JP4336534B2 - Heat transfer tube with corrosion resistance - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an oil cooling pipe for automobiles and construction machines, an air conditioner for adjusting the temperature and humidity of a living space, and the like, and relates to a heat transfer pipe having corrosion resistance used in a corrosive environment. An object of the present invention is to obtain a heat transfer tube capable of efficient heat exchange with excellent heat dissipation characteristics.
[0002]
[Prior art]
Conventionally, as heat transfer tubes having corrosion resistance as described above, steel pipes subjected to anticorrosion plating such as galvanization and chromate coating, as disclosed in Japanese Patent Application Laid-Open No. 8-18884, and disclosed in Japanese Patent Application Laid-Open No. 10-315295, There is one in which a thermoplastic resin coating layer such as polyamide (PA), polypropylene (PP), polyethylene (PE) or the like is provided on the outer peripheral surface of a thin metal tube such as an aluminum tube by an extrusion molding method. The impact-absorbing power, water resistance, and chemical resistance of this resin coating layer prevent damage to the anti-corrosion plating layer and thin metal pipe due to stepping stones, and prevent oxidation of the thin metal pipe due to mud splashes and chemicals. , Increased the corrosion resistance of the heat transfer tube.
[0003]
[Problems to be solved by the invention]
However, the heat transfer tubes of the prior art as described above have a problem in terms of heat dissipation characteristics because the resin coating layer is formed thick in order to improve impact resistance and corrosion resistance, and circulate inside and outside the heat transfer tubes. It was difficult to efficiently exchange heat between the fluids. Therefore, in order to improve the heat dissipation characteristics, a long flat plate is spirally wound as in the invention described in JP-A-9-42573, the invention described in JP-A-9-136111, and the invention described in JP-A-11-325778. There is one in which a heat transfer tube is formed by winding in a shape and providing a fin member on the outer periphery of a thin metal tube. By this fin member, the heat dissipation characteristic of the heat transfer tube is enhanced, and the heat exchange efficiency between the fluid flowing inside the heat transfer tube and the fluid flowing outside can be improved. However, the anticorrosion plating layer on the surface of the small-diameter metal tube is easily damaged by stepping stones and the like, and there is a problem in corrosion resistance.
[0004]
The present invention is intended to solve the above-mentioned problems, and a thin metal tube is coated with a resin film layer having high impact resistance to enhance corrosion resistance and excellent in thermal conductivity on the outer periphery of the resin film layer. A heat exchanger tube made of metal is provided to improve heat dissipation characteristics and heat absorption characteristics, and a heat transfer tube excellent in heat exchange efficiency between a fluid flowing inside and a fluid flowing outside is obtained. Further, the heat transfer tube having excellent corrosion resistance and heat dissipation characteristics or heat absorption characteristics can be formed at a low cost with a simple structure.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the first invention is a thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and the outer periphery of the outermost layer of the resin coating layer. surface Formed with thin metal tube attached in close contact with It consists of a metal heat transfer body.
[0006]
Further, the second invention is a thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and an outer peripheral surface of the outermost layer of the resin coating layer. It was made of a metal strip wound in a spiral shape in close contact with It consists of a metal heat transfer body.
[0007]
Further, the third invention is a thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and an outer peripheral surface of the outermost layer of the resin coating layer. It was formed with a metal fin member that was closely attached to and wound in a spiral It consists of a metal heat transfer body.
[0008]
Further, the fourth invention is a thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and an outer peripheral surface of the outermost layer of the resin coating layer. It was made of a metal wire wound in a spiral shape in close contact with It consists of a metal heat transfer body.
[0009]
The thin metal tube may be provided with at least one anticorrosion plating layer on the outer surface and at least one resin coating layer on the outer peripheral surface of the anticorrosion plating layer.
[0010]
The heat transfer body may be provided with at least one anticorrosion plating layer on the outer surface.
[0011]
The heat transfer body may be formed by spirally winding resin-made outer peripheral fins on the outer peripheral surface.
[0012]
Moreover, the resin coating layer and / or the resin-made outer peripheral fins may contain metal or glass particles and / or fibers having higher thermal conductivity than the resin material.
[0013]
The resin coating layer and / or the resin-made outer peripheral fins may contain carbon nanofibers.
[0014]
Carbon nanofibers may be contained in a content of more than 5 wt% and less than 30 wt%.
[0015]
Further, the fin member and / or the outer peripheral fin may be provided with a turbulent flow means including any one of a pin, a protrusion, a strip-shaped plate material, an unevenness, a through hole, or a combination thereof on the outer peripheral surface.
[0016]
Two resin coating layers may be disposed on the outer peripheral surface of the thin metal tube.
[0017]
[Action]
Since the present invention is configured as described above, the resin coating layer provided on the outer peripheral surface of a small-diameter metal tube such as a steel tube or an aluminum tube is made of PE, PP, PA, etc. by an extrusion method or other methods. Any one kind of resin may be used to form a single layer, or two or more kinds of resins may be used to form a plurality of layers. Even if only one resin coating layer is used, excellent impact resistance can be obtained, and the number of steps for providing the resin coating layer can be reduced.
[0018]
In the case of multiple layers, for example, a PA layer having excellent adhesion to metal is disposed on the outer peripheral surface of a thin metal tube, and a PP layer having excellent water resistance and chemical resistance is provided on the outer peripheral surface of this PA resin coating layer. If two layers are arranged, the corrosion resistance of the heat transfer tube can be further enhanced by the synergistic effect of the characteristics of each resin. Moreover, it is preferable that the resin coating layer made into two layers shall be 100 micrometers-1 mm, the corrosion resistance of a heat exchanger tube will be acquired, and the thermal conductivity of a heat exchanger tube will not be impaired.
[0019]
In addition to the above PA / PP combination, a combination of PA / PA, PP / PP, PA / PE, or the like may be used. In this way, one or more types of resins are selected from resins with excellent properties such as shock absorption, water resistance, and chemical resistance, depending on the usage environment and purpose. By coating with one or more resin coating layers, it is possible to prevent damage due to stepping stones of thin metal tubes and oxidation due to mud splash etc., and improve the corrosion resistance and heat resistance of heat transfer tubes. .
[0020]
And since the metal heat-transfer body is provided in the outer peripheral surface of the said 1 layer or multiple layers of resin film layer, it is compared with the case where only the resin film layer is provided by the metal's outstanding thermal conductivity. It is possible to improve the efficiency of heat exchange with the fluid flowing outside the heat pipe. Moreover, in the prior art, since the resin coating layer was made thick in order to improve the corrosion resistance of the heat transfer tube, the heat dissipation characteristics of the heat transfer tube were poor. However, in the present invention, the metal heat transfer body provided on the outer peripheral surface of the resin coating layer also has impact resistance and promotes the protective power of the thin metal tube by the resin coating layer. The coating layer can be formed thinly, and in the case of heat dissipation, the heat dissipation characteristics of the heat transfer tube are further improved, and in the case of heat absorption, the heat absorption characteristics of the heat transfer tube are further improved to increase the heat exchange efficiency between the fluid flowing inside and outside the heat transfer tube. Can do.
[0021]
In addition, the presence of the resin coating layer having elasticity and flexibility allows the heat transfer body to be fitted to the thin metal tube with high fit, and can be stably and closely disposed. Therefore, the thermal conductivity between the heat transfer body and the resin coating layer is improved, and the heat dissipation characteristics and heat absorption characteristics of the heat transfer pipe are improved, and the vibration of the heat transfer pipe and the flow pressure of the fluid flowing around the outer periphery of the heat transfer body are improved. The durability of the heat transfer body is improved and excellent heat exchange performance can be maintained.
[0022]
In addition, the metal heat transfer body, if a thin metal tube is attached to the outer peripheral surface of the resin coating layer, and the thin metal tube is stretched to be in close contact with the small diameter metal tube through the resin coating layer, The entire outer peripheral surface of the resin coating layer can be covered with metal, and high heat dissipation characteristics or heat absorption characteristics can be obtained, thereby enabling efficient heat exchange.
[0023]
The heat transfer body is formed by spirally winding a metal strip around the outer peripheral surface of the resin coating layer, or spirally winding a metal wire having a circular cross section, an ellipse, a triangle, a quadrilateral, or the like. If it is formed by turning, the operation of providing the heat transfer body can be made easier. Further, the heat transfer body may be a metal fin member having an L-shaped section, a T-shape, a U-shape or the like wound around the outer periphery of the resin coating layer. The contact area is increased, the heat dissipation characteristics and heat absorption characteristics of the heat transfer tube are improved, and efficient heat exchange becomes possible.
[0024]
Moreover, when winding a strip, a fin member, a wire, etc. around the outer peripheral surface of the resin coating layer, the adjacent end portions are brought into close contact with each other without any gap, and the entire outer peripheral surface of the resin coating layer is adhered to the strip, fin member, wire. It may be covered with a belt, or a band material, a fin member, and a wire may be wound around a predetermined interval between adjacent end portions, and a part of the resin coating layer may be exposed to the outside. Also, when winding at regular intervals, if the spacing is wide and the surface area of the heat transfer body is small, it will be difficult to obtain high heat conductivity of the heat transfer tube, so there will be no loss of heat conductivity and stepping stones A strip, a fin member, and a wire are arranged at intervals and angles that can prevent the above.
[0025]
Further, the heat transfer body is formed by, for example, forming a metal strip around the outer peripheral surface of the resin coating layer and further winding a metal fin member around the outer surface of the strip, etc. A plurality of strips, fin members, and wires may be formed in combination, and the heat dissipation characteristics or the heat absorption characteristics can be further improved.
[0026]
In addition, when the heat transfer body is formed of a thin metal tube, a strip, or a wire, a resin outer peripheral fin having a L-shaped section, a T-shape, a U-shape, or the like is spirally formed on the outer peripheral surface of the heat transfer body. If it is wound, the impact resistance of the heat transfer tube against stepping stones can be enhanced by the elasticity of the resin. Further, even if the outer peripheral fin is made of resin, good heat dissipation characteristics and heat absorption characteristics can be obtained due to its large surface area, and the functionality of the heat transfer tube as a heat exchanger can be improved.
[0027]
Further, the metal fin member and / or the resin outer peripheral fin is provided with a turbulence generating means including any one of a pin, a protrusion, a strip-shaped plate material, an unevenness, a through hole, or a combination thereof on the outer peripheral surface. If provided, the surface area of the fin member and the outer peripheral fin can be further increased, and the heat exchange efficiency by the heat transfer tube can be further improved. Moreover, by these turbulent flow generating means, a spiral turbulent flow is generated in the fluid flowing outside the heat transfer tube, and the heat exchange efficiency can be further improved by peeling the boundary layer.
[0028]
In addition, the thin metal pipe can be obtained by providing at least one layer of an anticorrosive plating layer such as sacrificial corrosion on the outer surface and providing at least one resin coating layer on the outer peripheral surface of the anticorrosion plating layer. Further, the anticorrosion plating layer is protected by the resin coating layer, and the corrosion resistance of the heat transfer tube can be improved. Further, the anticorrosion plating layer may have a single layer structure using zinc, tin, tin-zinc alloy, nickel, zinc-nickel alloy, or the like, or a multilayer structure of two or more layers combining these. May be.
[0029]
In addition, in the heat transfer body formed of the above-mentioned thin metal tube, metal strip, metal fin member, metal wire, etc., at least one layer of sacrificial corrosion-resistant anticorrosion plating layer on the outer surface If it is provided, the corrosion resistance of the heat transfer tube can be further enhanced. Moreover, the plating process to the heat transfer body may be performed after providing any one of the heat transfer bodies on the outer peripheral surface of the resin coating layer, or a thin metal tube, a strip material, which has been previously plated. You may provide a fin member, a wire, etc. in the outer peripheral surface of a resin film layer.
[0030]
In addition, the resin coating layer and / or the resin-made outer peripheral fin may be made of resin if it contains particles and / or fibers made of metal or glass such as copper, aluminum, and stainless steel having higher thermal conductivity than the resin material. The heat conductivity of the coating layer and the outer peripheral fin is increased, and a heat transfer tube having excellent heat dissipation characteristics and heat absorption characteristics can be obtained, thereby enabling more efficient heat exchange.
[0031]
In particular, if the resin coating layer and / or the outer peripheral fin made of resin contain carbon nanofibers, the thermal conductivity of the resin material can be improved, and the heat dissipation characteristics or heat absorption characteristics of the heat transfer tube can be improved. It becomes. Moreover, the best heat dissipation characteristic or endothermic characteristic can be obtained if the carbon nanofiber is contained in an amount of more than 5 wt% and less than 30 wt%. If the carbon nanofiber content is 5 wt% or less, the heat transfer effect is not improved, and it is difficult to contain 30 wt% or more in the resin material. There is no big difference. The carbon nanofiber referred to in the present specification is a general term including all carbon materials of carbon nanotubes, carbon nanohorns, and other nano units in the nanotechnology field.
[0032]
【Example】
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially enlarged sectional view of a heat transfer tube according to a first embodiment of the present invention. The outer surface of each of the metal tube and the heat transfer body is provided with an anticorrosion plating layer, and the second embodiment shown in FIG. 2 is a heat transfer tube using a metal strip as the heat transfer body. The third embodiment shown is a heat transfer tube using a fin member having an L-shaped cross section as a heat transfer body. The fourth embodiment shown in FIG. 4 is a heat transfer tube using a fin member having a T-shaped cross section as a heat transfer body, and the fifth embodiment shown in FIG. 5 projects a pin on the fin member having a T-shaped cross section. The heat transfer tube provided with turbulent flow means, the sixth embodiment shown in FIG. 6 is a heat transfer tube having a U-shaped fin member as a heat transfer body, and the seventh embodiment shown in FIG. A heat transfer tube having a circular metal wire as a heat transfer body and two resin coating layers. The eighth embodiment shown in FIG. 8 is a heat transfer tube in which a resin-made outer peripheral fin is spirally wound around the outer peripheral surface of a heat transfer body formed of a thin metal tube. In the ninth embodiment shown in FIG. 9, a metal strip is disposed on the outer peripheral surface of the resin coating layer, and a metal fin member having an I-shaped cross section is further wound around the outer peripheral surface of the strip. It is a heat transfer tube that is turned into a heat transfer body.
[0033]
First, the first embodiment shown in FIG. 1 will be described in detail. (1) is a thin metal tube having a relatively thin outer surface with a tube diameter of 30 mm or less, a single wound steel tube having no copper plating, and an outer surface. Double-rolled steel pipe with copper plating, aluminum pipe, etc. are used. Then, the outer surface of the thin metal tube (1) is plated to provide an anticorrosion plating layer (2) such as sacrificial corrosion. The anticorrosion plating layer (2) is made of zinc, tin, tin-zinc. An alloy, nickel, zinc-nickel alloy or the like may be formed in one layer, or nickel is plated on the outer surface of the thin metal tube (1), and a zinc-nickel alloy is plated on the outer peripheral surface of the nickel. A plurality of layers such as a two-layer structure may be used. The formation of a plurality of anticorrosion plating layers (2) may be performed, for example, by the invention described in Japanese Patent No. 2750710, the invention described in Japanese Patent No. 2945555, or the method described in Japanese Patent Application Laid-Open No. 3-47987.
[0034]
Next, the resin coating layer (3) is adhered and coated on the outer peripheral surface of the anticorrosion plating layer (2) as described above using an extrusion molding apparatus or the like. In this embodiment, the resin coating layer (3) is formed of only one layer made of polyamide (PA) such as polyamide 12, polypropylene (PP), polyethylene (PE) or the like. The resin coating layer (3) may be formed by containing particles or fibers formed of a metal such as copper, aluminum or stainless steel or glass in the resin material, and heat conduction of the resin coating layer (3). You can increase the sex. Further, the resin coating layer (3) may be black. In the case of heat dissipation, the radiation characteristics of radiant heat are excellent, and in the case of heat absorption, the heat absorption is excellent, and the heat exchange efficiency can be further improved.
[0035]
In addition, by using carbon nanofibers such as carbon nanotubes and carbon nanohorns as fibers to be contained in the resin coating layer (3), the heat dissipation characteristics and the heat absorption characteristics of the resin coating layer (3) can be improved. . Moreover, it is preferable to contain such carbon nanofibers in a content of more than 5 wt% and less than 30 wt%, and a better heat transfer effect can be obtained and the heat transfer tube (7) can be easily produced.
[0036]
A metal heat transfer body (5) is provided on the outer peripheral surface of the resin coating layer (3). In the first embodiment shown in FIG. 1, the outer peripheral surface of the resin coating layer (3) is provided with copper, A thin metal tube (4) made of metal such as aluminum or stainless steel is packaged, and the outer peripheral surface of the thin metal tube (1) through the resin coating layer (3) by the method of extending the thin metal tube (4). A thin metal tube (4) is closely attached to the heat transfer body (5).
[0037]
And the outer peripheral surface of the said heat-transfer body (5) is plated, and the 2nd anti-corrosion plating layer (6) is provided. This second anticorrosion plating layer (6) is also composed of one layer of zinc, tin, tin-zinc alloy, nickel, zinc-nickel alloy, etc., like the anticorrosion plating layer (2) on the outer periphery of the thin metal pipe (1). They may be formed, or a combination of these layers may be formed. By providing the second anticorrosion plating layer (6), it is possible to prevent the heat transfer body (5) from being corroded and to further improve the corrosion resistance of the entire heat transfer tube (7).
[0038]
In the heat transfer tube (7) formed as described above, the thin metal tube (1) and the anticorrosion plating layer (2) are covered and protected with a resin coating layer (3) having shock absorption, water resistance, chemical resistance and the like. As a result, the metal pipe (1) and anti-corrosion plating layer (2) using steel pipes and aluminum pipes are more effective in preventing damage caused by stepping stones and oxidation due to mud splashes, etc., and have excellent corrosion resistance. Can be obtained. Further, in the prior art, the heat radiation characteristic is lowered by providing the resin coating layer (3). However, in the present invention, a metal heat transfer body (5) is provided on the outer peripheral surface of the resin coating layer (3). Therefore, the heat conductivity of the heat transfer tube (7) can be improved.
[0039]
In addition, since the metal heat transfer body (5) is also excellent in impact resistance, the resin coating layer (3) can be formed thinner than before, and the heat dissipation characteristics of the heat transfer tube (7) are improved. Will be further promoted. Therefore, heat exchange between the fluid flowing inside the heat transfer tube (7) and the fluid flowing outside can be efficiently performed via the heat transfer tube (7) having excellent heat radiation characteristics. It is possible to improve the quality of products such as oil cooling pipes of automobiles and construction machinery using (7), air conditioners that adjust the temperature and humidity of residential spaces.
[0040]
In the first embodiment, the anticorrosion plating layer (2) is provided on the outer surface of the thin metal pipe (1), and the second anticorrosion plating layer (6) is provided on the outer surface of the heat transfer body (5). This makes it possible to maintain excellent corrosion resistance even in a severe corrosive environment. However, in the present invention, a resin coating layer (3) is provided on at least the outer peripheral surface of the thin metal pipe (1), and the outer peripheral surface thereof is provided. A structure having a metal heat transfer body (5) may be provided, and the heat transfer tube (7) may be formed without providing the anticorrosion plating layer (2) or the second anticorrosion plating layer (6). Even in such a heat transfer tube (7), a product excellent in corrosion resistance and heat dissipation characteristics can be obtained by the resin coating layer (3) and the heat transfer body (5). In addition to the plating treatment, other surface treatments such as anodizing treatment may be applied to the thin metal tube (1) and the heat transfer body (5).
[0041]
In addition, the surface treatment operations such as plating and anodizing may be incorporated in the manufacturing process of the heat transfer tube (7). However, the small-diameter metal tube (1) or heat transfer body which has been subjected to the surface treatment in advance. The thin metal tube (4) for (5) may be used, and the productivity of the heat transfer tube (7) can be increased by omitting the surface treatment.
[0042]
In the second to seventh embodiments shown in FIGS. 2 to 7, as in the first embodiment, the anticorrosion plating layer (2) and the resin coating layer (3) are formed on the outer surface of the thin metal tube (1). The heat transfer body (5) provided on the outer peripheral surface of the resin coating layer (3) is made of a metal strip (8), a fin member (10), a wire (13), etc., which will be described later. Forming.
[0043]
First, in the second embodiment shown in FIG. 2, a flat plate-like long metal strip (8) is spirally wound around the outer peripheral surface of the resin coating layer (3). The heat transfer body (5) is formed on the outer peripheral surface of 3). Thus, since the work is simply to wind the strip (8), the heat transfer body (5) can be easily installed on the outer peripheral surface of the resin coating layer (3). In FIG. 2, the adjacent ends of the band material (8) are closely attached without any gap, and the entire resin coating layer (3) is covered with the band material (8). (8) may be wound and a part of the resin coating layer (3) may be exposed to the outside, so that the band material (8) can be saved and a simple operation can be performed. Moreover, when winding a strip | belt material (8) by a fixed space | interval, a strip | belt material (8) is arrange | positioned by the space | interval and angle which do not impair the thermal conductivity by a strip | belt material (8), and can prevent a stepping stone.
[0044]
Next, in the third embodiment shown in FIG. 3, a fin member (10) formed by bending a long and smooth metal plate into an L-shaped cross section is spirally formed on the outer peripheral surface of the resin coating layer (3). The heat transfer body (5) is formed by winding.
[0045]
Further, in the fourth embodiment shown in FIG. 4, a fin member (10) having a T-shaped cross section is used, and the smooth surface represented by the T-shaped horizontal bar is brought into contact with the resin coating layer (3) while this resin is being used. A fin member (10) is spirally wound around the outer peripheral surface of the coating layer (3) to form a heat transfer body (5). By forming the heat transfer body (5) with the fin member (10) as in the third and fourth embodiments, the contact area between the fluid flowing outside and the heat transfer body (5) is increased, and heat exchange is performed. Efficiency can be increased.
[0046]
Further, in the fifth embodiment shown in FIG. 5, similarly to the fourth embodiment, the heat transfer body (5) is formed by the fin member (10) having a T-shaped cross section, and both sides of the fin member (10) are further formed. A turbulent flow means for turbulent fluid flowing outside the heat transfer tube (7) is provided on the outer peripheral surface of the fin member (10) so as to project and fix in a direction perpendicular to the surface of the fin member (10). Yes. The pin (11) as the turbulent flow means is fixed in advance to the fin member (10) before being fixed to the outer peripheral surface of the resin coating layer (3), and the fin member (10) to which the pin (11) is fixed. Is wound and fixed around the outer peripheral surface of the resin coating layer (3). Further, as shown in FIG. 5, the pin (11) is fixed to the fin member (10) by opening a through hole (12) in the fin member (10) and inserting the pin (12) through the through hole (12). 11) is fixed to the fin member (10) at regular intervals or randomly by brazing or welding.
[0047]
Thus, by providing the pin (11) on the fin member (10), the surface area of the fin member (10) can be increased, and the heat exchange efficiency with the fluid flowing outside can be improved. Further, by projecting the pin (11) on the smooth outer surface of the fin member (10), a spiral turbulent flow of fluid is generated on both surfaces of the fin member (10), and the fin member (10) is spirally wound. The boundary layer that is likely to be generated between the fin members (10) is peeled off, and the heat exchange efficiency can be further improved by the heat radiation characteristics.
[0048]
In the fifth embodiment, one pin (11) is provided on both sides of the fin member (10) to serve as turbulent flow means. However, as another embodiment, the pin (11 ) Or a plurality of pins (11) on both sides or one side. Moreover, you may provide the appropriate protrusion and unevenness | corrugation of the shape different from a pin (11). Further, even if only the through hole (12) is provided without projecting the pin (11), the fluid can be turbulent. Further, as a different turbulent flow means, a strip-shaped plate material may be fixedly formed on the fin member (10) instead of the pin (11), and the surface area of the fin member (10) is further increased as compared with the pin (11). In addition, a large amount of spiral turbulence of the fluid is generated, and the heat exchange efficiency can be improved by the heat radiation characteristics due to the separation of the boundary layer. Further, it may be a turbulent flow means composed of any one of the pin (11), the through hole (12), the protrusion, the unevenness, a strip-shaped plate material, etc. Means may be formed.
[0049]
Further, even when the fin member (10) for the heat transfer body (5) of the third to fifth embodiments is wound, the adjacent ends of the fin member (10) are brought into close contact with each other so that the resin coating layer (3) A part of the outer peripheral surface of the resin coating layer (3) may be covered with the heat transfer body (5) or with a certain distance between the adjacent ends of the fin member (10). May be exposed to the outside, and in this case, the fin member (10) is wound at an interval and an angle at which stepping stones can be prevented to such an extent that the thermal conductivity of the fin member (10) is not impaired.
[0050]
Next, in the sixth embodiment shown in FIG. 6, a fin member (10) having a U-shaped cross section is placed on the outer peripheral surface of the resin coating layer (3) without impairing the thermal conductivity of the heat transfer body (5). The heat transfer body (5) is formed by spirally winding it at a certain interval to prevent stepping stones. Thus, by making the fin member (10) U-shaped in cross section, the contact area between the fluid and the heat transfer body (5) can be increased compared to the L-shaped or T-shaped fin member (10). Further, the heat exchange efficiency between the heat transfer body (5) and the fluid can be further increased.
[0051]
Further, the fin member (10) having a U-shaped cross section of the sixth embodiment and the fin members (10) having the L-shaped cross section of the third embodiment and the T-shaped cross section of the fourth embodiment are Although the surface of the projecting portion in the radial direction is formed smoothly, the surface may be formed in a wavy shape to increase the surface area of the fin member (10) and further increase the heat exchange efficiency.
[0052]
Further, in the seventh embodiment shown in FIG. 7, an anticorrosion plating layer (2) consisting of two layers of galvanization and chromate film is formed on the outer surface of a thin metal tube (1) using an aluminum tube. A PA12 first layer (14) having excellent adhesion to metal is provided on the outer peripheral surface of the anticorrosion plating layer (2), and the outer peripheral surface of the first layer (14) made of PA12 is water and chemical resistant. A second layer (15) made of PP having excellent properties is coated to form a resin film layer (3) having a two-layer structure. Then, by setting the thickness of the two resin coating layers (3) to 100 μm to 1 mm, the water resistance, chemical resistance, and impact resistance are high and the thermal conductivity is not impaired. . In addition to the above PA / PP, PA / PA, PP / PP, PA / PE, and the like can be given as examples of the combination of the resin having the two-layer structure Be . Moreover, it is good also as three or more resin film layers (3).
[0053]
Then, a resin wire layer is formed by spirally winding a metal wire (13) having a circular cross section around the outer peripheral surface of the resin layer (3) composed of the first layer (14) and the second layer (15). The heat transfer body (5) is formed on the outer peripheral surface of (3). Even when the wire (13) is used in this manner, the heat transfer body (5) can be easily installed on the outer peripheral surface of the resin coating layer (3). Moreover, as shown in FIG. 7, the resin film layer (3) may be entirely covered with the wire (13) by adhering the adjacent outer peripheral surface of the wire (13) without a gap, or the heat generated by the wire (13). The wire (13) may be wound around a certain distance so as to prevent stepping stones without impairing conductivity, and a part of the resin coating layer (3) may be exposed to the outside. Savings and more simple work. Further, although the wire rod (13) having a circular cross section is used in this embodiment, a cross section having an arbitrary shape other than a circle such as an ellipse, a triangle, a quadrangle, or the like may be used.
[0054]
Further, as in the seventh embodiment, the resin coating layer (3) composed of the first layer (14) and the second layer (15) or the resin coating layer (3) having three or more layers is formed by only one layer. You may apply to the resin film layer (3) of the 1st-6th Example.
[0055]
In addition, the strip material (8), the fin member (10), and the wire material (13) used in the second to seventh embodiments are plated or anodized after being placed on the outer peripheral surface of the resin coating layer (3). Surface treatment such as treatment may be performed, or the strip (8), fin member (10), wire (13) that has been subjected to the surface treatment may be used, and the heat resistance of the heat transfer tube (7) may be increased. It can be further increased. Further, the strip (8), the fin member (10), and the wire (13) may be wound continuously in a long length, or may be a short or ring-shaped strip (8) or fin member (10). ), The wire (13) may be provided on the outer peripheral surface of the resin coating layer (3) at a certain interval so as to prevent stepping stones without bringing the wire (13) into close contact with each other or without impairing the thermal conductivity of the heat transfer body (5). good. Further, a fin member (10) having an L-shaped cross section of the third embodiment and a fin member (10) having a U-shaped cross section of the sixth embodiment are provided with a pin (11), a protrusion, an unevenness, and the like as in the fifth embodiment. You may provide the turbulent flow means which consists of any 1 type or a combination of multiple types, such as a through-hole (12).
[0056]
In the third to seventh embodiments, the metal fin member (10) is used as the heat transfer body (5). However, in the eighth embodiment shown in FIG. 8, the heat transfer body (5) is used. Separately from this, the heat transfer tube (7) is provided with a resin outer peripheral fin (16), and the impact resistance of the heat transfer tube (7) against stepping stones and the like is enhanced by the good elastic force of the resin. That is, as shown in FIG. 8, the outer peripheral surface of the thin metal pipe (1) is galvanized and copper-plated to provide a two-layer anticorrosive plating layer (2), and the outer peripheral surface is coated with a resin coating such as PA. The layer (3) is coated, and a heat transfer body (5) composed of a thin metal tube (4) is provided on the outer peripheral surface thereof. The resin-made L-shaped outer peripheral fins (16) are spirally wound around the outer peripheral surface of the heat transfer body (5) at regular intervals. Even with such a resin-made outer peripheral fin (16), it is possible to obtain a heat transfer tube (7) which has good heat radiation characteristics due to its large surface area and is excellent not only in impact resistance but also in heat exchange efficiency. The outer peripheral fin (16) may be formed by containing particles or fibers formed of a metal such as copper, aluminum, stainless steel, or glass in the resin material, or may be formed of a black resin material. It is possible to increase the thermal conductivity of the outer peripheral fins (16) and enable more efficient heat exchange. Further, the resin material of the outer peripheral fin (16) may contain carbon nanofibers such as carbon nanotubes and carbon nanohorns in a content of more than 5 wt% and less than 30 wt%.
[0057]
In the first to eighth embodiments, the heat transfer body (5) is formed of only one of the metal pipe (4), the strip (8), the fin member (10), and the wire (13). However, in the ninth embodiment shown in FIG. 9, a metal strip (8) is disposed on the outer peripheral surface of the resin coating layer (3), and the cross section is I-shaped on the outer periphery of the strip (8). A heat transfer body (5) is formed by winding a metal-shaped fin member (10). Even in the case of such a heat transfer body (5), the heat transfer area of the heat transfer tube (7) can be increased, and the heat dissipation characteristics and heat absorption characteristics of the heat transfer tube (7) can be improved to improve the heat exchange performance. An excellent heat transfer tube (7) can be obtained. In addition to the combination of the strip (8) and the fin member (10), as another different embodiment, the metal pipe (4) and the strip (8) or the wire (13) or the fin member (10) The heat transfer body (5) may be formed by combining the strips (8) and the wire (13), or by combining the wire (13) and the fin member (10).
[0058]
【The invention's effect】
The present invention is configured as described above, and a resin coating layer having high impact resistance, water resistance, chemical resistance and the like is provided on the outer peripheral surface of a steel pipe, an aluminum pipe, and other small-diameter metal pipes. Since the metal heat transfer body having excellent heat conductivity is provided on the outer peripheral surface, a heat transfer tube having high corrosion resistance and heat dissipation characteristics or heat absorption characteristics can be obtained. Therefore, the durability of the heat transfer tube is enhanced, and efficient heat exchange between the fluid flowing inside the heat transfer tube and the fluid flowing outside can be performed for a long time. In addition, a resin coating layer is coated on the outer peripheral surface of a thin metal tube by extrusion molding, and a metallic heat transfer body is provided on the outer peripheral surface of the resin coating layer, so the structure of the heat transfer tube is simple and easy to manufacture. This can improve productivity.
[Brief description of the drawings]
FIG. 1 is a partially enlarged sectional view of a heat transfer tube according to a first embodiment of the present invention, in which a heat transfer body is formed by a thin metal tube.
FIG. 2 is a partially enlarged cross-sectional view of a heat transfer tube according to a second embodiment, in which a heat transfer body is formed of a band material.
FIG. 3 is a partially enlarged cross-sectional view of a heat transfer tube of a third embodiment, in which a heat transfer body is formed by a fin member having an L-shaped cross section.
FIG. 4 is a partially enlarged cross-sectional view of a heat transfer tube of a fourth embodiment, in which a heat transfer body is formed by a fin member having a T-shaped cross section.
FIG. 5 is a partially enlarged cross-sectional view of a heat transfer tube according to a fifth embodiment, in which a turbulent means is provided by projecting a pin on the surface of a fin member having a T-shaped cross section.
FIG. 6 is a partially enlarged cross-sectional view of a heat transfer tube according to a sixth embodiment, in which a heat transfer body is formed by a fin member having a U-shaped cross section.
FIG. 7 is a partially enlarged cross-sectional view of a heat transfer tube of a seventh embodiment, in which a heat transfer body is formed by a wire having a circular cross section.
FIG. 8 is a partially enlarged cross-sectional view of a heat transfer tube of an eighth embodiment, in which resin-made outer peripheral fins are spirally wound around the outer peripheral surface of a heat transfer body formed of a thin metal tube.
FIG. 9 is a partially enlarged cross-sectional view of a heat transfer tube of a ninth embodiment. Is formed.
[Explanation of symbols]
1 Small metal pipe
2 Anticorrosion plating layer
3 Resin coating layer
4 Thin metal pipe
5 Heat transfer body
6 Second anticorrosion plating layer
8 Band material
10 Fin member
11 pins
12 Through hole
13 Wire
16 peripheral fins

Claims (12)

A metal made of a thin metal tube, a thin metal tube attached in close contact with the outer peripheral surface of the outermost layer of the resin coating layer, and at least one resin coating layer provided on the outer peripheral surface of the thin metal tube A heat transfer tube having corrosion resistance, characterized by comprising a heat transfer body. A thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and a metal band wound in a spiral manner in close contact with the outer peripheral surface of the outermost layer of the resin coating layer A heat transfer tube having corrosion resistance, characterized by comprising a metal heat transfer body formed of a material . A thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and a metal fin wound in a spiral manner in close contact with the outer peripheral surface of the outermost layer of the resin coating layer A heat transfer tube having corrosion resistance, characterized by comprising a metal heat transfer body formed of a member . A thin metal tube, at least one resin coating layer provided on the outer peripheral surface of the thin metal tube, and a metal wire wound in a spiral manner in close contact with the outer peripheral surface of the outermost layer of the resin coating layer A heat transfer tube having corrosion resistance, characterized by comprising a metal heat transfer body formed in 1 .   The thin metal pipe is provided with at least one anticorrosion plating layer on the outer surface, and provided with at least one resin coating layer on the outer peripheral surface of the anticorrosion plating layer. Or a heat transfer tube having corrosion resistance of 4.   The heat transfer tube according to claim 1, 2, 3, or 4, wherein the heat transfer body is provided with at least one anticorrosion plating layer on the outer surface.   The heat transfer tube according to claim 1, 2 or 4, wherein the heat transfer body is formed by spirally winding a resin-made outer peripheral fin on the outer peripheral surface.   The resin coating layer and / or the outer peripheral fin made of resin contain metal and / or glass particles and / or fibers having higher thermal conductivity than the resin material. A heat transfer tube having corrosion resistance of 4 or 7.   9. The heat transfer tube having corrosion resistance according to claim 1, wherein the resin coating layer and / or the resin-made outer peripheral fins contain carbon nanofibers.   The heat transfer tube having corrosion resistance according to claim 9, wherein the carbon nanofiber is contained in an amount of more than 5 wt% and less than 30 wt%.   The fin member and / or the outer peripheral fin is characterized in that turbulent flow means comprising any one of a pin, a protrusion, a strip-shaped plate material, an unevenness, a through hole, or a combination thereof is provided on the outer peripheral surface. Heat transfer tube having corrosion resistance of 3 or 8.   The heat transfer tube having corrosion resistance according to claim 1, 2, 3, 4, 5, 8 or 9, wherein two resin coating layers are disposed on the outer peripheral surface of the thin metal tube.

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