JPS6090739A - Covering method of t-shaped tube - Google Patents

Abstract

PURPOSE:To simply and exactly cover a T-shaped tube with a heat-shrinkable tape without causing deviation of the tape by a method in which a heat-shrinkable sheet is bonded to the branch tube-jointed portion and its neighbor of the main tube, and a heat-bond type heat-shrinkable tape is wound around the main tube and branch tube of the T-shaped tube while being heated. CONSTITUTION:A heat-shrinkable sheet 1 with an adhesive layer is closely bonded to the branch tube 24-jointed portion and its neighbor of the main tube 23. A tape 3 formed by laminating a heat-shrinkable bridged plastic tape 31 with a hot-bond type elastomer adhesive layer 32 having a shear strength of 0.005- 0.05kg/cm<2> at the maximum heat shrinkage temperature of the tape 31 is partly lapped with the sheet 1 and wound around the branch tube 24 and the main tube 23 while being heated and heat-shrunk for blose bonding. Good adhesion can be obtained even when heated since the elastomer adhesive is laminated on the tape 31, and crosswise shrinking deviation of the tape can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a T-shaped tube suitable for covering the outer peripheral surface of a T-shaped tube, particularly a T-shaped tube whose main tube and branch tubes are formed of small diameter tubes with an outer diameter of 8 inches or less. The present invention relates to a coating method.

Conventionally, the shape of pipes in heavy chemical factory plants, pipes for urban central heating, or pipes around pump stations for crude oil and natural gas transportation pipelines have been shaped like elbows,
There are many types of reducers, valves, T-shaped pipes, flange parts, etc., but when conventional heat-shrinkable sheathing materials are applied as they are to small diameter pipes among these irregularly shaped pipes, heat-shrinkable sheathing materials Due to its rigidity, it is not possible to align it sufficiently with the surface of the small diameter pipe, and even if it can be aligned, it is difficult to heat-shrink the length of the heat-sealing tape to bond and fix the heat-shrinkable coating material. The ratio of the heat-shrinkable covering material to the total length becomes extremely large, impairing the heat shrinkage of the heat-shrinkable covering material, making it difficult to obtain sufficient shrinkage adhesion.

In addition, when the heat shrinkage rate of the heat-shrinkable coating material is increased to improve adhesion, the heat-seal tape cannot withstand the shrinkage stress, resulting in the inconvenience of the edges shifting and, in some cases, peeling off. Ta. That is, if the irregularly shaped pipe to be coated is a T-shaped pipe that has branch pipes that branch out from the main pipe in a T-shape, a heat-shrinkable covering material with a high heat shrinkage rate is wrapped around it. When heat shrinkage is performed, the coating material that adheres to the periphery of the main pipe and branch pipes due to the heat shrinkage in the circumferential direction also causes a large contraction in the width direction of the coating material, resulting in T The problem is that the rising part of a branch pipe of a branch pipe slips away from the neck and a part of the main pipe around it, and it comes off from the neck of the pipe to be covered and its surroundings, or there are many problems around the neck. There was a problem in that wrinkles and voids were formed.

Furthermore, conventionally, when covering a deformed pipe with a heat-shrinkable sheathing material, the heat-shrinkable sheathing material is usually cut, and each of the cut sheets of the heat-shrinkable sheathing material is closely attached to a corresponding part of the deformed pipe. There were also problems such as the large amount of labor required for construction.

As a result of intensive research into solving the problems that occur when T-shaped pipes are coated with the above-mentioned heat-shrinkable (corrosion-proof) coating material, the present inventors first installed a heat-shrinkable sheet around the neck of the branch pipe. By joining the T-shaped pipe to a part of the main pipe and then wrapping the heat-shrinkable tape around the T-shaped pipe, the heat-shrinkable coating material can eliminate the shifting, peeling, and wrinkles that occur during heat shrinkage.
It was found that problems such as voids can be solved.

Furthermore, the adhesive layer of the heat-shrinkable tape is mainly composed of an elastomer material that can maintain a high shear strength related to the adhesive force even at the high temperatures at which the heat-shrinkable tape heat-shrinks. It has also been found that by employing a heat-adhesive adhesive layer, problems such as shearing, peeling, and wrinkling that occur in heat-shrinkable coating materials during heat-shrinking can be more effectively solved.

The present invention has been made based on the above findings, and is a method of covering a T-shaped pipe having branch pipes branching in a T-shape from a main pipe with a heat-shrinkable material. After adhering Sea I to the main pipe around the neck of the rising part of the branch pipe of the T-tube by heating it to cause heat shrinkage, heat it on one side of the crosslinked plastic layer that has heat shrinkability. An adhesive layer is provided, and the entire area or a partial area of the adhesive layer has a temperature of about 0.005 to 0.05 at a temperature at which the crosslinked plastic layer exhibits the largest heat shrinkage force.
Shear strength within kg/cJ (7) range (ASTM D10
02) A heat-shrinkable tape formed with an adhesive layer mainly composed of an elastomer material that can exhibit the adhesive strength shown in the above is partially overlapped with the heat-shrinkable sheet, and the main pipe and branches are bonded together. The present invention provides a method for covering a T-shaped pipe, which is characterized in that the main pipe and branch pipes are closely bonded by wrapping the material around the pipe while heating and tensioning the pipe to cause heat shrinkage.

The method for covering a T-tube of the present invention is to thermally bond a heat-shrinkable sheet with an adhesive layer to the main pipe around the neck of a branch pipe of the T-tube, and then apply the heat-shrinkable tape as described above. It is superimposed on a heat-shrinkable sheet and wrapped around the main pipe and branch pipes of the T-shaped pipe, and the heat-shrinkable tape has high adhesive strength at its heating shrinkage temperature.
According to the coating method of the present invention, there is almost no problem that the heat-shrinkable tape that has been heat-shrinked and brought into close contact with the surface of the T-tube shifts in the width direction or partially peels off.

Further, according to the method of covering a T-shaped tube of the present invention, as described above (
Since the coating is mainly made of heat-shrinkable tape, and the heat-shrinkable tape has high adhesive strength at its heat-shrinkage temperature, the relative amount of heat-sealing tape that inhibits heat-shrinkage can be reduced. As a result, it is possible to easily and reliably adhere the heat-shrinkable tape to the surface of the T-tube.

Furthermore, according to the T-tube covering method of the present invention, as described above, since the covering is mainly performed with a heat-shrinkable tape,
The construction work can be easily performed continuously.

Furthermore, according to the T-tube covering method of the present invention, prior to wrapping the heat-shrinkable tape, a heat-shrinkable sheet with an adhesive 6 layer is applied to the area around the neck of the branch pipe of the T-tube. Since it is thermally bonded to the pipe, it is possible to easily and reliably cover the main pipe portion around the neck of the branch pipe of the T-shaped pipe, which is difficult to cover.

EMBODIMENT OF THE INVENTION Hereinafter, the coating method of the T-shaped tube of this invention will be explained in detail based on the embodiment, referring to drawings.

First, the heat-shrinkable tape 3 used in the present invention will be explained. The heat-shrinkable tape 3, which is not shown in FIG. 1, is roughly as shown in FIG.
A heat-adhesive adhesive layer 32 is provided on one side of the holder.

The crosslinked plastic layer 31 may be formed from a conventionally known heat-shrinkable crosslinked plastic film or sheet, or a laminated sheet thereof.

In the present invention, this crosslinked plastic film or sheet has a heat shrinkage temperature of about 80 to 200°C, particularly 90°C.
~180℃, but the heat shrinkage rate is approximately 20~80%,
Preferably it is about 30 to 70%, and the degree of crosslinking of the polymer forming the crosslinked plastic film or sheet is about 2%, expressed as the gel fraction described below.
It is preferably 0 to 90%, particularly 25 to 80%.

The above gel fraction means that the sample (crosslinked plastic film or sheet) is placed in xylene for about 10 hours.
The value obtained by melting the sample under reflux at a temperature of approximately 130°C and dividing the weight (Ag) of the sample that did not dissolve in xylene by the weight of the total sample used (B g) multiplied by 100. be.

Gel fraction = (A/B) -6, nylon-6,6) is formed into a film or sheet by extrusion molding, and then the film or sheet is
It is suitable if it is formed from a heat-shrinkable cross-linked plastic film or film that has been stretched at a high temperature of ~200° C. and then cooled in the stretched state.

Further, the adhesive N32 is used in a high temperature region (for example, a high temperature within a range of about 80 to 200°C) where the heat-shrinkable crosslinked plastic layer 31 exhibits the largest heat shrinkage force.
such that it can exhibit an adhesive strength expressed in shear strength (^STM olo02) in the range of about 0.005 to 0.05 kg/cl, preferably in the range of o,o°07 to 0.04 kg/-. , consisting of an adhesive layer containing an elastomer material as a main component.

As mentioned above, this adhesive N32 maintains adhesive strength at high temperatures, and at room temperature (around 20°C), it maintains adhesive strength of approximately 0.8
It is appropriate to use an adhesive that exhibits a shear strength of about 1.0 to 25 kg/d, particularly about 1.0 to 25 kg/d.

The adhesive layer 32 may be made of an olefin-based material such as polyisobutene rubber (IIR; butyl rubber), ethylene-propylene copolymer rubber (EPR), or ethylene-propylene-nonconjugated diene copolymer rubber (EPDM). Elastomer, polybutadiene rubber, polyisoprene rubber,
Other non-conjugated diene elastomers such as styrene-9-tadiene copolymer rubber, acrylonitrile-butadiene AiLl rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, acrylic rubber, epichlorohydrin rubber, chlorinated polyethylene rubber, fluorinated rubber, etc. Preferably it contains about 30 to 80% by weight, especially 35 to 70% by weight of elastomer component.

In addition to the elastomer component, the adhesive layer 32 contains other modifying polymers (modifying polymers) generally contained in adhesives, tackifiers, corrosion inhibitors, and inorganic fillers. may be blended. As a polymer for modification,
For example, olefin polymers such as polyethylene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, acrylate-ethylene copolymer, polypropylene, polybutene, polyvinyl chloride, polyamide,
Thermoplastic resins such as styrene polymers or liquid polymers can be mentioned, and examples of tackifiers (tackifiers) include rosin and rosin 10-derivatives, pinene resins, aliphatic hydrocarbon resins (Cs distillate), etc. , pentene, isoprene, ■, 3-pentadiene, etc.), aromatic hydrocarbon resins (Cs fraction, styrenes, indenes, etc. alone or copolymers)
, alicyclic hydrocarbon resin, coumaron resin, coumaron-indene resin, phenol resin, naphthenic oil, modified terpene, and the like. Examples of corrosion inhibitors include inorganic corrosion inhibitors such as metal chromates, metal phosphates, metal phosphites, metal borates, molybdates, and metal nitrites, aromatic carbon metal salts of acids,
Examples include aliphatic or aromatic compounds having multiple hydroxyl groups, organic corrosion inhibitors such as tannic acid, and inorganic fillers such as talc, charcoal, silica, alumina, mica, and carbon black. can be mentioned.

In the present invention, the adhesive layer 32 includes approximately 30 to 70% by weight of the aforementioned olefin elastomer, approximately 1 to 20% by weight of the modifying polymer, approximately 10 to 30% by weight of the tackifier, and approximately 5% by weight of the inorganic filler. ~20% by weight of a heat-adhesive adhesive composition, the adhesive strength (shear strength) at room temperature is about 1.0 kg/d or more, and the adhesive strength (shear strength) at high temperature about 0.0 at 80°C. O] kg
/cn1 or more, approximately 0.005 kg/c+a at 100℃
It is optimal because it is as high as above and does not drop suddenly even at temperatures higher than that.

In addition, if the elastomer component of the adhesive layer 32 becomes too small, the shear strength of the adhesive will increase if the heat shrinkage temperature of the heat-shrinkable coating material exceeds about 80°C, similar to a general hot-melt adhesive. This is not very appropriate because the elastomer component becomes extremely small, and if the elastomer component is too large, the adhesive force after being cooled to room temperature becomes small, which is not appropriate.

It should be noted that the tackifier is blended mainly for the purpose of imparting fluidity and tankability to the adhesive, and if the amount is too small, these properties will be lost, which is not desirable.

Further, in the present invention, it is preferable that the entire area of the adhesive layer 32 is formed of an adhesive layer having high shear strength at high temperatures as described above, but if necessary, a partial area thereof may be formed. It is formed with an adhesive layer that has high shear strength at high temperatures, and other flat parts may be formed with a normal hot melt type adhesive layer.

Typical hot-melt adhesive layers include thermoplastic resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, acrylnitrile-ethylene copolymer, polyvinyl chloride, polyester, polyamide, etc. 30 to 80% by weight %, asphalt (bitumen) 0 to 50% by weight, tackifier 10 to 20% by weight, inorganic filler 5 to 20% by weight, etc. It has excellent shear strength (5 to 30 kg/c+J), and is also heat-softening and heat-softening for small uneven surfaces to be coated.
This is appropriate because it allows for flexible responses.

Further, the heat-shrinkable sheet 1 with an adhesive layer 1 (see Fig. 3) used in the present invention is applied to the main pipe 23 around the neck 22 of the rising part 21 of the branch pipe 2 of the T-tube. It is sufficient if the size and shape allow close adhesion by causing thermal contraction.

In addition, the heat-shrinkable sheet 1 is provided with thermal adhesive that exhibits high shear strength at high temperatures on the entire back surface of the cross-linked plastic layer, although the composition and performance of the cross-linked plastic layer and adhesive layer that constitute the sheet 1 are not particularly limited. It is preferable that the adhesive layer is provided with a solid adhesive layer. Furthermore, if the heat shrinkage rate of the crosslinked plastic layer of the heat-shrinkable sheet 1 is greater than 30%, it will easily peel off during heating and cause shearing, and if the heat-shrinkage rate is too low, it will cause wrinkles. easy.

Next, a method of covering the T-tube 2 using the heat-shrinkable tape 3 and the heat-shrinkable sheet 1 with an adhesive layer described above will be explained in accordance with a preferred construction order with reference to the drawings.

First, prior to coating the T-tube 2, the surface of the T-tube 2 is treated. This surface treatment is carried out by polishing the surface of the T-tube 2 to a level of three types of scratches using a wire brush or a grinder to remove rust, grime, explosive welding particles, spatter, and the like. If there is grease, etc. attached, remove it using a non-oily solvent such as l-lichlorethylene, and if there is dirt, dust, etc. attached to the surface of the T-tube 2. Remove this with a rag. Then, the ends of the coating parts 24, 24.24, which are coated in advance on the main pipe 23 and branch pipe 21, respectively, in the T-tube 2 are chamfered to about 30 degrees or less from the horizontal.

Next, the heat-shrinkable sheet 1 with the adhesive layer is attached to the T-tube 2.
The main pipe 2 around the neck 22 of the rising part of the branch pipe 21
3, by heating with a gas burner 4 or the like to cause thermal contraction, they are adhered tightly as shown in FIG. For this close adhesion, the main pipe 23 around the neck 22 of the rising part of the branch pipe 21 of the T-shaped pipe 2 is pre-aligned at an angle of approximately 50 to 100 degrees.
The heat-shrinkable sheet 1 with an adhesive layer is placed around the entire circumference of the main pipe 23 around the neck 22 of the rising part of the branch pipe 21 of the preheated T-shaped pipe 2. You can rub it while heating it over low heat. Note that the above preheating may be completely omitted depending on the adhesive of the heat-shrinkable sheet 1.

Thereafter, a heat-shrinkable tape 3 having high shear strength at high temperatures is partially overlapped with the heat-shrinkable sheet 1 and wrapped around the main pipe 23 and branch pipes 21 while being heated and tensioned to cause heat shrinkage. By doing so, the main pipe 23 and branch pipe 21
In this case, it is preferable that the heat-shrinkable tape 3 be closely bonded to the branch pipe 21 before the main pipe 23.

In closely adhering the heat-shrinkable tape 3 to the branch pipe 21, first, the entire surface of the branch pipe 21 is preheated to about 50 to 100°C. However, this preheating may be completely omitted depending on the adhesive of the heat-shrinkable tape 3. Next, the heat-shrinkable tape 3 is supplied to the coating portion 24 of the branch pipe 21 while peeling off the release film, and is overlapped with the coating portion 24 by about 60 fl (width of the heat-shrinkable tape 3) to form a heat-shrinkable tape. The tip of the tape 3 is heated over low heat to bring it into close contact with the coating portion 24. The heat-shrinkable tape 3 is wrapped around the coating portion 24 approximately once. Next, the heat-shrinkable tape 3 is applied to the coating portion 24 of the branch pipe 21.
It is wrapped around the branch pipe 21 while heating it from the side toward the main pipe 23 to about 105 to 110°C. As shown in FIG.
Wrapping is performed by heating the outer surface immediately before wrapping. In this case, care must be taken because the heat-shrinkable tape 3 will curl if heated too much. Further, when wrapping the heat-shrinkable tape 3, the overlap should be approximately half of the width of the heat-shrinkable tape 3 as a guide. Moreover, the heat-shrinkable tape 3 wrapped around the branch pipe 21 is
If necessary, the surface thereof is heated over low heat to bring it into close contact with the branch pipe 21. Then, as shown in FIG. 4, the heat-shrinkable tape 3 is wrapped around the heat-shrinkable sheet 1 until it overlaps the heat-shrinkable sheet 1 by about 50 m, and the overlapped portion is heated over low heat to wrap the heat-shrinkable sheet 1. 17- Make sure it adheres well. Furthermore, as shown in FIG. 4, the ends of the heat-shrinkable tape 3 are cut at either shoulder of the heat-shrinkable sheet 1, and the cut ends are heated over low heat and pressed. (Shrinkable Sheet) 1).

In addition, when adhering the heat-shrinkable tape 3 to the main pipe 23, first, the entire surface of the main pipe 21 is preheated to about 50 to 100°C, as shown in FIG. However, this preheating may be completely omitted depending on the adhesive of the heat-shrinkable tape 3. Next, apply the heat-shrinkable tape 3 to the coated portion 24 of one of the main pipes 23 to a thickness of approximately 60 mm as in the case of the branch pipes 21.
After overlapping the seal, coat the other coating part 2.
4, as shown in FIG. The adhesive sheet 1 is wrapped sufficiently, and finally, the wrapping is completed by overlapping the other coating portion 24 about 60 times.

When the winding is completed, the heat-shrinkable tape 3 is cut 18- and the cut ends of the heat-shrinkable tape 3 are covered with heat-sealing tape 5, so that the color of the temperature-indicating paint on the sealing tape 5 changes. (approximately 200° C.) and press from time to time to ensure sufficient adhesion.

Thus, according to the present invention, a T-tube can be coated as shown in FIG.

Hereinafter, the adhesive N32 of the heat-shrinkable tape 3 used in the present invention will be described.
Test examples of preferred adhesives for forming T-tubes and examples of the method of covering T-tubes of the present invention will be shown together with comparative examples.

In addition, in the test example, the shear strength of the adhesive was determined by bonding two iron plates (125 mm x 25 Dragon Xi, 5++n) to each other by 12
After stacking the steel plates together and interposing an adhesive between the overlapped parts, the steel plates were heated to a bonding temperature of 130℃ for about 5 minutes, and the steel plates were simultaneously pulled in the direction of both ends using a universal testing machine.
The measurement was performed according to the measurement method of STM old 002.

Test Example An adhesive having the composition shown below was kneaded in a kneader at a temperature of 150 DEG C. for 5 minutes, and then rolled into an adhesive sheet having a thickness of 1.5 mm.

Butyl rubber 30% by weight Ethylene-propylene-nonconjugated diene copolymer 35% by weight Coumarone-indene resin 25% by weight Talc 10% by weight It is 0.014 kgloa, 0.029 kg/ci at 80°C, does not decrease rapidly even at 110°C, and is 1.15 kg/ci at 20°C.
It was d.

Example First, the adhesive sheet used in the above test example was made to a thickness of 1fi.
A heat-shrinkable sheet 1 formed by bonding to the entire surface of one side of a cross-linked plastic sheet (heat shrinkage rate: 20%, thickness: 2.
A T-shaped pipe 2 (main pipe 23 and branch pipe 2) whose surface was previously treated
The main pipe 23 around the neck 22 of the rising part of the branch pipe 21 (diameter of 1; 4 inches in each case) is heated with a gas burner 4 or the like to cause heat shrinkage, and is tightly bonded as shown in FIG. 3. I let it happen. For this close adhesion, the main pipe 23 around the neck 22 of the rising part of the branch pipe 21 of the T-tube 2 is preheated to about 80°C, and the preheated T-tube 2
The book Il around the neck 22 of the rising part of the branch pipe 21
The heat-shrinkable sheet 1 with an adhesive layer was placed around the entire circumference of ¥r23, and the sheet was rubbed while being heated over low heat.

Next, the entire surface of the branch pipe 21 is preheated to about 80° C., and an adhesive sheet with a thickness of 0.8 vs. having the same composition as the adhesive sheet used in the above test example is coated with a crosslinked plastic sheet (with a thickness of 0.8 VS). 7mm, gel fraction 60%, heat shrinkage rate 45%
, heat shrinkage temperature 105℃) after bonding to the entire surface of one side
The end of the heat-shrinkable tape 3 formed in the zero-length overlaps the coating part 24 of the branch pipe 21 by about 60 mm, and is heated over low heat to bring it into close contact with the coating part 24, and then the heat-shrinkable tape 3 is was wrapped around the branch pipe 21 from the side of the coating portion 24 of the branch pipe 21 toward the main pipe 23 while being heated to about 105 to 110°C with an overlap of about 3011 = 21-. Then, as shown in FIG. 4, the heat-shrinkable tape 3 is wound until it overlaps the heat-shrinkable sheet 1 by about 50 nm, and the overlapped portion is heated over low heat to wrap the heat-shrinkable sheet 1. was placed in close contact with the Furthermore, as shown in FIG. 4, the end of the heat-shrinkable tape 3 is cut at the left shoulder of the heat-shrinkable sheet 1, and the cut end is heated and pressed over low heat. It was brought into close contact with the heat-shrinkable sheet 1.

Thereafter, as shown in FIG. 4, the entire surface of the main pipe 21 is preheated to about 80° C., and the heat-shrinkable tape 3 is applied to the coating portion 24 on the left side of the main pipe 23 in the same manner as in the case of the branch pipe 21. about 6 to
After 0m overlap, coating section 2 on the right
4, as shown in FIG. The material was sufficiently wrapped around the sex sheet 1, and finally, the right coating portion 24 was overlumped by about 60 fins, and the wrapping was completed. After the winding is completed 22-, the heat-shrinkable tape 3 is cut, the cut ends of the heat-shrinkable tape 3 are covered with heat-sealing tape 5, and the sealing tape 5 is sealed until the color of the temperature-indicating paint changes. It was sufficiently heated (approximately 200° C.) and pressed occasionally to achieve sufficient adhesion.

As a result, the heat-shrinkable tape did not cause any slippage, peeling, or voids, and a good coating layer was formed as shown in FIG. 6.

Comparative Example Instead of the heat-shrinkable tape used in the example, a heat-shrinkable sheet (width 450 m, length 5
20%, thickness of cross-linked plastic layer 1. Otm, the thickness of the adhesive layer is 1.51 m>, and the heat-shrinkable sheet is
Branch pipe 21 and main pipe 23 of the T-shaped pipe, respectively, similar to the example
An attempt was made to form a cylindrical sleeve by placing it around the T-tube and heat sealing tape to form a cylindrical sleeve, heat the sleeve to about 110°C with the flame of a gas burner, and heat shrink it to tightly bond it around the T-tube. Due to the rigidity of the sleeve, it was not possible to tightly bond the sleeve 23 around the T-tube, and the width of the heat seal tape had to be relatively wide compared to the total length of the sleeve. No heat shrinkage
Therefore, there was an inconvenience that the sleeve could not be tightly joined around the T-shaped pipe, and coating construction could not be performed.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an example of the heat-shrinkable tape used in the present invention, Fig. 2 is an enlarged partial sectional view thereof, and Fig. 3 shows how a branch pipe of a T-shaped pipe is coated with heat-shrinkable tape. A perspective view, FIG. 4 is a perspective view showing how a branch pipe of a T-shaped pipe is covered with heat-shrinkable tape, and FIG. 5 is a perspective view showing how the main pipe of a T-shaped pipe is covered with heat-shrinkable tape. FIG. 6 is a perspective view showing how the T-tube is covered with a heat-shrinkable tape. 1... Heat-shrinkable sheet with adhesive layer 2... T-shaped pipe 21... Branch pipe 22... Neck 23... Main pipe 3... Heat-shrinkable tape IQ':

Claims (1)

[Claims] In a method of covering a T-shaped pipe with a heat-shrinkable material, the T-shaped pipe has branch pipes branching from the main pipe in a T-shape. After closely adhering to the main pipe around the neck by heating to cause heat shrinkage, a heat-adhesive adhesive layer is provided on one side of the heat-shrinkable crosslinked plastic layer, and the adhesive layer is The entire area or a partial area is approximately 0.0 O5 to 0 at the temperature at which the crosslinked plastic layer exhibits the greatest heat shrinkage force.
, shear strength within the range of 05 kg/cat (457M
A heat-shrinkable tape formed of an adhesive layer containing an elastomer material as a main component and capable of exhibiting the adhesive force expressed by 1. A method for covering a T-shaped pipe, which comprises wrapping the pipe under tension while heating it to cause thermal contraction, thereby tightly adhering the main pipe and branch pipes.