... of Steel Pipe: 6mm-20mm3) Steel grade of Steel Pipe: grade B , 20# , Q235 , ST 52 , ST374) Standards of Steel Pipe: ASTM A106 , ASTM 53 , API 5L and ... DIN2448,DIN17120,API 5L, API 5CT, ASTM A106, ASTM A53,ASTM A179,ASTM A210,ASTM A36,JISG3454,JISG3455,JISG3556,GOST8732,GOST8731MaterialGr. B, Gr. C; ... X42,X46,X52,X60,J55,K55,N80; st37,st42,st42-2,st45.8,st52,Gr 20,STPG410 ...