Standard:GB18248 Standard of China Metallurgical Industry
Uses: used in the manufacture of cylinders
Delivery status: hot-rolled
Grade and chemical composition
Trademark |
C |
Si |
Mn |
P |
S |
P+S |
Cr |
Mo |
Ni |
Cu |
37Mn |
0.34~0.40 |
0.10~0.30 |
1.35~1.65 |
≤0.030 |
≤0.030 |
≤0.055 |
≤0.30 |
-- |
≤0.30 |
≤0.20 |
30CrMo |
0.26~0.34 |
0.17~0.37 |
0.40~0.70 |
≤0.030 |
≤0.030 |
≤0.055 |
0.80~1.10 |
0.15~0.25 |
≤0.30 |
≤0.20 |
35CrMo |
0.32~0.40 |
0.17~0.37 |
0.40~0.70 |
≤0.030 |
≤0.030 |
≤0.055 |
0.80~1.10 |
0.15~0.25 |
≤0.30 |
≤0.20 |
NOTE: After consultation, cylinders and other brands produce 34CrMo4 tube。
Size deviation
Mechanical Properties
mark
|
Sample heat treatment |
Mechanical Properties |
Quenching (normalizing) |
Tempering |
Tensile strength
MPa |
Yield Strength
MPa |
Rear
ElongationA
% |
Impact energy J |
Temperature |
Coolant |
Temperature |
Coolant |
Not less than |
37Mn |
840 |
Water, oil |
600 |
空 |
750 |
630 |
16 |
55 |
30CrMo |
880 |
Water, oil |
540 |
Water,oil |
930 |
785 |
12 |
63 |
35CrMo |
850 |
Oil |
550 |
Water,oil |
980 |
835 |
12 |
63 |
Specification Table:GB18248 Series
外径 OD |
Wall thickness Mm |
60 |
3.5 |
70 |
3.5 |
89 |
4.5 |
108 |
4.0、4.5、5.0、5.5、6.0 |
121 |
4.5 |
127 |
4.5、7.5 |
140(139.7) |
4.5、5.0、8.0 |
159 |
5.0、5.5 |
165 |
5.0 |
180 |
7.0、8.0 |
219 |
6.3、6.5、7.0 |
229 |
6.3、7.0 |
232 |
6.0 |
267 |
7.0 |
273 |
7.5、8.2、9.0 |
NOTE: After consultation, but also for other specifications steel pipe |