In API 5CT, raw materials are divided into four groups. Group 1 is H, J, K, N, group 2 is C, L, M, T, group 3 is P, and group 4 is Q. Among them, there are distinctions such as J55, K55 and N80-1N80-O. Basically, they are divided according to the numerical range of material properties (steel grade, rolling, heat treatment, and finally the performance). As for the classification of steel grades in each group, they are also divided according to their properties.
GNEE Supply API 5CT OCTG Tubing Mechanical properties：
| Standard | Grade | Tensile Strength（MPa） | Yield Strength（MPa） |
| API SPEC 5CT | J55 | ≥517 | 379～552 |
| K55 | ≥517 | ≥655 | |
| N80 | ≥689 | 552～758 | |
| L80(13Cr) | ≥655 | 552～655 | |
| P110 | ≥862 | 758～965 |
GNEE Supply API 5CT Casing Chemical Composition ：
| 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 | |
GNEE Supply Dimensional Deviation of API 5CT Oil Piping:
| Dimensional Deviation | ||
| Items | Allowable Deviation | |
| Out Diameter | Pipe Body | D≤101.60mm±0.79mm |
| D≥114.30mm +1.0% | ||
| -0.5% | ||
| Wall Thickness | -12.5% | |
| Weight | Each Piece | +6.5% |
| +3.5% | ||
GNEE Supply Length Range of API SPEC 5CT Casing Pipe
| Length | |||
| Item | Scope 1 | Scope 2 | Scope 3 |
| Tubing | 6.10-7.32m | 8.53-9.75m | – |
| Casing | 4.88-7.62m | 7.62-10.36m | 10.36-14.63m |
GNEE Supply API SPEC 5CT Casing and Piping
