JPS58102618A - Cutting method of tube applied with corrosion-proof coating on the outer surface - Google Patents

Abstract

PURPOSE:To prevent the peeling of a corrosion-proof coating in a corrosion- proof region, by cutting a tube while winding a strip member on the outer circumference at the cutting section and removing the coating from the cutting position to the winding position. CONSTITUTION:A strip member 6 such as a steel band or an adhesive tape is wound on the outer circumference of a corrosion-proof member 3 while leaving a region 4 from the cutting position A which will be the jointing portion 2a after cutting. Then it is cut by a cutter (not shown) at the position A. Thereafter a corrosion-proof member 3 at the region 4 is removed to provide the joint portion 2a after the cutting. When guiding the edge of the strip member 6 and cutting the coating 3 by means of a cutter, the coating member 3 in the region 4 can be removed easily.

Description

[Detailed description of the invention] The present invention relates to a method for cutting an externally anti-corrosion cladding pipe.

In conventional external anti-corrosion cladding pipes, the anti-corrosion coating material is attached to the outside surface of the pipe by giving it adhesive properties, so even if the pipe is cut, the anti-corrosion coating material may be accidentally peeled off in the necessary areas. That was not the case. However, such anti-corrosion coatings are expensive, so in order to reduce the cost of anti-corrosion coatings, a band-shaped anti-corrosion coating made of synthetic resin such as polyethylene or vinyl chloride is extruded using an extruder, and this anti-corrosion coating is Wrap the material around the outer surface of the pipe and
) is considered to prevent peeling from the tube by utilizing the contraction during cooling and hardening. However, in the case of external anti-corrosion cladding pipes wrapped with non-adhesive anti-corrosion coating material, the anti-corrosion coating peeled off from the cut surface when the pipe was cut, especially when the strip-shaped anti-corrosion coating material was wound in a spiral shape. In some cases, there is a risk that peeling may progress.

In view of these problems, the present invention aims to provide a pipe cutting method that can prevent the anticorrosive coating from peeling off.

In the method of the present invention, prior to cutting the tube, a band-like body is wrapped around the outer periphery of the area corresponding to the pottery in the area where the anticorrosion coating should be applied after the tube is cut, and then the tube is cut at a predetermined position. The anti-corrosion coating material from the area to the position of the band-shaped body is removed, thereby preventing the anti-corrosion coating material from peeling off in the area of the anti-corrosion coating by the band-shaped body.

An embodiment of the present invention will be described below based on the drawings. (
Reference numeral 1) is an external anticorrosive cladding tube, and a band-shaped anticorrosive coating material (3) is spirally wound around the outer surface of the tube except for the joint 5(2) at one end. This anti-corrosion coating (2) Material (3) F! It is made of metallic resin such as polyethylene or vinyl chloride, and is extruded using an extruder when being wrapped.
It is wrapped around the outer surface of the tube and is attached to prevent it from peeling off from the outer surface of the tube due to shrinkage during cooling and hardening. An attempt is made to cut such an externally anti-corrosion coated pipe (1) at the position indicated by the dashed line where the anti-corrosion coat material (3) is wound. Therefore, as shown in Fig. 2, first open a region (4) that will become the joint (2a) of the pipe after cutting from the cut pipe position, and then cover it with a belt-like material (6) such as a steel band or adhesive tape as an anti-corrosion coating. Wrap it around the outer circumference of (3) and tighten it to fix it. That is, the band (6) is wrapped and fixed in advance around the outer periphery of the portion corresponding to the end of the anti-corrosion coating area (5) of the cut pipe. After that (4
) position with a cutter (not shown). Then the third
As shown in the figure, by removing the anti-corrosion coating material (3) in area # (4), a joint portion (2a) of the pipe after cutting is provided. At that time, use a cutter to prevent corrosion using the edge of the strip (6) as a guide. By cutting the IL covering material (3), the anticorrosion covering material (3) in this region (4) can be easily and cleanly removed, so that the cutting edge does not get in the way during joining (3). ) According to the method for cutting an externally anti-corrosion coated pipe of the present invention, as is clear from the above explanation, prior to cutting the pipe, a band-like member is placed on the outer periphery of the portion corresponding to the end of the 1 m area of the anti-corrosion coated pipe after cutting. Since the tube is cut after being wrapped, the anti-corrosion coating area is covered by the band-like material.
It is possible to completely prevent the peeling of the anti-corrosion coating material during the cutting process, and to remove the anti-corrosion coating material from the cutting position to the position of the strip, so that the anti-corrosion coating material can be removed and the area can be accurately and accurately removed. Easy to form.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view of the tube before cutting, FIG.
i is a front view after cutting the tube. (1)... External anticorrosion cladding tube, (2) (2a)... joint, (3)... anticorrosion coating material, (5)... anticorrosion coating area, (6)... belt shape body agent mori tree
Yoshihiro (4)

Claims (1)

[Claims] 1. The pipe is cut after wrapping a band-like body around the outer periphery of a portion corresponding to the end of the anti-corrosion coating area after cutting the pipe, and removing the anti-corrosion coating material from the cutting position to position 11 of the band-like body. How to cut the externally anti-corrosion coated pipe.