rubber sealed journal bearing water well drill 12 1/4" steel tooth tricone bit iadc 216

bearing rubber sealing iadc 537 water well drill 6 1/2'' tci tricone roller rock bits

seal bearing 12 1/4'' 311.2mm Kingdream TCI rock tricone bit

7 5/8" api pin iadc 517 tungsten carbide tooth roller rock 17 1/2'' tricone-rock-bits

7 5/8" api pin yellow iadc 617 tungsten carbide tooth roller 17 1/2'' tricone bit drilling

6 5/8" api pin 10 5/8" sealed bearing iadc 447 tungsten carbide tooth three roller bit