(1) Seamless tubes-cold drawn tubes, extruded tubes and cold rolled tubes.

(2) Welded pipe:

(a) According to the process classification-gas shielded welded pipe, arc welded pipe and resistance welded pipe (high frequency and low frequency).

(b) According to the weld-straight welded pipe and spiral welded pipe.

2. Classification by wall thickness-thin-walled steel pipe and thick-walled steel pipe

3, according to the material classification:

(1)304 stainless steel water pipe;

(2 )304L stainless steel water pipe;

(3)3 16 stainless steel water pipe;

(4)3 16L stainless steel water pipe;