| 摘要 |
This invention concerns tubes for the use at high temperatures or any other aggressive environment. Tubes according to the invention have a coating consisting of a layer of aluminium and aluminium oxide with a thickness of at leat 0,3 mm on the outside of the tubes. The coating can consist of many layers and preferably be put on using flame spraying, high velocity spraying, plasma spraying or any other thermal spraying technique or a combination fo these methods. After the coating has been put on, it is oxidized by heating to ca 1050 C during at least four hours. |
