Non-Magnetic Drill Collar
Time：2016/11/06 Traffic：
| Fishing Neck OD | Yield Strength Rf(MPa) | Tensile Strength Rm(MPa) | Elongation Ali(%) | Reduction of Area (%) | Impact Value (Joule) | Hardness HB |
| 3 1/2”-6 7/8” | ≥758 | ≥827 | ≥18 | ≥45 | ≥81J(RT) | 285～341 |
| 7”-11” | ≥689 | ≥758 | ≥20 | ≥45 | ≥81J(RT) | 285～341 |
B magnetic field gradient: Max. Deviation of the Magnetic field in the inner hole to uniform magnetic field: ≤±0.05μT
C intergranular corrosion (Anti corrosion): as per ASTM A262E for intergranular corrosion test.
