Standard：GB/T17396 Standard of China Metallurgical Industry
Uses: used in the manufacture hydraulic prop
Delivery status: hot-rolled
Grade and chemical composition（%）
|
Grade |
Chemical Composition
% |
|
C |
Si |
Mn |
P |
S |
Cr |
Ni |
Cu |
Nb |
Re
|
|
Not more than |
|
|
20 |
0.17~0.24 |
0.17~0.37 |
0.35~0.65 |
0.035 |
0.035 |
0.25 |
0.25 |
0.20 |
— |
— |
|
35 |
0.32~0.40 |
0.17~0.37 |
0.50~0.80 |
0.035 |
0.035 |
0.25 |
0.25 |
0.20 |
— |
— |
|
45 |
0.42~0.50 |
0.17~0.37 |
0.50~0.80 |
0.035 |
0.035 |
0.25 |
0.25 |
0.20 |
— |
— |
|
27SiMn |
0.24~0.32 |
1.10~1.40 |
1.10~1.40 |
0.035 |
0.035 |
0.30 |
0.30 |
0.30 |
— |
— |
|
Pipe size
mm |
Tolerance |
|
Ordinary Level |
Advanced |
|
OD |
±1% |
±0.75% |
|
Wall thickness |
≤20 |
±12.5% |
±10% |
|
＞20 |
+12.5%,-10% |
Mechanical Properties
|
Grade |
Sample heat treatment system |
Tensile strength
Rm，MPa |
Yield point
Rel，MPa |
Elongation
A，% |
Reduction of
ψ，% |
Impact energy
Aku2
J |
Annealed steel supply state Brinell hardness less than
min:HB |
|
Not less than |
|
20
35
45 |
— |
400
510
590 |
245
305
335 |
20
17
14 |
— |
— |
— |
|
27SiMn |
920℃±20℃ Quenching
450℃±50℃
Tempering
Coolant: oil or water |
980 |
835 |
12 |
40 |
39 |
217 |
NOTE: After consultation, but also for other brands of steel
Size deviation: outer diameter of the pipe according to GB / T17396 supply and wall thickness tolerances | 
Seamless oil pipe
