The industrial standard of “Technical Requirements for Cold Rolled Steel Units of Metal Clad Pipes”.drafted by Dalian Sangao Group has passed the approval of the State Metallurgical and Electromechanical Standardization Committee and was issued recently, Standard number: YB/T 4626-2017, Gongbiao.comhttp://www.csres.com/s.jsp?keyword=4626-2017&pageNum=1
