Hydraulic Breaker Product

Overview

A hydraulic breaker (also called a hydraulic hammer or percussion breaker) is an excavator-mounted impact tool that reduces rock, concrete, or masonry by rapid percussion. Unlike the crushing force of a grapple or jaw attachment, the breaker delivers a series of precisely timed hammer blows — 800 to 2000 per minute — striking a hardened chisel into the material. Each impact delivers 900–3500 joules of energy, sufficient to fracture granite, reinforced concrete, and cast-in-place foundations. The tool is powered entirely by the host excavator's hydraulic pump and requires no separate motor.

How it works

The breaker is a self-contained hydraulic percussion machine. At its core is a heavy hardened steel Piston Head inside a precision-bored Cylinder Barrel. The piston is driven up and down by alternating hydraulic pressure cycles, and with each downstroke, the Piston Rod strikes the Chisel Tool directly into the rock.

The cycling is managed by a clever Pilot Valve & Control. Inside is a Pilot Spool that senses piston position using pressure feedback. When the excavator operator opens the joystick, the Inlet Manifold ports pressurized oil from the excavator pump into the top of the piston chamber. This drives the piston downward at high speed. As it approaches the bottom of its stroke, a pilot pilot-drain port opens, exhausting pressure from above the piston. Simultaneously, return oil entering the Pilot Valve & Control from the rock penetration backs up and pushes a Check Valve, opening an upper-chamber inlet. The pressure reversal launches the piston upward on the return stroke.

Complicating the design is the need for speed without stalling the excavator pump. A Nitrogen Pre-charge Accumulator, pre-charged at 0.8–1.0 bar nitrogen, plays the critical role. As the piston rises on the return stroke, the accumulator oil chamber expands, pulling oil from the low-pressure return line. This cushions the upstroke, preventing the sudden pressure spike that would shock-load the pump. The stored elastic energy helps lift the piston, reducing the net energy demand on the excavator. Between blows, the accumulator slowly releases this energy, maintaining the piston lift force.

The Pilot Spool and its Spool Spring are tuned so the machine self-cycles at a frequency (typically 800–2000 Hz) determined by the incoming oil pressure. Higher pressure from the excavator pump speeds the cycle; lower pressure slows it. The operator controls impact energy by modulating pump flow and pressure through the joystick. A Pressure Sensor monitors the pressure inside the machine; if it spikes above a set relief (typically 300 bar), a relief valve opens in the Inlet Manifold, protecting the breaker and excavator from overpressure.

The striking end is the Chisel Tool. A hardened steel Chisel Hex Stem (six-sided rod) wedges into a Drive Keyway machined into the piston rod. As the piston drives downward, it forcibly rotates the chisel slightly through the keyway, locking it against bounce-back. The chisel tip — typically a conical Striking Point of tungsten carbide or hardened alloy steel — takes the percussion impact. The conical geometry focuses stress at the tip, allowing efficient fracturing. When the tip dulls or chips after thousands of impacts, it is unscrewed from the hex stem and replaced with a fresh one.

The Piston Ring segmented seal maintains oil tightness as the piston cycles. Guide Bearing bushings at the front and rear support the piston radially without binding. The Main Housing is cast ductile iron, strong enough to withstand the shear forces of impact cycling.

On the excavator, the breaker mounts via a Excavator Mount & Bracket to the stick or coupler. Vibration Bushing elastomer insulators isolate percussion shocks from the excavator frame, reducing operator fatigue and protecting the machine structure. The Hydraulic Hose & Interface brings pressurized oil from the excavator pump through quick-disconnect couplers; return oil flows back to the excavator reservoir. A Accumulator Charge Line allows the operator to periodically recharge the nitrogen pre-charge using a portable Nitrogen Charging Bottle and regulator.

Over time (weeks of heavy use), nitrogen gradually dissolves into the oil. The operator checks accumulator gas pressure with a gauge and recharges when pre-charge drops below 0.6 bar. Without sufficient nitrogen, the accumulator cannot cushion the return stroke, energy consumption rises sharply, and the machine becomes sluggish and prone to stalling the excavator pump.