Title:
ALUMINUM PIPE HAVING GROOVED INNER SURFACE AND PRODUCTION THEREOF
Document Type and Number:
Japanese Patent JP3402234
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain an aluminum pipe having a large number of grooves in the inner surface being used as the heating tube of a heat exchanger in which exposure of new aluminum surface is eliminated when the pipe is enlarged by providing an oxide coating layer of specified thickness on the inner surface of the pipe.
SOLUTION: An aluminum pipe 1 has a large number of grooves 2 in the inner surface applied with an oxide coating layer 3 of 5 μm thick or above. Al material of the aluminum pipe 1 having grooved inner surface is not limited and includes industrial pure Al, Al alloy, and the like. Even if a mandrel is pushed into the pipe in order to enlarge the pipe when the pipe is set in a heat exchanger, the oxide coating layer 3 is not cracked easily and the new aluminum surface is not exposed substantially on the inner surface of the pipe. Since seizure does not take place between the inner surface of the pipe and the mandrel when the pipe is enlarged, the groove 2 in the inner surface of the pipe is not collapsed and the mandrel can be pushed in well.
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| JPS61134590 | HEAT EXCHANGER TUBE |
| JPH1163877 | INTERNAL SURFACE GROOVED HEAT TRANSFER PIPE |
| JP2010060255 | HEAT EXCHANGER |
Inventors:
Tatsuya Toki
Hiroshi Koto
Hiroshi Koto
Application Number:
JP398999A
Publication Date:
May 06, 2003
Filing Date:
January 11, 1999
Export Citation:
Assignee:
Hitachi Cable Ltd.
International Classes:
F28F1/40; F28F1/32; F28F19/02; F28F21/08; (IPC1-7): F28F1/40; F28F1/32; F28F19/02; F28F21/08
Domestic Patent References:
| JP8136178A | ||||
| JP5873795A | ||||
| JP5322477A | ||||
| JP3207997A | ||||
| JP10246589A |
Attorney, Agent or Firm:
Nobuo Kinutani