JPH07195515A - Heat insulating pipe member and production thereof - Google Patents

Abstract

PURPOSE:To provide a heat insulating pipe member excellent in heat insulating properties and capable of shortening the time required in vacuum exhaustion. CONSTITUTION:A heat insulating pipe member is obtained by winding a strip like heat insulating material around the outer periphery of a pipe member 2 in a lapped state to cover the outer peripheral surface of the pipe member 2 with the lap-winding layer of the strip like heat insulating material. The strip like heat insulating material is composed of stainless steel foil 4 having a large number of projections 4a distributed and formed on one surface thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating pipe used as an inner pipe (inner container) of a vacuum heat insulating double pipe, a vacuum heat insulating double container and the like, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Insulation pipes are used in various heat insulation pipes. For example, vacuum heat insulation double piping is used for liquid transportation pipes that transport ultra-low temperature fluids such as liquid nitrogen,
A heat insulating pipe is used as the inner pipe of the vacuum heat insulating double pipe. This type of adiabatic tube usually has a structure as shown in FIG.
On the outer periphery of the tubular body 33, alternate multilayer winding layers (10 to 10) of strip-shaped aluminum foil 31 and dexter paper (asbestos paper) 32 are provided.
It is constructed by providing about 30 layers) and is generally manufactured as follows. That is, first, the aluminum foil 31 and the dexter paper 32 are combined to form a two-layer body, which is wound around the outer circumference of the tube body 33.
It is manufactured by coating the outer peripheral surface of the above in multiple layers with a lap winding layer. Thermal insulation tube (inner tube) obtained in this way
The outermost layer is covered with an outer tube 34 with a space left between them, and in this state, a high vacuum is drawn between the outer tube 34 and the inner tube to produce a vacuum adiabatic double pipe.

[0003]

However, since the aluminum foil 31 and the dexter paper 32 are overlapped and wound in a state of surface contact with each other, there is a problem that the heat transfer amount is large and the heat insulating property is poor as a heat insulating material. is there. Moreover, since the above-mentioned dexter paper 32 is rich in water absorption,
When the heat insulating tube is manufactured in a high humidity atmosphere, the dexter paper 32 absorbs moisture in the air during the winding work to be in a high water content state. For this reason, in the process of manufacturing a vacuum heat insulating double pipe using the heat insulating pipe body, if the inner and outer pipes are evacuated, the moisture becomes a resistance of the vacuum evacuation, which causes a problem that it takes a long time for the vacuum evacuation. .

The present invention has been made in view of the above circumstances, and an object thereof is to provide a heat insulating tube having excellent heat insulating properties and capable of shortening the time required for evacuation, and a method for producing the same.

[0005]

In order to achieve the above object, the present invention is to wrap a strip-shaped heat insulating material around the outer circumference of a tube body and coat the outer peripheral surface of the tube body with a wrapping layer of the band-shaped heat insulating material. In the heat-insulating pipe body, the heat insulating pipe body made of a strip-shaped metal foil in which the strip-shaped heat insulating material has a large number of fine convex portions formed on one surface is defined as the first gist, and a large number of fine convex portions are formed on one surface. A second gist of the present invention is a method for producing a heat insulating pipe body in which the formed strip-shaped metal foil is wound around the outer periphery of the pipe body and the outer peripheral surface of the pipe body is covered with a lap winding layer of a band-shaped heat insulating material.

[0006]

That is, in the heat insulating tube of the present invention, the band-shaped heat insulating material used for the heat-insulating tube is composed of a band-shaped metal foil having a large number of minute convex portions distributed and formed on one surface thereof. In the layers, the two strip-shaped metal foils that are overlapped and wound are partially in contact with each other by using the minute convex portion formed on one of the strip-shaped metal foils as a contact portion. Therefore, the contact area between the overlapping strip-shaped metal foils is very small, the amount of heat transfer is small, and the heat insulating property is excellent.
Moreover, since it does not use the conventionally used highly water-absorbing dexter paper, it absorbs less water even when installed in a high-humidity atmosphere, so that vacuum exhaust can be performed in a short time. Become. In addition, between the winding layers of the strip-shaped metal foil, the portions without the fine protrusions become voids, so that the voids serve as air flow paths during vacuum exhaust, and vacuum exhaust can be efficiently performed. Further, according to the manufacturing method of the present invention, such a heat insulating tube can be easily manufactured.

Next, the present invention will be described in detail.

The heat insulating pipe body of the present invention is obtained by using the pipe body and the strip-shaped metal foil wound around the pipe body.

As the above-mentioned tubular body, various tubular products such as metal pipes, synthetic resin pipes, synthetic resin pipes whose surface is vapor-deposited or plated with metal are used.

The strip-shaped metal foil wound around the tubular body is not particularly limited, and various metal foils can be used. The thickness of these metal foils is 5 to 300.
μm, preferably 5 to 100 μm, more preferably 5 to
It is set to 30 μm. Among the above metal foils, in particular,
The use of a metal foil having a high melting temperature and good radiation efficiency, such as stainless steel foil, copper foil or nickel foil, gives good results.

As shown in FIG. 1 and FIG. 2 which is an enlarged view of a partial cross section of the strip-shaped metal foil, a large number of minute projections 4a are distributed and formed on one surface thereof. The minute convex portion 4a
As a method of forming the sandblasting method, a sandblasting method in which particles of silica sand or the like are sprayed on one surface of the strip-shaped metal foil 4 to form minute convex portions 4a in a satin-like distribution on the one surface, and a large number of small convex portions are formed on the surface as shown in FIG. A method of regularly forming the minute convex portions 4a on one surface by passing the strip-shaped metal foil 4 between the rotating roller 37 in which the portions 37a are formed and distributed and the rubber roller 38 having a flat surface is known. can give. In the case of the sandblast method, a rubber plate may be used as the base of the strip-shaped metal foil 4. The height of the minute convex portions 4a of the strip-shaped metal foil 4 thus obtained is ~ μm, and preferably,
Is ~ μm.

In the present invention, the above raw materials are used to manufacture, for example, a heat insulating pipe by an apparatus as shown in FIG. 4 or 8.
That is, in the method of FIG. 4, first, the mandrel 1 connected to a driving device such as the motor 16 and rotatably provided.
1. A tubular body 2 is externally fitted to 1 and a plurality of rotatably wound belt-shaped metal foils 4 having a plurality of minute convex portions 4a formed on its inner surface are distributed along one side of the tubular body 2. Na reel 1
Fix 2 and 13. At this time, the direction in which the strip-shaped metal foil 4 is pulled out from the reels 12 and 13 is a direction perpendicular to the tube body 2. The reels 12 and 13 are reel support bases 2.
The reel supports 20 and 21 are rotatably fitted around the outer circumferences of the reels 0 and 21, and brake claws (which are hidden and invisible) are provided on the outer circumferences of the reel supports 20 and 21. A pressure is applied to the peripheral surface to exert a braking action, which serves as resistance when the strip-shaped metal foil 4 is pulled out. In addition, the strip-shaped metal foil 4 wound around the reels 12 and 13 is the tubular body 2.
It is set so that the ends overlap little by little when wound around. In addition, 14 and 15 are shaft bodies to which the reel supporting bases 20 and 21 are attached, and 16a is a mandrel 1
1, the output shaft of the motor 16 connected to the right end 11a of the shaft 1 through the connecting member 17, 18 and 19 are support bases for rotatably supporting the ends of the shafts 14 and 15, and 22 is the end of the mandrel 11. It is a support base that rotatably supports the unit.

The reels 12 and 13 arranged as described above
The strip-shaped metal foils 4 are pulled out from the respective ends, and the ends thereof are fixed to the outer peripheral surface of the tubular body 2 by welding or the like. After that, as shown in FIG. 5, the driving device 16 is operated to rotate the mandrel 11 to rotate the tube body 2, and the rotational force is used to wind the strip-shaped metal wound around the reels 12 and 13. The foil 4 is wound around the outer circumference of the tube body 2 at a right angle, and a desired number of turns is wound around the outer circumference of the tube body 2. Thereby, the top of the minute convex portion 4a integrally formed on the strip-shaped metal foil 4 is in contact with the outer peripheral surface 2a of the tubular body 2 and the outer peripheral surface of the wound strip-shaped metal foil 4, while the strip-shaped metal foil 4 is formed. A heat insulating layer of a desired winding layer wound around the outer periphery of the tubular body 2 (a band-shaped metal foil 4 wound in layers and the minute convex portions 4a formed between the respective winding layers).
And a heat insulating layer interspersed therewith). Next, a band 30 for preventing rewinding is wound around the outermost periphery of the strip-shaped metal foil 4 wound in multiple layers at predetermined intervals as shown in FIG. 6, and the locking portion 30a is laid down from the standing state. , The strip-shaped metal foil 4 is fixed. Then, the tube body 2 covered with the lap winding layer of the strip-shaped metal foil 4 is removed from the mandrel 11. In this way, the desired heat insulating tube is obtained. Such a heat insulating pipe is used as an inner pipe of a vacuum heat insulating double pipe as shown in FIG. 7, for example. In FIG. 7, reference numeral 2 is a tube in the heat insulating tube, and the tube 2 has a plurality of strip-shaped metal foils 4 wound around the outer peripheral surface 2a thereof. 4 and between the strip-shaped metal foils 4 are formed with a heat insulating layer in which the minute convex portions 4a are scattered. 3 is an outer pipe, 7 is an exhaust pipe used for vacuuming, and 8 is a filter attached to the exhaust pipe 7.

On the other hand, in the method shown in FIG.
The tubular body 2 is externally fitted to a mandrel 11 that is rotatably connected to a driving device such as 6 and the left annular body (left dummy annular body) 46 is in contact with the left end edge of the tubular body 2.
Is in contact with the right edge, the right annular body (right dummy annular body)
47 is externally fitted. A screw shaft 44 is arranged along one side of the tubular body 2. In this case, the screw shaft 44 is rotated by the rotation of the motor 16 via the belt 49. Then, the reel shaft 4 is attached to the screw shaft 44.
3 is attached so that it can be moved back and forth by a screw mechanism. More specifically, a guide arm portion 48 provided with a sliding hole (hidden and invisible) is projectingly provided on the reel support base 43, and both supports for rotatably supporting the end portion of the screw shaft 44. The guide rod 45 is supported by the base 40, and the guide rod 45 is inserted into the sliding hole, whereby the reel support base 43 is prevented from being swung around the screw shaft 44.
The rotation of the screw shaft 44 causes the reel support base 43 to move to the screw shaft 4.
It is designed to move along with 4. Then, the reel 42 around which the strip-shaped metal foil 4 having a large number of minute projections 4a formed on its inner surface is wound is rotatably and detachably fitted onto the outer periphery of the reel support base 43. Further, on the outer periphery of the reel support base 43, as in the device of FIG. 4, a pawl for braking (hidden and invisible) is provided. A U-shaped support portion 41a is provided on the reel support base 43 so as to project therefrom.
The ridges are provided on both left and right sides of the flat plate-shaped guide portion 41b which is supported and fixed by the U-shaped support portion 41a.
The strip-shaped metal foil 4 pulled out from 2 acts as a guide to obliquely feed it toward the mandrel 11. As a result, the strip-shaped metal foil 4 is formed at the inclination angle of the guide portion 41b.
Is spirally wound around the outer periphery of the tubular body 2 and the left and right annular bodies 46, 47 fitted on the mandrel 11. In FIG. 8, 39 is a support stand that rotatably supports the end of the mandrel 11, and 50 and 51 are pulleys.

In the method of FIG. 8, the strip-shaped metal foil 4 is pulled out from the reel 42 arranged as described above, and its end is fixed to the outer peripheral surface of the left dummy annular body 46 on one end side by welding or the like. After that, as shown in FIG. 9, the motor 16 is operated to rotate the mandrel 11, thereby rotating the tubular body 2 and the left and right dummy annular bodies 46 and 47, and using this rotational force, the reel 42 is rotated. Band-shaped metal foil 4 wrapped around
Is spirally wound around the outer periphery of the left dummy annular body 46. In this case, the screw shaft 44 is rotated by the rotation of the motor 16 via the belt 49, whereby the reel support base 43 is rotated.
Moves to the right in the figure little by little, so the strip metal foil 4
Are wound while being slightly displaced in the axial direction of the mandrel 11 (shifted slightly to the right in the drawing). In this way, the strip-shaped metal foil 4 is wound from the outer peripheral surface of the left dummy annular body 46 to the outer peripheral surface of the tubular body 2 and further to the outer peripheral surface of the right dummy annular body 47. By the way, when the strip-shaped metal foil 4 is suddenly wound around the tubular body 2, the strip-shaped metallic foil 4 is wound at an angle with a slight shift, so that the number of windings is increased at the left end portion (winding start portion) of the tubular body 2. Will run out. The same applies to the right end portion (winding end portion) of the tubular body 2. Therefore, in the present invention, the dummy annular bodies 46 and 47 are provided on the left and right of the tubular body 2, and the winding start portion and the winding end portion of the strip-shaped metal foil 4 are positioned on the left and right dummy annular bodies 46 and 47. . Thereby, the strip-shaped metal foil 4 wound around the tube body 2 is
Any portion of the tube body 2 is a layer having the same number of turns. In this manner, the band-shaped metal foil 4 is fixed by winding the band 30 for preventing rewinding around the outer periphery of the band-shaped metal foil 4 wound around the entire tubular body 2 at predetermined intervals in the axial direction. Then, the tube body 2 covered with the lap winding layer of the strip-shaped metal foil 4 is removed from the mandrel 11. In this way, the desired heat insulating tube is obtained.

Next, the present invention will be explained based on examples.

[0017]

Example 1 As a strip-shaped metal foil, width 30 cm, thickness 15 μm
A number of minute convex portions were formed on one surface of the stainless steel foil of No. 1 by the sandblast method. Next, this stainless foil was placed on the device shown in FIG. 4 and wound (20 layers) on the outer circumference of a stainless inner tube to obtain the desired heat insulating tube. When a vacuum heat insulation double pipe as shown in FIG. 7 was constructed using this heat insulation pipe body, the heat insulation performance was improved and the vacuum evacuation time was remarkably shortened.

[0018]

Example 2 As a strip-shaped metal foil, width 30 cm, thickness 30 μm
A large number of minute convex portions were formed on one surface of the stainless foil of No. 3 by the method shown in FIG. Next, this stainless steel foil was placed on the device shown in FIG. 8 and wound (20 layers) around the outer circumference of the stainless steel inner tube. When the vacuum insulating double pipe shown in FIG. 7 was constructed using the obtained heat insulating pipe, excellent effects were obtained as in the case of the above-mentioned examples.

Further, in each of the above-mentioned examples, the minute convex portions 4a are formed between the winding layers of the strip-shaped metal foil 4 which is wound around the outer periphery of the tubular body 2 in a stacked manner.
However, the present invention is not limited to this, and the minute convex portions 4a may be scattered between arbitrary winding layers.

[0020]

As described above, the heat insulating pipe body of the present invention is
Since the band-shaped heat insulating material used for this purpose is composed of a band-shaped metal foil in which a large number of minute convex portions are distributed and formed on one surface, it is possible that the band-shaped heat-insulating material is wound in two layers between the winding layers of the band-shaped metal foil which is stacked and wound.
The two strip-shaped metal foils are partially in contact with each other by using the minute convex portion formed on one of the strip-shaped metal foils as a contact portion. Therefore, the contact area between the overlapping strip-shaped metal foils is very small, the amount of heat transfer is small, and the heat insulating property is excellent. Moreover, since it does not use the conventionally used highly water-absorbing dexter paper, it absorbs less water even when installed in a high-humidity atmosphere, so that vacuum exhaust can be performed in a short time. Become.
Moreover, since the portion without the fine protrusions is a void between the winding layers of the strip-shaped metal foil, the void serves as a flow path of air during vacuum exhaust, and the vacuum exhaust is efficiently performed. Further, according to the manufacturing method of the present invention, such a heat insulating tube can be easily manufactured.

[Brief description of drawings]

FIG. 1 is an explanatory view of a strip-shaped metal foil used for a heat insulating tube of the present invention.

FIG. 2 is an enlarged partial sectional view of the strip-shaped metal foil.

FIG. 3 is an explanatory diagram showing a method of forming minute protrusions on the strip-shaped metal foil.

FIG. 4 is a view of the apparatus for manufacturing the heat insulating pipe as viewed from above.

FIG. 5 is an explanatory diagram of a main part of the manufacturing apparatus.

FIG. 6 is a cross-sectional view showing a usage state of the band.

FIG. 7 is a partial cross-sectional view of a vacuum heat insulating double pipe using a heat insulating pipe of an example of the present invention.

FIG. 8 is a view of another example of the manufacturing apparatus for the heat insulating pipe as viewed from above.

FIG. 9 is an explanatory diagram of a main part of another example of the manufacturing apparatus.

FIG. 10 is a partial cross-sectional view of a conventional vacuum heat insulating double pipe.

[Explanation of symbols]

 2 Tubular body 4 Stainless steel foil 4a Small convex portion

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[Procedure amendment]

[Submission date] April 5, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

As shown in FIG. 1 and FIG. 2 which is an enlarged view of a partial cross section of the strip-shaped metal foil, a large number of minute projections 4a are distributed and formed on one surface thereof. The minute convex portion 4a
As a method of forming the sandblasting method, a sandblasting method in which particles of silica sand or the like are sprayed on one surface of the strip-shaped metal foil 4 to form minute convex portions 4a in a satin-like distribution on the one surface, and a large number of small convex portions are formed on the surface as shown in FIG. A method of regularly forming the minute convex portions 4a on one surface by passing the strip-shaped metal foil 4 between the rotating roller 37 in which the portions 37a are formed and distributed and the rubber roller 38 having a flat surface is known. can give. In the case of the sandblast method, a rubber plate may be used as the base of the strip-shaped metal foil 4. The height of the minute convex portions 4a of the strip-shaped metal foil 4 thus obtained is 50 to 500 μm, and preferably,
It is 200 to 350 μm.

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 5]

[Figure 6]

[Figure 9]

[Figure 4]

[Figure 7]

[Figure 8]

[Figure 10]

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Claims (2)

[Claims] 1. A heat-insulating pipe body, wherein a strip-shaped heat insulating material is wound around an outer circumference of the pipe body and the outer circumferential surface of the pipe body is covered with a lap winding layer of the band-shaped heat insulating material, wherein a large number of the band-like heat insulating materials are provided on one surface. 2. A heat insulating pipe body, which is made of a strip-shaped metal foil in which minute convex portions of are distributed and formed. 2. A strip-shaped metal foil in which a large number of minute convex portions are distributed and formed on one surface is lap-wound around the outer periphery of the pipe, and the outer peripheral surface of the pipe is covered with a lap winding layer of a strip-shaped heat insulating material. How to make a heat insulating pipe.