1. The first to clean the surface of the metal hose, and maintain neat;
2. The second is that the surface layer is deserved, and this whole process can completely place the metal hose among the dehydrate. The pH value of the dehydrate is preferably in 13, and the time is not less than half an hour. Wash with cold water after removal.
3. The next can be carried out, the pH of the acid lotion is 3, and the solution time is not good at ten minutes, and the pickling was washed after washing;
4. Black treatment: the pool concentration value pH 2-4, the solution is about ten minutes, and it is extremely clean after the black;
5. Finally carry out wind dry, oil;
In accordance with the 5th point, you can carry out the black treatment of the heating tube is still a very reasonable way.