... ship, liquid service, petroleum cracking, chemical ferticizer equipment, drawing-oil-equipment and structure purposes.6.Surface: oiled or black ... Galvanized welded steel pipe 1.Quality :Q195, Q215, Q235, Q345 , M6, M8, SPHC , etc . 2.Zinc coating :80gms-275gms ... , liquid service, petroleum cracking, chemical ferticizer equipment, drawing-oil-equipment and structure purposes.6.Surface: oiled or black ...