How a Hydraulic Breaker Works
Complete technical series on hydraulic breaker working principles — piston mechanism, nitrogen accumulator, control valve, nitrogen chamber, and chisel types explained in depth.
The Percussion Cycle at a Glance
Hydraulic pump
supplies 150–200 bar
Control valve
directs oil to piston
Piston up-stroke
compresses N₂ gas
Power stroke
N₂ + oil accelerate piston
Impact
stress wave fractures rock
Series Articles
Read in order for a complete understanding, or jump to the topic you need.
Key Technical Concepts
Core engineering principles covered across the series.
Impact Energy
E = ½mv²Kinetic energy of the piston at the moment of impact, measured in joules.
Accumulator Amplification
3–8× powerThe accumulator compresses energy over the slow up-stroke and releases it over the fast down-stroke.
Nitrogen Pre-charge
25–80 barGas pressure at rest. Must be checked cold every 50 hours. Critical for correct percussion timing.
Stress Wave Transmission
~5,100 m/sImpact energy travels through the chisel as a compressive stress wave at the speed of sound in steel.
Control Valve Clearance
5–15 μmSpool-to-bore clearance. Smaller than a human hair — explains why oil cleanliness is critical.
Impact Frequency
400–1200 BPMBlows per minute. Determined by hydraulic flow rate, stroke length, and nitrogen pressure.