High Precision Seamless Steel Pipe
production standards:
GB/T 3639；GB/T 1591；GB/T 699；DIN2391；EN10305-1；ASTM A519
condition of delivery :
| condition of delivery | Code | Explain |
| Cold drawing or cold rolling / hard | +C | Final cold drawing or cold rolling without heat treatment |
| Stress relieving annealing after cold drawing or cold rolling | +SR | After final cold drawing or cold rolling, the steel tube is eliminated by stress annealing |
| annealing | +A | After final cold drawing, the steel tube is annealed |
| normalizing | +N | After final cold drawing, the steel pipe is normalized |
20#,45#, Q345B,Q345D,25Mn,27SiMn,E355,SAE1026,STKM13C, E460, 4130, 4140
Chemical composition:
| Chemical composition, % | |||||||||
| steel grade | C | Si | Mn | P | S | Cr | Ni | V | Al |
| ≤ | ≥ | ||||||||
| 20# | 0.17-0.24 | 0.17-0.37 | 0.35-0.65 | 0.035 | 0.035 | 0.250 | 0.250 | / | / |
| 45# | 0.42-0.50 | 0.17-0.37 | 0.50-0.80 | 0.035 | 0.035 | 0.250 | 0.300 | / | / |
| Q345B | ≤0.2 | ≤0.5 | 1.00-1.60 | 0.030 | 0.030 | 0.300 | 0.250 | 0.08 | / |
| Q345D | ≤0.2 | ≤0.5 | 1.00-1.60 | 0.030 | 0.030 | 0.250 | 0.250 | 0.150 | 0.015 |
| 25Mn | 0.22-0.29 | 0.17-0.37 | 0.70-1.00 | 0.035 | 0.035 | / | / | / | / |
| 27SiMn | 0.24-0.32 | 1.10-1.40 | 1.10-1.40 | 0.035 | 0.035 | 0.300 | 0.300 | / | / |
| E355(ST52) | ≤0.22 | ≤0.55 | ≤1.6 | 0.025 | 0.025 | 0.250 | 0.250 | / | / |
| SAE1026 | 0.22-0.28 | 0.15-0.35 | 0.60-0.90 | 0.040 | 0.050 | / | / | / | / |
| E460 | ≤0.22 | ≤0.60 | 1.20-1.60 | 0.030 | 0.030 | 0.300 | 0.800 | 0.20 | 0.02 |
| 4130 | 0.28-0.33 | 0.15-0.35 | 0.40-0.60 | 0.040 | 0.040 | 0.80-1.10 | / | / | / |
| 4140 | 0.36-0.43 | 0.15-0.35 | 0.75-1.00 | 0.040 | 0.040 | 0.80-1.10 | / | / | / |
Mechanical property
| steel grade | Delivery status | |||||||||||
| +C | +SR | +A | +N | |||||||||
| Rm/Mpa | A/% | Rm/Mpa | Rel/Mpa | A/% | KV2/J | Rm/Mpa | A/% | Rm/Mpa | Rel/Mpa | A/% | KV2/J | |
| 20(ST45) | 550 | 5 | 520 | 375 | 12 | — | 390 | 21 | 440～570 | 255 | 21 | — |
| 45 | 645 | 4 | 600 | 450 | 6 | — | 590 | 14 | 540 | 340 | 18 | — |
| Q345 | 680 | 8 | 580 | 450 | 10 | 27 | 450 | 22 | 490～630 | 355 | 22 | 34 |
| 25Mn(SAE1026) | 650 | 6 | 560 | 430 | 10 | — | 430 | 20 | 460 | 300 | 20 | — |
| E355(ST52) | 680 | 8 | 580 | 450 | 10 | 27 | 450 | 22 | 490～630 | 355 | 22 | 34 |
| 27SiMn | 750 | 4 | 650 | 520 | 8 | — | 600 | 10 | 650 | 430 | 14 | — |
| E460 | 690 | 620 | 13 | |||||||||
Note: Rm: tensile strength; Rel: lower yield strength; A: elongation;
KV2: shock absorption energy.
Q345 shock absorption energy in accordance with B, C, D, E, respectively, corresponding to 20°C、0°C、-20°C、-40°C.
We can produce outer diameter 4mm-273mm, high precision cold drawn steel tube, cold-rolled steel tube, precision steel pipe, stainless steel tube, stainless steel tube wall thickness 0.1mm-25mm, accuracy up to /+0.025 mm, roughness of 0.2.
It is mainly used in hydraulic system pipes, automobile manufacturing pipelines, military industry, construction machinery, railway locomotives, aerospace, shipbuilding, petrochemical, power plants, boiler equipment, etc..
There are 6 main characteristics of our product:
1. There is no oxide layer on the inner wall and outer wall.
2. No leakage under tremendous pressure.
3. High accuracy.
4. High finish.
5.Cold bending without deformation.
6.No combustion, shrinkage, flattening, no cracks.
