... .5,¢16,¢19,¢22,¢25,¢28,¢32,¢35 and so on.According to products size, the production lines are divided into small ... customers needs. After annealing, usually it is need to spray one coating on tubes inner wall. Some products do not need this procedure ... base coating, tubes come into oven to dry base coating. Printing machine print patterns on tubes surface. Usually upmost 4-6 colors ...