Tolerance

Grade

OD

WT

Cold-drawn

OD (mm)

Tolerance (mm)

Tolerance (mm)

＜114.3

±0.79

－12.5％

≥114.3

－0.5％/＋1％

Mechanical Property

Standard

Grade

T.S.(MPa)

Y.S.(MPa)

Hardness

API SPEC 5CT

J55

≥517

379～552

K55

≥517

≥655

N80

≥689

552～758

L80(13Cr)

≥655

552～655

≤241HB

P110

≥862

758～965

Standard

Grade

Chemical Composition (%)

C

Si

Mn

P

S

Cr

Ni

Cu

Mo

V

Als

API SPEC 5CT

J55K55 (37Mn5)

0.34～0.39

0.20～0.35

1.25～1.50

≤0.020

≤0.015

≤0.15

≤0.20

≤0.20

≤0.020

N80       (36 Mn2V)

0.34～0.38

0.20～0.35

1.45～1.70

≤0.020

≤0.015

≤0.15

0.11～0.16

≤0.020

L80(13Cr)

0.15～0.22

≤1.00

0.25～1.00

≤0.020

≤0.010

12.0～14.0

≤0.20

≤0.20

≤0.020

P110 (30CrMo)

0.26～0.35

0.17～0.37

0.40～0.70

≤0.020

≤0.010

0.80～1.10

≤0.20

≤0.20

0.15～0.25

≤0.08

≤0.020