Hydraulic Breaker Cylinder Assembly

A: Symptoms: Dirty hydraulic oil with metal debris, weak striking force, rising oil temperature and oil leakage.

Causes: Contaminated hydraulic oil, insufficient lubrication, blank firing, damaged piston ring or deformed cylinder bore.

Solution: Polish for minor scratches. Replace the piston if severely scored. Clean the hydraulic circuit and replace oil & filters.

A: Symptoms: Abnormal noise, unstable impact power, metal chips in oil.

Causes: Frequent blank firing, the chisel not pressed against the working surface, mismatched hardness of chisel, continuous side loading.

Solution: Cracked or chipped pistons cannot be repaired and must be replaced. Avoid blank firing and side loading. Use matched chisels.

A: Symptoms: Enlarged fitting clearance, lower striking efficiency, heavy vibration and oil leakage.

Causes: Long-term impact friction and failed oil film protection.

Solution: Replace the piston once clearance exceeds factory limits to prevent secondary damage to the cylinder.

A: Symptoms: Rapid seal failure, cross oil leakage and unstable pressure.

Causes: Aged high-temperature seals, scratches during assembly and repeated hydraulic impact.

Solution: Replace the piston if seal grooves are damaged; changing seals alone cannot solve the root problem.

A: Symptoms: The breaker stops striking completely.

Causes: Overheating, poor lubrication, dirt jamming and thermal expansion of piston.

Solution: Cool down before disassembly. Inspect cylinder bore, remove contaminants and replace damaged components.

A: Symptoms: Poor assembly locking, blocked oil path and abnormal striking.

Causes: Incorrect torque or rough disassembly.

Solution: Replace the piston when threads are damaged.

A: Symptoms: Poor striking power, low performance on hard rock. Causes: Worn cup seal, incorrect N₂ pressure and heavy impact load.

Solution: Test N₂ pressure separately. Replace the accumulator seal set if the cup is broken and recharge N₂ to standard value.

A: Symptoms: Intermittent striking, no impact, uncontrolled continuous hammering, unstable striking frequency.

Causes: Contaminants jamming the spool or spool wear.

Solution: Clean the valve assembly; replace the directional valve if worn, and install a return oil filter.

A: Symptoms: Persistent oil leakage and metal debris in oil.

Causes: Dry firing, long-time side loading, piston seizure or overpressure.

Solution: Hone for minor damage. Replace the whole middle cylinder once cracks or deep scoring appear.

A: Incorrect N₂ charging pressure

Too high N₂ pressure keeps the diaphragm continuously squeezed.

Too low pressure leads to a large stroke of hydraulic impact; the diaphragm bends repeatedly and suffers fatigue tearing.