... .the diameter of Spiral steel pipe is from φ219 to φ2850mm and wall thickness is from 5mm to 25mm. the brand of our product ... is WUZHOU. 2.Our product comply with the standard of SY/T5037-2000, GB/T9711.1-1997 and API SPEC ... /3, DIN 1629/4, ASTM A53-2007, ASTM A210-1996, API 5LGrade16Mn, ST35-ST52, Q195-Q345Grade16Mn, St37, St52, St52.4, Q235 ...