The honing/skived and roller burnished seamless steel pipe is cold draw both inside and out, then is given tempering treatment with a tensile strength of up to 520N / mm2 or more. Our factory improves upon the work with our own precision honing/skived roller burnished, using the diameter tolerance of H5~H10. It helps to extend the life of the cylinder, and reduces the wear of the seal.
Specifications of major steel material:
Tolerance of ID and WT
Length and cut tolerance
Length ≤ 500mm , +2mm
> 500mm ≤ 2000mm, +3mm
> 2000mm ≤ 5000mm, +5mm
> 2000mm ≤ 7000mm, +10mm
Standard:DIN 2391,EN10305
Material: St45,St52,E355
Chemical composition
9. Mechanical Properties
Tube ends
Tube ends shall be cut nominally square to the axis and free from burs
11.Delivery condition:BKS
Appearance
Tube shall have a smooth internal and external surface consistent with cold working process, tube inner surface should be free from rust, scratches and other surface
irregularities
Specifications of major steel material:
Processing form | I.D.mm | Length | Straightness | I.D.tolerance | I.D.Roughness(RA) |
Cold-rolled | 30-100 | ≤12M | 0.3-1.0/1000 | H8-H10 | 0.4-1.6um |
Cold-drawn | 30-250 | ≤12M | H8-H10 | 0.8-1.6um | |
Hone | 40-500 | ≤12M | H8-H9 | 0.4-0.8um | |
SRB | 50-250 | ≤9M | H8 | 0.1-0.4um |
Size of inside Diameter(mm) | ID Tolerance | Tolerance of wall thickness | ||
30 | +0.0330 | +0.0520 | +0.0840 | <120mm(OD) ±5% >120mm up to 210mm±7.5% >210mm ±10% |
>30-50 | +0.0390 | +0.0620 | +0.1000 | |
>50-80 | +0.0460 | +0.0740 | +0.1200 | |
>80-120 | +0.0540 | +0.0870 | +0.1400 | |
>120-180 | +0.0630 | +0.1000 | +0.1600 | |
>180-250 | +0.0720 | +0.1150 | +0.1850 | |
>250-315 | +0.0810 | +0.1300 | +0.2100 | |
>315-400 | +0.0890 | +0.1400 | +0.2300 | |
Length ≤ 500mm , +2mm
> 500mm ≤ 2000mm, +3mm
> 2000mm ≤ 5000mm, +5mm
> 2000mm ≤ 7000mm, +10mm
Standard:DIN 2391,EN10305
Material: St45,St52,E355
Chemical composition
Steel grade | Chemical composition,% | |||||
C | Si | Mn | P | S | Cr | |
≤ | ||||||
St45 | 0.17-0.24 | 0.17-0.37 | 0.35-0.65 | 0.035 | 0.035 | 0.250 |
ST52(E355) | ≤0.22 | ≤0.55 | ≤1.6 | 0.025 | 0.025 | 0.25 |
SAE1026 | 0.22-0.28 | 0.15-0.35 | 0.60-0.90 | 0.040 | 0.050 | / |
27SiMn | 0.24-0.32 | 1.10-1.40 | 1.10-1.40 | 0.035 | 0.035 | 0.300 |
20# | 0.17-0.24 | 0.17-0.37 | 0.35-0.65 | 0.035 | 0.035 | 0.250 |
Delivery condition | BK Cold finished(hard) | BKS Cold drawn and stress-relieved | |||
Steel grade | Rm Mpa | Elongation A5(%) | Rm MPa | ReH MPa | Elonggation A5(%) |
ST45 | ≥550 | ≥5 | ≥520 | ≥375 | ≥15 |
ST52(E355) | ≥640 | ≥5 | ≥600 | ≥520 | ≥14 |
SAE1026 | ≥640 | ≥5 | ≥600 | ≥510 | ≥15 |
16Mn | ≥640 | ≥5 | ≥600 | ≥520 | ≥14 |
20# | ≥550 | ≥8 | ≥520 | ≥375 | ≥15 |
Tube ends
Tube ends shall be cut nominally square to the axis and free from burs
11.Delivery condition:BKS
Appearance
Tube shall have a smooth internal and external surface consistent with cold working process, tube inner surface should be free from rust, scratches and other surface
irregularities