GB/T 18704 TORICH Round Stainless Steel Clad Pipes For Structural Purposes

Surface delivery condition

Nominal outside diameter

Tolerance

Polishing,Polish

(SB,SP)

≤25

±0.25

＞25~40

±0.30

＞40~50

±0.35

＞50~60

±0.40

＞60~70

±0.50

＞70~80

±0.60

＞80

±1％D

Unpolished,Sand blasting(SNB,SS)

≤25

±0.30

＞25~50

±0.40

＞50

±1.0％D

Wall thickness(S)

Tolerance(high-grade)

Tolerance(medium grade)

≥0.8~2.0

±0.10

±0.20

＞2.0~3.0

±0.15

±0.30

＞3.0

±5％S

±10％S

No.

Unified digital code

New steel grade

Old steel grade

Chemical composition

C

Si

Mn

P

S

Ni

Cr

N

1

S35350

12Cr17Mn6Ni5N

1Cr17Mn6Ni5N

≤0.15

≤1.00

5.50~7.50

≤0.050

≤0.030

3.50~5.50

16.00~18.00

0.05~0.25

2

S35450

12Cr18Mn9Ni5N

1Cr18Mn8Ni5N

≤0.15

≤1.00

7.50~10.0

≤0.050

≤0.030

4.00~6.00

17.00~19.00

0.05~0.25

3

S30210

12Cr18Ni9

1Cr18Ni9

≤0.15

≤1.00

≤2.00

≤0.045

≤0.030

8.00~10.00

17.00~19.00

≤0.10

4

S30408

06Cr19Ni10

0Cr18Ni9

≤0.08

≤1.00

≤2.00

≤0.045

≤0.030

8.00~11.00

18.00~20.00

-

No.

Unified digital code

New steel grade

Old steel grade

Yield strength

R_p0.2/MPa

Tensile

Strength

R_m/MPa

Elongation A/

％

≥

1

S35350

12Cr17MnNi5N

1Cr17Mn6Ni5N

245

520

25

2

S35450

12Cr18Mn9Ni5N

1Cr18Mn8Ni5N

245

520

3

S30210

12Cr18Ni9

1Cr18Ni9

210

520

30

4

S30408

06Cr19Ni10

0Cr18Ni9

210

520