JP2000112275A - Two-layered thin-walled cylindrical pipe and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a two-layered thin-walled cylindrical pipe which has high rigidity and the excellent uniformity of a temperature distribution and may be formed to a smaller thickness and smaller size by providing this thin cylindrical pipe with an outer peripheral layer consisting of a high-thermal conductivity material, such as aluminum alloy, and an inner peripheral layer which is rolling-joined to the inner periphery of this outer peripheral layer and consists of a high-rigidity material, such as a stainless steel alloy. SOLUTION: The fixing roller having the thin-walled cylindrical pipe 1 having the two- layered structure has the inner peripheral layer 1b and outer peripheral layer 1a consisting of materials varying in the coefficient of thermal expansion and a release layer formed on the outer periphery of the outer peripheral layer 1a. The outer peripheral layer 1a consists of the high-thermal conductivity material, such as the aluminum alloy, and the inner peripheral layer 1b consists of the high-rigidity material, such as the stainless steel alloy. The inner peripheral layer 1b is rolling-joined by cold drawing to the inner periphery of the outer peripheral layer 1a. The material of the inner peripheral layer 1b may be iron or iron compound in place of the stainless steel alloy. The outer peripheral surface of the thin cylindrical pipe 1 is coated with a release layer 2a consisting of a fluororesin, etc., and such thin cylindrical pipe may be used as a fixing roller. The film thickness of this release layer 2a is specified to 10 to 30 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-layer thin cylindrical tube made of materials having different linear expansion coefficients, and more particularly to a two-layer structure used for an electrophotographic photosensitive member, a developing sleeve, a fixing roller, etc. used in an electrophotographic apparatus. The present invention relates to a thin cylindrical tube and a method for manufacturing the same.

[0002]

2. Description of the Related Art For example, a fixing roller used in an electrophotographic copying machine, a laser beam printer, or the like is made of a thin cylindrical tube 1 made of an aluminum alloy having an outer diameter φd as shown in FIG. One coated with a release layer 2a is used.

In this fixing roller, a heat generator such as a halogen heater is inserted inside the roller for fixing the toner transferred to the copy paper, and the toner is fixed on the transfer paper by radiant heat from inside and pressure by a pressure roller. Let it. Therefore, the fixing roller base is required to have good heat conduction and high rigidity.

Further, in recent years, demands for energy saving and cost reduction have led to a demand for a thinner and smaller diameter of the fixing roller base.

However, in the thin-walled cylindrical tube made of this aluminum alloy, the wall thickness is t = 0.8 mm, which is a critical point in the process, and it is difficult to reduce the wall thickness due to the rigidity of the base. Therefore, the rising time of the fixing roller at this thickness is limited to about 30 sec.

In view of the above, it has been desired to reduce the wall thickness in order to have good thermal conductivity and high rigidity, and to reduce the diameter and the rise time in recent years.

[0007]

However, in order to achieve this reduction in thickness, conventional aluminum alloys have been developed into iron-based and stainless steel-based cores. It does not meet the requirements for low cost from workability. Further, since the thermal conductivity is lower than that of an aluminum alloy, the uniformity of temperature distribution, which is a function of the fixing roller, is not sufficiently developed as an alternative material.

Accordingly, an object of the present invention is to provide a two-layer thin cylindrical tube having high rigidity, excellent uniformity of temperature distribution, and capable of thinning and reducing the diameter, and a method of manufacturing the same.

[0009]

In order to achieve the above object, a two-layered thin-walled cylindrical tube according to claim 1 is a two-layered thin-walled cylindrical tube made of materials having different coefficients of thermal expansion. And an inner peripheral layer made of a highly rigid material such as a stainless alloy, which is rolled and joined to the inner periphery of the outer peripheral layer.
With this configuration, a uniform temperature distribution can be obtained by the outer peripheral layer, and the rigidity of the core metal can be improved by the inner peripheral layer, and the thickness can be reduced.

[0010] The two-layered thin-walled cylindrical tube of claim 2 is
2. The two-layered thin-walled cylindrical tube according to claim 1, wherein a displacement preventing means for preventing the outer periphery of the inner peripheral layer and the inner periphery of the outer peripheral layer from shifting in the axial direction due to thermal stress is provided on the outer periphery of the inner peripheral layer. And at least one of the inner periphery of the outer peripheral layer. With this configuration, it is possible to prevent the inner peripheral layer and the outer peripheral layer from shifting in the axial direction due to thermal stress.

Further, the thin cylindrical tube having a two-layer structure according to claim 3 is
3. The thin-walled cylindrical tube having a two-layer structure according to claim 2, wherein the deviation preventing means is an uneven surface formed on an outer peripheral surface of the inner peripheral layer. With this configuration, the inner circumferential surface of the outer circumferential layer enters the uneven surface of the outer circumferential surface of the inner circumferential layer, so that the bonding strength can be improved, and the inner circumferential layer and the outer circumferential layer are prevented from shifting in the axial direction due to thermal stress. can do.

Further, the thin-walled cylindrical tube having a two-layer structure according to claim 4 is
The thin-walled cylindrical tube having a two-layer structure according to claim 2, wherein the displacement preventing means is a throttle formed in an opening at both ends of the thin-walled cylindrical tube in an inner diameter direction. With this configuration, it is possible to prevent axial displacement by the throttle portion.

[0013] The two-layered thin-walled cylindrical tube of claim 5 is
The thin-walled cylindrical tube having a two-layer structure according to claim 4, wherein the throttle portion is formed in a key shape that covers at least a part of an end surface and an inner peripheral surface of the inner peripheral layer. In this configuration, the key shape can prevent the shaft from being displaced during the processing step and when using the product.

The thin-walled cylindrical tube having a two-layer structure according to claim 6 is
2. The thin-walled cylindrical tube having a two-layer structure according to claim 1, wherein the displacement preventing means is formed on an outer peripheral surface of the inner peripheral layer.
It is characterized by being an i-alloy-based plating layer. In this configuration, the inner layer and the outer layer can be bonded to each other by the plated layer to improve the bonding strength between the metal layers, and the axial displacement can be prevented.

Further, the thin cylindrical tube having a two-layer structure according to claim 7 is
The two-layer thin cylindrical tube according to claim 3, wherein the uneven surface is formed by sandblasting. In this configuration, the joining strength can be improved by the sandblasting process, and thereby the axial displacement can be prevented.

According to a second aspect of the present invention, there is provided a method for manufacturing a two-layer thin cylindrical tube made of materials having different coefficients of thermal expansion. A blast material such as alumina-based glass beads is discharged onto the outer peripheral surface of the layer to roughen the surface layer by sandblasting, and then the surface layer is roughened, and then a high thermal conductive material such as an aluminum alloy is cold drawn. The inner peripheral layer is roll-bonded to the inner periphery of the outer peripheral layer made of With this configuration, the joining strength can be improved by sandblasting, and thereby a two-layer thin cylindrical tube that can prevent axial misalignment can be manufactured.

According to a ninth aspect of the present invention, there is provided a method for manufacturing a two-layered thin cylindrical tube made of materials having different thermal expansion coefficients, wherein the outer periphery is made of a material having a high thermal conductivity such as an aluminum alloy. The inner peripheral layer made of a high-rigidity material such as a stainless alloy is roll-joined to the inner periphery of the layer, and thereafter, the end of the outer peripheral layer is subjected to drawing. With this configuration, it is possible to manufacture a two-layer thin-walled cylindrical tube in which axial displacement can be prevented by the throttle portion.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. In the following, common parts are denoted by the same reference numerals, and description thereof is omitted.

FIG. 7 is a sectional view showing a two-layer thin cylindrical tube according to the first embodiment of the present invention. A fixing roller having a thin-walled cylindrical tube 1 having a two-layer structure shown in FIG. 7 includes an inner peripheral layer 1b and an outer peripheral layer 1a made of materials having different thermal expansion coefficients, and an outer peripheral layer 1a.
And a release layer 2a formed on the outer periphery of the substrate.

The outer peripheral layer 1a is made of a high thermal conductivity material such as an aluminum alloy, and the inner peripheral layer 1b is made of a highly rigid material such as a stainless alloy. Then, the inner peripheral layer 1b is rolled and joined to the inner periphery of the outer peripheral layer 1a by cold drawing. The material of the inner peripheral layer 1b may be iron or an iron compound instead of the stainless steel alloy.

The release layer 2 made of fluororesin or the like is provided on the outer peripheral surface of the thin-walled cylindrical tube 1 having the two-layer structure manufactured as described above.
a is coated and can be used as a fixing roller.
The thickness of the release layer 2a is 10 to 30 μm.

The thin-walled cylindrical tube 1 having the two-layer structure shown in FIG. 7 has characteristics of an aluminum alloy, iron, and stainless steel. That is, it has high rigidity, excellent uniformity of temperature distribution, and can be made thinner and smaller in diameter.

Further, a thin-walled cylindrical tube 1 having a two-layer structure shown in FIG.
In the above, the core metal form of the thin-walled cylindrical tube 1 for the fixing roller can be easily and inexpensively formed, so that the rising time of the fixing roller can be shortened and the manufacturing cost can be reduced.

As shown in FIG. 8, in the case of a joining state of only rolling joining by cold drawing, there is a possibility that core metal deformation due to thermal stress may occur.

Specifically, in terms of production and product functions, the core metal for the fixing roller is subjected to baking of the fluororesin in the surface layer during the processing step, and heat is applied for fixing the toner when the product is used. Therefore, during the processing step, in the firing step of the fluororesin, the outer layer 1a and the inner layer 1b, which are the two-layer structure, are peeled off due to the difference in thermal expansion, resulting in misalignment. The difference causes an axis shift.

In order to solve such a problem, in the two-layer thin cylindrical tube 1 according to the second embodiment of the present invention, as shown in FIG. I do.

First, the method of forming the constricted portion 3 is shown in FIG.
(A) As shown in FIG.
Then, the thin cylindrical tube 1 composed of the stainless steel inner peripheral layer 1b rolled and joined to the inner periphery of the outer peripheral layer 1a as described above is chucked by a processing machine (not shown) and rotated.

Next, as shown in FIG. 4 (B), by moving the forming device 10 in the longitudinal direction while abutting on the outer peripheral surface of the outer peripheral layer 1a during rotation, the opening end surface becomes the thin cylindrical tube 1 It is formed in a tapered shape contracted at a fixed angle with respect to the rotation center axis 1c (see FIG. 3). Note that, in FIG.
1 is a spinning roller, 12 is a thrust bearing, 13 is a radial bearing, and 14 is a shank member.

Further, as shown in FIG. 4C, the outer peripheral surface of the thin-walled cylindrical tube 1 is cut using a diamond cutting tool 20 or the like. By this processing, a uniform outer peripheral surface can be obtained.

The outer peripheral surface of the thin-walled cylindrical pipe 1 whose outer diameter has been cut is subjected to sandblasting. This sandblasting is performed in order to improve the adhesion at the time of coating the release layer 2a which is a coating member made of a fluororesin or the like in the next step.
Subsequently, after the release layer 2a is subjected to electrostatic powder coating, baking is performed to perform a coating process.

Since the surface of the release layer 2a to be the coated surface layer 2 is roughened by firing, the surface is finished by tape polishing to obtain desired surface roughness and film thickness.

Through the above processing steps, a desired fixing roller is manufactured. However, the inner peripheral layer 1b of the thin cylindrical tube 1 according to the present invention is formed by the aperture shape 3a of the aperture portion 3 formed at the opening at both ends. It is possible to prevent the generation of the axial deviation d as shown in FIG. 8 due to the thermal stress applied during the processing step and when the product is used.

Next, one embodiment of the drawing process shown in FIGS. (Embodiment) The thin cylindrical tube 1 to be processed has an outer peripheral layer 1a.
Is made of A5052 aluminum alloy
1 × 380L × t2.0, and the inner peripheral layer 1b is made of SU
Φ3 by stainless steel material composed of S304 series equivalent material
It is a two-layer structure formed by 8 × 380 L × t0.5.

The drawing process of the openings at both ends is performed by a processing machine C
An NC lathe is used. The main processing conditions of this CNC lathe are a spindle rotation speed of 1500 rpm and a pushing amount of φ3.0 mm at the maximum. Under these processing conditions, taper processing was performed.

The outer peripheral surface of the thin cylindrical tube 1 is fixed to a spindle chuck of a CNC lathe as a processing machine, and the spindle is rotated under the above conditions. Thereafter, the forming apparatus 10 was moved in the direction of the opening end face while being in contact with the outer peripheral surface 1b, and the drawn shape 3a was formed by using a taper cycle in which the amount of pushing was gradually changed. The feed amount f at this time was 0.07 mm / rev.

The main dimensions of the spinning roller 11 of the molding apparatus 10 used at this time were an outer diameter φ150, and a nose at the tip was R2.0.

Next, with the thin-walled cylindrical tube 1 chucked, the spindle rotation speed was set to 4500 rpm, and the feed amount was set to 0.13.
The outer diameter was cut using a diamond tool 20 (see FIG. 4 (C)) at mm / rev. As a result, the surface roughness Rz is about 3 μm.

In the sand blasting, the average particle size is 50 μm.
(Nominal particle size # 180) alumina material with discharge pressure 2.5 ~
The surface is roughened at 4.0 kgf / cm ² . As a result, the surface roughness Rz is 9 to 12 μm, and the waveform is also random.

Next, a release layer 2a made of fluorine resin or the like
Was subjected to electrostatic powder coating and fired at 380 ° C. to form a film. The surface layer 2 formed after firing has a thickness of 20 to
The surface roughness is about 24 μm, and the surface roughness Rz is 2.5 to 3 μm.

Therefore, the desired surface roughness Rz ≦ 2 μm can be obtained by polishing the surface layer 2 with a tape, and the surface layer 2 can be used as a fixing roller.

Instead of performing such drawing, FIG.
As shown in (A), the end of the outer layer 1a is formed longer than the end of the inner layer 1b, and the end of the outer layer 1a is
End of the outer peripheral layer 1a so as to contact the end of the key 3
b may be bent.

Further, as shown in FIG.
The key 3b may be bent and formed so that the end of “a” contacts the end of the inner peripheral layer 1b to the inner peripheral surface.

Further, as shown in FIG. 1, by subjecting the outer peripheral surface of the inner peripheral layer 1b to sandblasting, unevenness of the outer peripheral surface of the inner peripheral layer 1b roughened during cold drawing is reduced. The joining strength is improved by the penetration of the aluminum alloy. In this sand blasting process, a blast material such as an alumina-based glass bead is discharged onto the outer peripheral surface of the stainless alloy as the inner peripheral layer 1b during cold drawing to roughen the surface layer surface. The surface roughness of the surface layer is 5 points in ten-point average roughness.
It is desirable that it is not less than μm, preferably 9 to 15 μm.

Further, as shown in FIG. 2, by subjecting the outer peripheral surface of the inner peripheral layer 1b or the inner peripheral surface of the outer peripheral layer 1a to an AL-Si alloy plating treatment, metal-to-metal bonding is achieved and the bonding strength is further improved. Therefore, it is possible to prevent the axial deviation d (see FIG. 8) due to the thermal stress when using the preliminary product during the above-mentioned processing steps. This plating treatment is desirably formed to a thickness of 5 μm or more, preferably 10 to 60 μm, on the outer peripheral surface of the stainless alloy which is the inner peripheral layer 1b at the time of cold drawing.

The above-described thin-walled cylindrical tube 1 having a two-layer structure according to the present invention.
Can be easily applied to a thin-walled cylindrical tube 1 having a drum-shaped T outer diameter in the longitudinal direction as shown in FIG. The amount of drum in this case depends on the product performance, but is generally about 0.08 mm.

As described above, in the fixing roller having the release layer 2a on the outer peripheral surface of the thin-walled cylindrical tube 1, the thin-walled cylindrical tube 1 includes the outer peripheral layer 1a made of a material having a high thermal conductivity such as an aluminum alloy and the outer peripheral layer 1a. Inner peripheral layer 1b made of a high-rigidity material such as a stainless alloy and roll-bonded to the inner periphery of layer 1a
In the case of being constituted by a two-layer structure having the following, a uniform temperature distribution is obtained by the outer peripheral layer 1a,
The inner peripheral layer 1b improves the rigidity of the core metal and enables a reduction in thickness.

A displacement preventing means for preventing the outer periphery of the inner peripheral layer 1b and the inner periphery of the outer peripheral layer 1a from shifting in the axial direction due to thermal stress is provided.
a, the inner layer 1b and the outer layer 1a are prevented from being displaced in the axial direction due to the sintering process of the fluororesin or the thermal stress during use of the product. can do.

Further, the displacement preventing means is provided in the inner peripheral layer 1.
b, the inner peripheral surface of the outer peripheral layer 1a enters the outer peripheral surface of the inner peripheral layer 1b, so that the bonding strength can be improved. It is possible to prevent the inner peripheral layer 1b and the outer peripheral layer 1a from shifting in the axial direction due to thermal stress during use of the product.

In the case where there is a constricted portion formed in the opening at both ends of the thin-walled cylindrical tube 1 in the inner diameter direction, the displacement preventing means prevents the shaft from being displaced in the processing step and in using the product by the constricted portion. can do.

Further, when the constricted portion is formed in a key shape that covers at least a part of the end surface and the inner peripheral surface of the inner peripheral layer 1b, the constricted portion is formed by the key shape during a processing step and during use of a product. Axis displacement can be prevented.

Further, the displacement preventing means is provided in the inner peripheral layer 1.
In the case of an AL-Si alloy plating layer formed on the outer peripheral surface of b, the plating layer can improve the bonding strength by bonding the inner peripheral layer 1b and the outer peripheral layer 1a to each other by intermetallic bonding.
It is possible to prevent the shaft from being displaced during the processing step and when using the product.

When the uneven surface is formed by sand blasting, the joining strength can be improved by sand blasting, and the shaft can be prevented from being displaced during the processing step and when using the product.

Further, a release layer 2 a is formed on the outer peripheral surface of the thin cylindrical tube 1.
In the method for manufacturing a fixing roller having the above, a blast material such as an alumina-based glass bead is discharged onto the outer peripheral surface of the stainless alloy as the inner peripheral layer 1b of the thin-walled cylindrical tube 1 to perform a sand blasting treatment to roughen the surface layer surface. Thus, when the surface layer is roughened, and then the inner peripheral layer 1b is rolled and joined to the inner periphery of the outer layer 1a made of an aluminum alloy by cold drawing, the joining strength can be improved by sandblasting. In addition, it is possible to manufacture a fixing roller that can prevent axial misalignment during a processing step and during use of a product.

Further, a release layer 2 a is formed on the outer peripheral surface of the thin cylindrical tube 1.
In the method for manufacturing a fixing roller having the above, the thin cylindrical tube 1 is formed by rolling and joining an inner peripheral layer 1b made of a stainless steel alloy to an inner periphery of an outer peripheral layer 1a made of an aluminum alloy, and thereafter, an outer peripheral surface of the thin cylindrical tube 1 is formed. In the case where the drawing process is performed by contacting the spinning roller with the roller, a fixing roller can be manufactured that can prevent the shaft from being misaligned during the working process and when using the product by the drawing portion.

The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the gist of the present invention.

[0056]

As described above, according to the two-layer thin cylindrical tube of the first aspect, a uniform temperature distribution can be obtained by the outer peripheral layer, and the rigidity of the core metal can be improved by the inner peripheral layer to reduce the thickness. This has the effect of providing a two-layered thin-walled cylindrical tube capable of performing the above.

According to the two-layered thin cylindrical tube of the second aspect, it is possible to prevent the inner peripheral layer and the outer peripheral layer from shifting in the axial direction due to thermal stress.

According to the thin-walled cylindrical tube having the two-layer structure of the third aspect, the inner peripheral surface of the outer peripheral layer enters the uneven surface of the outer peripheral surface of the inner peripheral layer, so that the bonding strength can be improved.
It is possible to prevent the inner peripheral layer and the outer peripheral layer from shifting in the axial direction.

Further, according to the thin-walled cylindrical tube having a two-layer structure according to the fourth aspect, axial displacement can be prevented by the throttle portion.

According to the double-layered thin cylindrical tube of the fifth aspect, the key shape can prevent the shaft from being displaced during the processing step and when the product is used.

Further, according to the thin-layer cylindrical tube having a two-layer structure, the inner layer and the outer layer can be bonded to each other by the plating layer to improve the bonding strength, and the axial displacement can be prevented. it can.

Further, according to the thin-layer cylindrical tube having a two-layer structure according to the seventh aspect, the joining strength can be improved by sandblasting, whereby the axial displacement can be prevented.

According to the method for manufacturing a thin-walled cylindrical tube having a two-layer structure according to the eighth aspect, the joining strength can be improved by sandblasting, and thereby a double-layered thin-walled cylindrical tube can be prevented from being misaligned. Can be manufactured.

According to the method for manufacturing a thin-walled cylindrical tube having a two-layer structure according to the ninth aspect, it is possible to manufacture a thin-walled cylindrical tube having a two-layer structure capable of preventing axial misalignment due to the constricted portion.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a fourth embodiment of a thin-walled cylindrical tube having a two-layer structure according to the present invention.

FIG. 2 is a sectional view showing a fifth embodiment of a thin-walled cylindrical tube having a two-layer structure according to the present invention.

FIG. 3 is a sectional view showing a second embodiment of a two-layer thin cylindrical tube of the present invention.

FIG. 4 is a partial cross-sectional view showing a method for manufacturing a two-layer thin cylindrical tube of a second embodiment.

FIG. 5 is a sectional view showing a third embodiment of a thin-walled cylindrical tube having a two-layer structure according to the present invention.

FIG. 6 is a cross-sectional view showing a conventional thin cylindrical tube.

FIG. 7 is a cross-sectional view showing a first embodiment of a two-layer thin cylindrical tube of the present invention.

FIG. 8 is a cross-sectional view showing an axial displacement of a two-layer thin cylindrical tube.

FIG. 9 is a sectional view showing a fixing roller to which the present invention can be applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thin-walled cylindrical tube 1a Outer layer 1b Inner-layer 1c Rotation center axis of thin-walled cylindrical tube 2 Surface layer 2a Release layer 3 Restricted portion 3a Restricted shape 3b Key shape 10 Molding device 20 Diamond tool d Axis shift

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // B23K 103: 20 F term (reference) 2H033 AA03 BB13 BB26 2H035 CB02 2H068 AA52 AA54 AA59 CA32 CA44 EA07 2H077 AD02 AD06 AD14 FA03 FA26 4E067 AA03 AA05 BD01 BD02 DA06 DA09 EA04 EC06

Claims (9)

[Claims] 1. A two-layer thin-walled cylindrical tube made of a material having a different coefficient of thermal expansion, wherein an outer peripheral layer made of a material having a high thermal conductivity such as an aluminum alloy, and a stainless steel alloy which is rolled and joined to the inner periphery of the outer peripheral layer A thin-walled cylindrical tube having a two-layer structure. 2. A displacement preventing means for preventing the outer periphery of the inner peripheral layer and the inner periphery of the outer peripheral layer from being displaced in the axial direction due to a thermal stress is provided between the outer periphery of the inner peripheral layer and the inner periphery of the outer peripheral layer. The thin-walled cylindrical tube having a two-layer structure according to claim 1, wherein the thin-walled cylindrical tube is provided on at least one of them. 3. The two-layer thin-walled cylindrical tube according to claim 2, wherein the displacement preventing means is an uneven surface formed on an outer peripheral surface of the inner peripheral layer. 4. The thin-walled cylindrical tube according to claim 2, wherein the displacement preventing means is a narrowed portion formed at an opening at both ends of the thin-walled cylindrical tube in an inner diameter direction. 5. The thin cylinder having a two-layer structure according to claim 4, wherein the narrowed portion is formed in a key shape that covers at least a part of an end surface and an inner peripheral surface of the inner peripheral layer. tube. 6. The two-layer thin cylindrical tube according to claim 1, wherein the displacement preventing means is an AL-Si alloy-based plating layer formed on an outer peripheral surface of the inner peripheral layer. 7. The method according to claim 3, wherein the uneven surface is formed by sandblasting.
Layered thin cylindrical tube. 8. A method for manufacturing a thin-walled cylindrical tube having a two-layer structure made of materials having different coefficients of thermal expansion, wherein a blast material such as alumina-based glass beads is discharged onto an outer peripheral surface of an inner peripheral layer made of a highly rigid material such as a stainless alloy. The surface layer is roughened by sand blasting to roughen the surface layer, and then the inner layer is roll-bonded to the inner layer of the outer layer made of a high heat conductive material such as an aluminum alloy by cold drawing. A method for manufacturing a two-layer thin cylindrical tube. 9. A method for manufacturing a thin-walled cylindrical tube having a two-layer structure made of materials having different coefficients of thermal expansion, wherein an inner periphery of an outer layer made of a material having a high thermal conductivity such as an aluminum alloy is made of an inner periphery made of a highly rigid material such as a stainless alloy. A method for manufacturing a thin-walled cylindrical tube having a two-layer structure, comprising rolling and joining a peripheral layer, and thereafter drawing an end of the peripheral layer.