The technical requirements of the galvanized steel(1)

1. Brand and chemical composition(galvanized steel)
The grade and chemical composition of steel for galvanized steel pipe shall comply with the grade and chemical composition of steel for black pipe specified in GB 3092.

2. Manufacturing method(galvanized steel)
The manufacturing method of black pipe (furnace welding or electric welding) shall be selected by the manufacturer. Hot dip galvanizing method shall be adopted for galvanizing.

3. Thread and pipe joint(galvanized steel)
a: For galvanized steel pipes delivered with threads, the threads shall be turned after galvanizing. The thread shall comply with Yb 822.
b: Steel pipe joints shall comply with Yb 238; Malleable cast iron pipe joints shall comply with Yb 230.

4. Mechanical properties the mechanical properties of steel pipes before galvanizing shall comply with the provisions of GB 3092.(galvanized steel)

5. Uniformity of galvanized coating galvanized steel pipes shall be tested for uniformity of galvanized coating. The steel pipe sample shall be continuously immersed in copper sulfate solution for 5 times and shall not turn red (copper plating color).