Rock Drill Hydraulic Pressure Settings: Getting It Right

Correct hydraulic pressure settings are fundamental to rock drill performance and longevity. Incorrect settings cause poor performance, accelerated wear, and premature failures.

Percussion Pressure

Percussion pressure controls the impact energy of the drill. Set it to the manufacturer's recommended level for the rock conditions. Measure with a calibrated pressure gauge at the drill inlet port.

Rotation Pressure

Rotation pressure determines the torque available for turning the drill string. Set it high enough to maintain rotation without stalling, but not so high that it causes excessive wear on the rotation motor and chuck.

Feed Pressure

Feed pressure controls the force pushing the drill into the rock. The correct setting depends on rock hardness and drill size. Too high causes bit and drill wear; too low reduces penetration rate.

Flushing Pressure

Flushing pressure must be sufficient to remove cuttings from the hole. Minimum flushing pressure is typically 3-5 bar for water flushing. Insufficient flushing pressure causes cuttings accumulation and bit wear.

Pressure Measurement

Use calibrated pressure gauges to verify all settings. Check pressures at the drill, not just at the rig control panel — pressure drops in hoses and fittings can be significant.