Stainless steel square tube classification: Square pipe seamless steel pipe and welded steel pipe (seam pipe) two categories. According to the cross-sectional shape and can be divided into square and rectangular tube, circular pipe is widely used, but there are also some semi-circular, hexagonal, equilateral triangle, octagonal shaped pipe. Square tube specification: 5*5~150*150 mm Thickness: 0.4~6.0 mm Grade: 304,304L,TP304,TP316L,316,316L,316Ti,321,347H,310SProduct:ASTM A312 stainless steel pipe(TP304/304L,TP316/316L,TP321,TP310S) 2.Process method:cold drawing/cold rolling. 3.Surface finish:Annealing&Pickling. 4.Schedule:Sch50s/10s/40s/80s. 5.Main grade:a.Austenitic