer 4, is installed in this hollow chamber 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buried coated steel pipe for fluid conduction, in which a sensor for detecting fluid leaking from the buried coated steel pipe is provided in a buried coated steel pipe through which a fluid such as gasoline flows. is there.

[0002]

2. Description of the Related Art Conventionally, in a buried coated steel pipe through which a fluid flows inside, there are various factors such as damage to the coated steel pipe due to a mistake during construction, and corrosion from inside the pipe due to the influence of a fluid flowing inside. Corrosion of the steel pipe may progress, and as a result, the fluid flowing inside may flow out to the soil. In this case, if the escaping fluid is gasoline or the like, fire and soil contamination will progress, and it is necessary to detect the fluid early.

[0003]

As described above, when a fluid flowing inside leaks due to damage to a buried coated steel pipe, detection of this leak has conventionally relied on human monitoring. Can be found relatively early, but it is difficult to find when the amount of leakage is very small.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and provides a buried coated steel pipe for fluid conduction which can automatically and automatically detect leakage of fluid from a buried coated steel pipe. It is intended to be.

[0005]

In order to achieve the above object, according to the present invention, a hollow layer continuous in the longitudinal direction is provided on a resin coating layer of a buried coated steel pipe having a resin coating layer formed on the outer periphery of a steel pipe. I have to do that. A hollow chamber communicating with the hollow layer is formed at an appropriate position in the connection portion of the buried coated steel pipe for fluid conduction, and a fluid leaking from the buried coated steel pipe and remaining in the hollow chamber through the hollow layer is detected in the hollow chamber. It has a sensor.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A buried coated steel pipe for fluid conduction according to the present invention is characterized in that a hollow layer continuous in the longitudinal direction is formed on the resin coating layer of the buried coated steel pipe for fluid conduction having a resin coating layer formed on the outer periphery of the steel pipe. It is provided. In the fluid-coated buried coated steel pipe of the present invention, the number of hollow layers formed in the resin coating layer is not particularly limited, but even if any position on the circumference of the buried coated steel pipe is corroded, a part of the leaked fluid is It is necessary to flow as much as possible. If the number is small, care should be taken to increase the area facing the outer peripheral surface of the steel pipe as much as possible. The cross-sectional shape and the cross-sectional area of the hollow layer are not particularly limited.

[0007] Then, a hollow chamber communicating with the hollow layer is formed at an appropriate position of the connection portion of the buried coated steel pipe, and a fluid leaking from the buried coated steel pipe and remaining in the hollow chamber through the hollow layer is detected in this hollow chamber. By providing a sensor, the fluid flowing through the hollow layer is stored in the hollow chamber and detected by the sensor.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A buried coated steel pipe for fluid conduction according to the present invention will be described below with reference to an embodiment shown in FIGS. FIG. 1 is a cross-sectional view showing one embodiment of a buried coated steel pipe for fluid conduction according to the present invention, FIG. 2 is an explanatory view of a method of manufacturing a buried coated steel pipe for fluid conduction according to the present invention, and FIG. FIG. 4 is a schematic diagram of a sensor installation portion of the buried coated steel pipe for fluid conduction according to the present invention when the die is viewed from the outlet side.

In FIG. 1, reference numeral 1 denotes a steel pipe, and an adhesive layer 2 such as a modified polyethylene
, A resin coating layer 3 of, for example, polyethylene is formed. In the buried coated steel pipe 10 of the present invention, 16 hollow layers 4 continuous in the longitudinal direction are provided in the resin coating layer 3, for example, at equal angular positions on the circumference.

In manufacturing the above-described buried coated steel pipe 10 of the present invention, for example, a round die 5 as shown in FIG. 2 using a round die 5 having a molded portion 5a of a hollow layer 4 at an outlet as shown in FIG. It may be manufactured by a die forming method.

In FIG. 4, reference numeral 11 denotes a hollow chamber provided at the connection portion of the above-mentioned buried coated steel pipe 10 of the present invention, and this hollow chamber 11 communicates with the hollow layer 4 of the buried coated steel pipe 10 and the inner surface of the steel pipe 1. Not in communication with Therefore, in the case where, for example, gasoline flowing inside due to corrosion or the like of the steel pipe 1 leaks,
Part of the leaked gasoline passes through the hollow layer 4 and the hollow chamber 11
Will accumulate. The buried coated steel pipe 10 of the present invention has a hollow layer 4 by providing a sensor 12 in a hollow chamber 11.
A part of the leaked gasoline accumulated in the hollow chamber 11 through the sensor is detected by a sensor 12 facing the hollow chamber 11.

In order to confirm the effects of the present invention, a buried coated steel pipe 10 (steel pipe 1: outer diameter = 89.1 mm, wall thickness = 4.2)
mm, adhesive layer 2: denatured polyethylene, resin coating layer 3: polyolefin resin, thickness = 2 mm, hollow layer 4: transverse section 1
A hollow part 11 communicating with the hollow layer 4 is provided at a rectangular (mm × 2 mm, 16 angularly equiangular position) connection part, and a sensor 12 is installed in the hollow part 11 according to the present invention. Using the coated steel pipe 10, an experiment for confirming the outflow phenomenon of water was performed.

The experiment assumes that the buried coated steel pipe 10 of the present invention has corroded, and has a diameter of 1 through the buried coated steel pipe 10.
This was performed by making a hole of 0 mm and flowing water inside the buried coated steel pipe 10. As a result, the water flowed to both the outside and the hollow layer 4 provided in the resin coating layer 3, and the water flowing in the hollow layer 4 was collected in the hollow chamber 11 provided in the connection portion and could be detected by the sensor 12. . From the above, it has been found that even when the steel pipe is corroded and the fluid flowing inside leaks, the leak of the fluid can be easily detected by the present invention.

[0014]

As described above, according to the present invention,
Even if the fluid flowing inside leaks, a part of the leaked fluid will flow through the hollow layer provided in the resin coating layer of the buried coated steel pipe, and the fluid leaks quickly and automatically. Can be detected.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a buried coated steel pipe for fluid conduction according to the present invention.

FIG. 2 is an explanatory view of a method of manufacturing a buried coated steel pipe for fluid conduction according to the present invention.

FIG. 3 is a view when the forming die of FIG. 2 is viewed from an outlet side.

FIG. 4 is a schematic explanatory view of a sensor installation part in the buried coated steel pipe for fluid conduction of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steel pipe 3 Resin coating layer 4 Hollow layer 11 Hollow chamber 12 Sensor

Claims (1)

[Claims] 1. A fluid-conducting buried coated steel pipe in which a resin coating layer is formed on the outer periphery of a steel pipe, wherein a continuous hollow layer is provided in the resin coating layer in a longitudinal direction, and a connection portion of the fluid-conducting buried coated steel pipe is provided in a proper position. A hollow chamber communicating with the hollow layer is formed, and a sensor for detecting a fluid leaking from the buried coated steel pipe and remaining in the hollow chamber through the hollow layer is provided in the hollow chamber. Buried coated steel pipe for conduction.