A rock breaker (also called a hydraulic breaker, hydraulic hammer, or rock hammer) is an attachment commonly mounted on excavators, backhoes, or skid steers to break rocks, concrete, and other hard materials. *Main Parts of a Hydraulic Rock Breaker* *1. Chisel (Tool Bit)* * The working end that directly strikes the rock. * Available in different shapes: * Moil point (general rock breaking) * Chisel tool (concrete demolition) * Blunt tool (secondary breaking) *2. Front Head (Tool Holder)* * Holds and guides the chisel. * Contains bushings that reduce wear. *3. Bushings* * Wear-resistant sleeves between the tool and housing. * Prevent excessive movement of the chisel. *4. Piston* * The main moving component inside the breaker. * Accelerated by hydraulic pressure and strikes the top of the chisel. *5. Control Valve* * Directs hydraulic oil flow to move the piston up and down. * Controls the breaker cycle automatically. * 6. Accumulator* * Stores pressurized nitrogen gas. * Absorbs hydraulic pressure fluctuations and improves impact energy. * 7. Nitrogen Chamber (Back Head)* * Contains compressed nitrogen gas. * Assists piston acceleration and impact force. *8. Cylinder Body* * Houses the piston and hydraulic passages. * Forms the main structure of the breaker. * 9. Side Plates / Housing* * Protective outer frame. * Shields internal components from debris and impacts. * 10. Mounting Bracket* * Connects the breaker to the excavator boom and stick. * 11. Hydraulic Hoses* * Supply and return hydraulic oil from the carrier machine. - Working Mechanism Step 1: Hydraulic Oil Enters Hydraulic oil from the excavator pump enters the breaker through the pressure line. Step 2: Piston Moves Up The control valve directs oil to lift the piston, compressing nitrogen gas in the back head. Step 3: Valve Shifts When the piston reaches a certain position, the valve redirects oil flow. Step 4: Piston Accelerates Downward Hydraulic pressure and expanding nitrogen gas push the piston downward at high speed. Step 5: Impact The piston strikes the top of the chisel, transferring energy to the rock. Step 6: Cycle Repeats The valve automatically switches again, raising the piston for the next blow. Simplified Operating Principle The breaker converts: 1. Hydraulic energy(oil pressure from excavator) 2. Into kinetic energy (moving piston) 3. Into impact energy(hammer blow on the chisel) 4. Which fractures the rock through repeated high-energy impacts. Common Wear Parts The parts most frequently replaced are: * Chisel/tool bit * Tool pin * Retaining pin * Front bush * Lower bush * Seal kit * Diaphragm (accumulator) * Side bolts/tie rods These components experience the highest wear due to repeated impacts and vibration.