| 摘要 |
Hardfacing the principal bearing surface of a drill pipe with an alloy having the composition of: 50-65% Cobalt, 25-35% Molybdenum, 1-18% Chromium, 2-10% Silicon and less than 0.1% Carbon reduces the friction between the drill string and the casing or rock. As a result, the torque needed for the rotary drilling operation, especially directional drilling, is decreased. The alloy also provides excellent wear resistance on the drill string while reducing the wear on the well casing. |
