Structure steel pipe and other special steel pipe is a hot-rolled (extruded) and cold drawn (rolled) seamless pipe made of stainless steel for corrosion-resistant pipes and structural parts and parts for chemical, petroleum, textile, medical, food and machinery industries. Mainly used for general structure and mechanical processing, its representative material:GB/T 8162 45#,20#,10#,ASTM A519 4140,4130 and so on.
Structural steel tubes are hot rolled seamless steel tubes and welded steel tubes. Seamless steel tubes for structure are divided into hot rolled and cold drawn types according to GB/T8162-2008. The outer diameter of hot-rolled steel pipe is 32-630mm, and the wall thickness is 2.5-75mm. The outer diameter of cold-drawn steel tube is 5-200mm, and the wall thickness is 2.5-12mm. Welded steel pipe is made of steel plate or strip after crimping forming. Straight welded steel tubes shall have an outside diameter of 5-508mm and a wall thickness of 0.5-12.7mm, and shall comply with the provisions of GB/T3793-2008. The welded steel pipe used for low-pressure fluid transportation is also called general welded pipe, commonly known as black pipe. The specifications are expressed in millimeters of nominal caliber, which shall comply with the provisions of GB/T3091-2008.
Main grades of the Structural Steel Pipe
Standard
Grade
ASTM A53
GR.A
GR.B
ASTM A106
GR.A
GR.B
GR.C
GB/T 8162
10#
20#
35#
45#
Q345A
20Cr
40Cr
20Mn2
45Mn2
40CrB
42CrMo
Q345D
Q345E
20CrMo
35CrMo
Q345B
27SiMn
A345C
15CrMo
ASTM A519
1020
1035
1045
4130
4140
DIN1629
St37.0
St44.0
St55
St52.0
DIN17175
St35.8
17Mn4
13CrMo44
EN10297
E355
C45
34CrMo4
JIS G3441
SCM 420TK
SCM440TK
JIS G3445
STKM13A
STKM19A
Seamless steel tubes are mainly used for general structure and mechanical processing.