Processing mode

Diameter

Length

Linearity

Precision

Roughness of inner hole

Cold rolling

30-100

≤12M

0.3-1.0

H8-H10

0.4-1.6

Cold drawn

30-250

≤12M

H8-H10

0.8-1.6

Grinding

40-500

≤12M

1000

H8-H9

0.4-0.8

Rolling

40-400

≤7M

H8

0.4

Model

Item

Cold drawn (rolling) tube

metallic cut pipe

20

Intensity of tensionσbN/mm²

≥510

≥390

Elongation rate δ5%

≥5

≥20

45

Intensity of tension σbN/mm²

≥647

≥590

Elongation rateδ5%

≥4

≥4

16Mn

Intensity of tensionσbN/mm²

≥640

Elongation rateδ5%

≥10

27SiMn

Intensity of tensionσbN/mm²

≥840

Elongation rateδ5%

≥7.5

Inner diameter

warp of wall thickness

H8

H9

H10

30

+0.033

0

+0.052

0

+0.084

0

±5%

30-50

+0.039

0

+0.062

0

+0.100

0

50-80

+0.046

0

+0.074

0

+0.120

0

80-120

+0.054

0

+0.087

0

+0.140

0

120-180

+0.063

0

+0.100

0

+0.160

0

180-250

+0.072

0

+0.115

0

+0.185

0

250-315

+0.081

0

+0.130

0

+0.210

0

315-400

+0.089

0

+0.140

0

+0.230

0