JPH109448A - Synthetic resin pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To join pipes together simply by laminating synthetic resin having high organic solvent resistance in a separable condition on the outer periphery of a synthetic resin pipe having low organic solvent resistance such as polyolefinic synthetic resin. SOLUTION: In a synthetic resin pipe 1, its outer layer 3 made of synthetic resin having high organic solvent resistance is laminated on the outer peripheral surface of a pipe main body 2 made of polyolefinic synthetic resin in a condition which is separable from the pipe main body 2. In the case of a laminating method, when extrusion molding is carried out using a double layer pipe die, the temperature of the confluent part of polyolefinic synthetic resin as the pipe main body 2 and synthetic resin having organic solvent resistance as an external layer 3 is reduced so as to prevent both synthetic resin from fusing each other. It is thus possible to join pipes 1 together simply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin pipe, and more particularly, to a synthetic resin pipe used for water supply, gas, sewage, and the like.

[0002]

2. Description of the Related Art Conventionally, pipes made of polyolefin-based synthetic resins such as polyethylene and polybutene have been widely used as pipes for water supply and the like. However, since these polyolefin-based synthetic resins have the property of penetrating certain organic solvents such as gasoline, kerosene, and trichlene (trichloroethylene), when used on the ground contaminated with such organic solvents. Required the use of a sheath tube or the like.

Although it is possible to manufacture the entire pipe with a synthetic resin having excellent organic solvent resistance, there are problems in cost and joining, etc., and it is limited to special applications. Did not.

Accordingly, the present invention is to provide a synthetic resin pipe which is excellent in organic solvent resistance and which can be easily joined to a conventional pipe made of a polyolefin-based synthetic resin. The purpose is.

[0005]

In order to achieve the above object, a synthetic resin pipe according to the present invention is provided on an outer peripheral surface of a synthetic resin pipe body having poor organic solvent resistance, such as a polyolefin synthetic resin, with an organic solvent resistant pipe. It is characterized in that synthetic resins having excellent properties are laminated in a peelable state.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is an end view showing an example of the synthetic resin pipe of the present invention, and FIG. 2 is a half cross-sectional view showing a state where a synthetic resin layer (outer layer) having excellent organic solvent resistance is peeled off.

The synthetic resin pipe 1 has an outer layer 3 made of a synthetic resin having excellent organic solvent resistance on the outer peripheral surface of a pipe main body 2 made of a polyolefin synthetic resin in a state where it can be peeled off from the pipe main body 2. It is a laminate.

The pipe main body 2 is made of a conventional polyolefin-based synthetic resin such as polyethylene or polybutene formed into a pipe by the same extrusion molding method or the like as the conventional one. The strength of the synthetic resin pipe 1 is as follows. Most of this is borne by the pipe body 2.

As the synthetic resin which forms the outer layer 3 and has excellent organic solvent resistance, an appropriate resin can be used in an appropriate thickness depending on the kind of the organic solvent at the time of use. For example, the above-mentioned gasoline, kerosene, trichlene Nylon or the like, which is resistant to permeation and does not penetrate, can be used.

As a method of laminating the outer layer 3 on the outer peripheral surface of the pipe main body 2 in a releasable manner, an appropriate method can be selected according to the diameter of the pipe 1 and the like. For example, when extrusion molding is performed using a conventionally used two-layer pipe die, the temperature of the junction of the polyolefin-based synthetic resin that forms the pipe body 2 and the synthetic resin that forms the outer layer 3 and has excellent organic solvent resistance is used. To prevent the two from fusing together, or to set the junction of both as far as possible at the tip of the base,
It can be carried out by cooling immediately after the merging so as not to give time for melting and fusing to both. In the case of extrusion molding using a two-layer pipe die, the extrusion is performed in consideration of the extrusion performance of both resins.

Further, a film made of a synthetic resin having excellent organic solvent resistance may be wound around the outer peripheral surface of the pipe body 2 formed in advance. The film may be formed in a cylindrical shape, and the film may be shrunk by inserting the pipe body 2 formed in advance into the cylindrical shape.

Regardless of which lamination method is adopted, it is necessary to keep the outer layer 3 from the outer peripheral surface of the pipe main body 2 with a small force. That is, as shown in FIG. 2, a cut 4 having an appropriate depth is formed in a portion of the outer layer 3 at a predetermined position of the tip portion of the synthetic resin pipe 1 with a cutter or the like, so that the outer layer 3 at the tip portion of the pipe is peeled off. To be able to do.

By exfoliating the outer layer 3 and exposing the pipe main body 2 made of a polyolefin-based synthetic resin as described above, it becomes possible to perform the same fusion bonding of EF, HF, bat, etc. as in the conventional case, and to prevent organic resistance. The outer layer 3 made of a synthetic resin having excellent solvent properties does not hinder the fusion work, and the piping work can be easily performed by the same joining method as before.

[0014]

As described above, according to the synthetic resin pipe of the present invention, piping equipment excellent in organic solvent resistance can be formed without using a complicated method such as a sheath pipe. By peeling off the outer layer, joining can be easily performed by the same joining method as before, so that piping work can be easily performed. In addition, since the pipe main body is formed of a polyolefin-based synthetic resin, a synthetic resin pipe excellent in organic solvent resistance can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is an end view showing an example of a synthetic resin pipe of the present invention.

FIG. 2 is a half sectional view showing a state where an outer layer is peeled off.

[Description of Signs] 1 ... Synthetic resin pipe, 2 ... Pipe body, 3 ... Outer layer, 4
... break

Claims (1)

[Claims] 1. A synthetic resin characterized in that a synthetic resin excellent in organic solvent resistance is laminated on an outer peripheral surface of a synthetic resin pipe body inferior in organic solvent resistance such as polyolefin synthetic resin in a releasable state. Resin pipe.