JPS5938258Y2 - heat recovery tube - Google Patents

Description

[Detailed description of the invention] This invention is a heat-shrinkable tube that prevents dust, dirt, water, etc. from adhering to the inner and outer walls of the tube during storage or transportation, and keeps the inner and outer walls clean until use. Or it relates to a thermally expandable tube.

To prevent corrosion at the joints of steel pipes used for transporting gas, oil, water, etc., use heat-shrinkable tubes made of butyl rubber or the like, or provide an adhesive layer on the inner wall of heat-shrinkable tubes. A type of heat-shrinkable tube with a release paper temporarily attached in a spiral shape on the adhesive layer is used.

To cover the above-mentioned steel pipe connection portion with a heat-shrinkable tube, the tube is inserted into the steel pipe, adjacent steel pipes are welded together, and then the tube is set on the welded portion and heat-shrinked.

Furthermore, when piping steel pipes under a road, due to road usage hours, the tubes may be buried in the tubes after they have been welded to each other, and the tubes may be dug up again the next day to heat-shrink the tubes.

Heat-shrinkable tubes for corrosion protection of steel pipes are heat-shrinked on the welded joints between steel pipes as described above, but in the former type of conventional products, the inner wall surface of the tube was not protected at all and was exposed. Since the wire is still intact, dust, dirt, water, etc. are likely to adhere to it before it is heat-shrinked, and in the latter type, the peeling line is only temporarily attached to the adhesive layer, so the end may peel off due to vibrations, shocks, etc. during work. Like the former, dust, sand, water, etc. are likely to adhere to it.

On the other hand, heat-expandable tubes are often used for the inner lining of metal pipes, but there are no products that can keep the walls, especially the outer walls, clean until the time of use. The lining work had to be done after wiping the wall surface with a cloth, which was troublesome.

The present invention relates to a heat-recoverable tube with heat-shrinkable or heat-expandable properties devised to solve the problems of the conventional products mentioned above. The protective sheet is bent at at least one opening of the tube body and guided onto the outer wall surface, and both ends of the protective sheet are abutted or overlapped on the outer wall surface or near the opening to cover the entire outer wall of the tube body. Both ends of the protective sheet are fixed to each other at the abutted or overlapped portion, and the entire tube body is wrapped and covered with the protective sheet.

The heat-recoverable tube body in this invention is made of polyvinyl chloride, polyethylene, cross-linked polyethylene, polypropylene,
A single-layer type made by processing a tube of plastics such as fluorocanipone polymer, or rubber such as natural rubber, silicone rubber, or ethylene-propylene copolymer rubber so that it can be heat-shrinked or heat-expanded, or the single-layer type. Any multilayer type can be used in which an adhesive layer such as a pressure-sensitive adhesive, a self-adhesive adhesive, or a heat-activated adhesive is provided on the inner or outer wall.

In addition, the protective sheet is flexible so that it will not tear or tear when bent at the opening of the heat-recoverable tube body, and specific examples include plastics such as polyethylene, polyester, and polyvinyl chloride. Examples include sheets, nonwoven fabrics, cloth, and paper.

In addition, when using a multi-layer type tube body with a constantly adhesive adhesive layer, the protective sheet should be a non-adhesive sheet such as a polyethylene sheet, or a silicone protective sheet. It is preferable to use a sheet whose surface in contact with the adhesive layer has been subjected to at least a slight release treatment using a release treatment agent such as a resin, since the peeling operation when removing the protective sheet can be carried out smoothly.

In the present invention, in order to cover the entire inner wall of the tube body using the above-mentioned protective sheet, (1) Wrap the sheet once along the inner wall surface of the tube body, and match or overlap the ends of the sheet, and then (2) Wrap the sheet multiple times along the inner wall surface of the tube body; (3) Wrap the sheet in advance to match the inner diameter of the tube body. This is carried out by making a cylindrical body having the same outer diameter and inserting the cylindrical body into the tube body.

The protective sheet that has covered the entire inner wall of the tube body by the above method is then bent at one or both openings of the tube body and guided onto the outer wall surface, and its both ends are bent on the outer wall surface of the tube body or near the opening. After covering the entire outer wall by abutting or overlapping, they are fixed to each other at the abutting or overlapping portions.

The fixing methods include (1) adhesive fixing with one-sided adhesive tape, double-sided adhesive tape, adhesive, etc., (2) tightening fixing with a rubber ring, (3) fusion fixing with heat sealing, (4) This is accomplished by using projections and depressions provided in advance on both ends of the protective sheet that fit together with each other, or by fitting and fixing them using fasteners.

Hereinafter, an example of the present invention will be explained with reference to the drawings.

FIG. 1 shows a heat-recoverable tube according to the present invention, in which the entire inner wall of the tube body 1 is covered with a protective sheet 2.

As shown in FIG. 2, the protective sheet 2 is wound once along the inner wall surface of the tube body 1, and the ends are butted against each other.
A single-sided adhesive tape 3 is adhered onto the abutted portion.

The protective sheet 2 that has covered the entire inner wall of the tube body 1 in this way is bent at both openings of the tube body 10, guided onto the outer wall surface, and both ends thereof are abutted on the outer wall surface.

As a result, the entire outer wall of the tube body 1 is covered with the protective sheet 2.

Note that the abutting portions of the standard sheet 2 are fixed with a single-sided adhesive tape 4.

FIG. 3 shows another example, in which a protective sheet 2 formed into a cylindrical body having the same outer diameter as the inner diameter of the tube body 1 is inserted into the tube body 1 in advance.

The protective sheet 2 is bent at both openings of the tube body 1 and guided onto the outer wall surface, both ends of which are overlapped, and then a single-sided adhesive tape 4 is adhered to the overlapping portion.

Note that 5 is an adhesive layer provided on the tube body 1, and the surface of the protective sheet 2 that comes into contact with the adhesive layer 5 is coated with silicone resin, dried, and subjected to a peeling treatment.

In Fig. 3, the protective sheet was previously made into a cylindrical body with the same outer diameter as the inner diameter of the tube body 1, but in the present invention, the protective sheet was made into a cylinder with an outer diameter that was slightly thicker or slightly smaller than the inner diameter of the tube body 1. It is also possible to use a protective sheet in the form of a cylinder having an outer diameter of .

FIG. 5 shows still another example, in which the protective sheet 2, which has been made into a cylindrical body having an outer diameter the same as the inner diameter of the tube body 1, is bent at one opening inserted into the tube body 1, and the outer wall is bent. After the entire surface is covered, both ends are brought together near the other opening of the tube body 1 and fixed by heat sealing.

6 is a heat seal part. Although not shown, when heat-sealing, if you insert a string-like object that can withstand the temperature during heat-sealing so that one end is exposed to the outside, it can be used as a grip when removing the protective sheet. This is preferable because it can be done.

Next, FIG. 7 shows an example suitable for cases where there is a risk of water adhesion.

A protective sheet 2 made of cloth or paper is wrapped in two layers along the inner wall surface of the tube body 1 (see Fig. 8).The protective sheet 2 is further folded at both openings of the tube body 10, and the Both ends are butted together and one-sided adhesive tape 4
Fixed by

In this case, both ends of the protective sheet 20 may be overlapped as shown in FIG. 3 and tightened with rubber rings.

In the heat-recoverable tube of the present invention, the protective sheet is removed immediately before the tube body is heat-shrinked or heat-expanded.

In addition, in the above-mentioned examples, the tube body 1
Although the protective sheet 2 is in close contact with the inner and outer wall surfaces and the adhesive layer, in the present invention, it is not necessarily necessary to have the protective sheet 2 in close contact with these, and there is no problem even if there is a gap between the two, and it is necessary to It is sufficient to cover the inner and outer wall surfaces and the adhesive layer with a protective sheet so as to isolate them from the outside air.

Since the present invention is constructed as described above, (1) it can effectively prevent dust, dirt, water, etc. from adhering to the wall surface, so it can be tightly adhered or adhered to the adherend during use; It is also useful for other uses, such as electrical insulation of conductor connections of electric wires, protection of various pipes on ships, etc.
It has the following effects.

[Brief explanation of drawings]

Figures 1.3, 5, and 7 are longitudinal cross-sectional views showing an example of the heat-recoverable tube according to the present invention cut into a semi-cylindrical shape along its length, and Figure 2 is A of Figure 1. - A cross-sectional view taken along line A, Figure 4 is a cross-sectional view taken along line B-B in Figure 3, Figure 6 is a cross-sectional view taken along line C-C in Figure 5, and Figure 8 is a cross-sectional view taken along line D-D in Figure 1. FIG. 1...Tube body, 2...Resuscitation sheet.

Claims (1)

[Scope of utility model registration request] The entire inner wall of the heat-recoverable tube body is covered with a long protective sheet, and the protective sheet is bent at at least one opening of the tube body and guided onto the outer wall surface, and both ends of the protective sheet are placed on the outer wall surface or the opening. A heat-recoverable tube comprising a protective sheet covering the entire outer wall of a tube body by abutting or overlapping near the abutting or overlapping parts, and fixing both ends of a protective sheet to each other at the abutting or overlapping parts.