Protect your tools. Boost your results.
Guidelines for safe and efficient roller cone bit operation
- Be careful when screwing the drill bit on and off to avoid damage.
- Avoid applying excessive pressure when screwing off or on.
- Ensure correct installation of unscrewing device, no foreign objects on platform.
- Clean threads of drilling rod and new bit, apply anti-seize compound.
- Perform coupling at low speed and low torque.
- Apply reduced load and speed according to “rule of thirds”:
➤ 2nd third → 2/3 of the recommended parameters.
➤ Final → regular parameters.
- After breaking-in, that cone temperatures are balanced.
- Purge cones to remove fitting grease.
- Maintain pressure differential ≥ 2.8 bar for bearing protection.
- Ensure ascending stream speed:
≥ 2130 m/min for heavy cuttings.
- Signs of poor hole cleaning:
➤ Increased air feed pressure.
➤ Excessive cuttings at the hole bottom.
➤ Severe wear/damage to the bit leg back.
- Always engage air feed before lowering the bit; keep it engaged until drilling completion.
- Rotate the bit when raising/lowering to clean cuttings and prevent ingress into bearings.
- In water-saturated formations or with water injection, maximize pressure differential.
- Prevent bit from falling to avoid bearing/weld seam damage.
- Check back flow valve and cone rotation before mounting new bit.
- For long downtimes, manually rotate cones to ensure free running.
- Check air pressure at intervals; ensure no obstacles in rod or shackle.
- Inspect blunted bits for foreign materials; log pressure values at each bit change.
- Inspect bit components for cracks, breaks, or jamming.
- Avoid bent rods/components to prevent irregular loads.
- Apply sufficient but not excessive load for effective rock chipping.
- Match rotation speed to rock type:
➤ High speed → higher ROP, but reduced penetration per revolution and increased bit wear
- Never apply load to the bit without rod rotation.
- Avoid drilling-in with a new bit into an existing hole to prevent cone jamming or breakage.
- Clean used bits from cuttings.
- Examine wear pattern and log details.
- If large tungsten carbide chips appear → reduce speed/load.
- If erosive wear or cone top loss occurs with central blowing → switch to lateral blowing.