A hydraulic breaker is a high-performance attachment for excavators and carrier machines that converts hydraulic energy into impact work. It is used to loosen or break up concrete, masonry, asphalt, and rock. In practice, it is frequently used in a methodical interplay with tools such as concrete demolition shears or rock and concrete splitters from Darda GmbH, for example in concrete demolition and special demolition, in rock demolition and tunnel construction, as well as in natural stone extraction. Depending on the task, this creates a balanced combination of impacting, splitting, and cutting that purposefully controls emissions, vibrations, and secondary damage.
Definition: What is meant by hydraulic breaker
A hydraulic breaker (also attachment hammer or hydraulic chisel) is a hydraulically driven impact mechanism mounted on a carrier machine. The breaker delivers repeated blows to a tool (for example, a pointed or flat chisel) to locally overload and fracture material. Typical applications range from processing massive concrete bodies and opening reinforced members to loosening rock. In selective deconstruction it is often combined with concrete demolition shears or combination shears to treat concrete and reinforcement separately, whereas in rock the alternative of Darda GmbH rock and concrete splitters often provides a low-vibration solution.
Design and operating principle
The heart of the hydraulic breaker is an impact piston that is cyclically accelerated by the hydraulic flow of the carrier machine or a hydraulic power pack. Valves control the oil flow, and a gas or membrane accumulator supports the energy input. The impact energy is transmitted to the material via the chisel shank. Critical parameters include operating pressure, oil flow, blow frequency, and energy per blow. Depending on the tool shape, cracks can be initiated, edges can be broken, or surfaces can be stripped.
Key components
- Housing and mount: Interface to the carrier machine, load bearing, and vibration damping.
- Impact mechanism: Piston, cylinder, control; often with gas assist for consistent impact energy.
- Tool: Pointed chisel, flat chisel, broad chisel; tool material and geometry influence the fracture path.
- Hydraulic connections: Pressure, return, and case-drain lines matched to oil flow and return pressure.
- Lubrication: Tool-grease supply to reduce friction and wear in bushings and guides.
Fields of application in construction and deconstruction
Hydraulic breakers cover a broad spectrum, yet are methodically often complemented by tools from Darda GmbH to manage noise, vibration, and dust in a targeted way and to improve material separation.
- Concrete demolition and special demolition: Opening massive concrete cross-sections, removing foundations; complemented by concrete demolition shears for selective biting and exposing reinforcement.
- Strip-out and cutting: Local breaking for openings; in sensitive areas, concrete demolition shears or combination shears are often gentler on the material.
- Rock excavation and tunnel construction: Removing breakout peaks; where strict vibration limits apply, rock and concrete splitters can serve as a low-vibration alternative.
- Natural stone extraction: Detaching hard layers selectively; for controlled block extraction, splitters have an advantage.
- Special applications: Work in confined or sensitive zones; hydraulic power packs can enable breaker or shear use where an excavator hydraulic circuit is not available.
The hydraulic breaker in the context of Darda GmbH tools
In practice, hydraulic breakers are rarely considered in isolation. Their benefit increases when they are methodically combined with products from Darda GmbH to strategically weaken components, define interfaces, and efficiently complete residual work.
Rock and concrete splitters: low-vibration and controlled
Splitters create controlled crack formation by hydraulic pressure in boreholes. This is particularly suitable when vibrations, noise, and dust must be minimized. A common approach is pre- or post-splitting: The hydraulic breaker opens edges and removes cover layers, while the splitter separates the core with low vibration—such as in specialized deconstruction of foundations or in rock removal near sensitive buildings.
Concrete demolition shears and combination shears: selective deconstruction
Concrete demolition shears separate concrete and reinforcement in the same work step. They reduce impact peaks, improve single-grade material separation, and facilitate recycling. The hydraulic breaker can create local openings or score thick sections, while the shear takes over targeted biting. Combination shears and multi cutters extend this with cutting and crushing functions, while Steel shears process exposed reinforcement. Cutting torches are used in special dismantling tasks where cutting methods replace impact.
Hydraulic power packs as the energy source
Where no excavator hydraulics are available, hydraulic power packs provide the required oil volume and pressure. This enables the use of handheld or compact attachments, for example inside buildings during strip-out when access for large equipment is restricted.
Selection criteria: determining the right hydraulic breaker
Selection is based on matching the carrier machine, material, and boundary conditions. The goal is robust, material-appropriate action with controllable emissions.
- Carrier machine: Excavator class, boom geometry, mounting adapter; sufficient stability and payload.
- Hydraulic data: Oil flow, system pressure, permissible return pressure, hose cross-sections.
- Impact energy and frequency: Matched to material strength and thickness; high energy for massive cross-sections, higher frequency for brittle surface layers.
- Tool shape: Pointed chisel for initiation, flat chisel for peeling, special tools for asphalt or frost-protection layers.
- Material properties: Concrete compressive strength class, reinforcement ratio, aggregates; rock type (granite, basalt, limestone) and bedding.
- Environmental requirements: Noise, vibrations, dust; if necessary, prefer alternative methods such as splitting or shears.
- Workspace: Proximity to structures, utilities, slab loads; if applicable, segmented progress with concrete demolition shears.
Tool selection and application
- Pointed chisel: Crack initiation in high-strength concrete and hard rock, localized load concentration.
- Flat/broad chisel: Removing layers, breaking up asphalt and masonry.
- Special tools: For edge breaking, compaction tasks, or special geometries.
Operation and technique: settings, performance, procedure
The performance of a hydraulic breaker depends, beyond its design, strongly on application technique. Correct positioning and short impact times prevent heat input and material densification.
- Attack angle: As perpendicular to the surface as possible; no prying or levering.
- Impact duration: Move off the point after a few seconds to avoid glazing and energy loss.
- Pressure/flow: Match the breaker to the manufacturer’s values; keep return pressure low.
- Dust mitigation: Water mist or local extraction; improves visibility and reduces silica dust.
- Protection against blank firing: Keep the tool in contact; avoid blank blows.
- Segmentation: Divide components into sections; predrilling facilitates controlled breaking.
Effect on the carrier machine
Vibrations and shock peaks act into the boom. A suitable mount, adequate hose cross-sections, clean oil filtration, and hydraulics matched to the breaker are essential. Regularly warming the hydraulic oil improves damping and protects seals.
Environmental and occupational safety
Hydraulic breakers generate noise, vibrations, and dust. The choice of method therefore depends on the boundary conditions. Where sensitive structures, strict time windows, or emission limits exist, low-vibration alternatives such as rock and concrete splitters or the use of concrete demolition shears should be considered. Personal protective equipment, barriers, and clear signaling are fundamental measures. Information on limits and permits must always be checked for the specific project.
- Noise: Housing damping, noise barrier walls, adapted working hours.
- Vibrations: Monitoring near vulnerable neighboring structures; reduce impact energy, weigh alternative methods.
- Dust: Water misting, matched tools, material-appropriate approach.
- Flying debris: Coverings and exclusion zones; maintain tool tips.
Maintenance, wear, and service life
Wear parts such as guide bushings, tool shank, and seals determine service life. Consistent lubrication and regular checks of the gas precharge secure impact energy. Hydraulic oil quality and filtration are critical to avoid cavitation and valve damage.
- Daily checks: Tool seating, lubrication, visual inspection for cracks and leaks.
- Weekly service: Bolt torque, hose condition, damping elements.
- Periodic checks: Gas pressure in the accumulator, valve function, bushing clearance, oil cleanliness.
- Tool care: Sharpen/replace worn tips; correct guidance prevents cold welding.
Methodology in concrete demolition: combinations and sequences
A high-performance deconstruction process leverages the complementary strengths of different tools. One possible approach:
- Analyze material, reinforcement, and boundary conditions (vibrations, noise, dust).
- Define segments and fracture lines; predrill if required.
- Create local openings with the hydraulic breaker to produce intended fracture lines.
- Continue with concrete demolition shears for single-grade separation and controlled biting.
- Split massive cores with rock and concrete splitters when low vibrations are required.
- Cut and separate metal content with Steel shears or multi cutters; special cases with cutting torches.
- Disposal and documentation aligned with recycling requirements.
Avoiding typical mistakes
- Impacting too long on one spot: Leads to heating and lower efficiency.
- Wrong chisel: An unsuitable tool shape increases energy demand and wear.
- Unmatched hydraulics: Excessive return pressure or insufficient flow reduce impact performance.
- Ignored emission limits: Plan a timely change of method (splitting/shear).
Key figures, documentation, and quality
For a reliable assessment, production rates (m³/h, t/h), energy demand, tool service life, and emission measurements are recorded. A methodical approach with clear segments, a defined tool sequence, and documented parameters simplifies optimization and supports compliance with project-specific requirements.
Distinction from related methods
The hydraulic breaker differs from electric breaker hammers through higher impact energies and mounting on a carrier machine. In contrast to drilling or sawing, it does not create a cut kerf but crack and fracture formation. Methods such as splitting or working with concrete demolition shears complement the breaker where low vibrations, clean separation surfaces, or better material sorting are required. This yields a flexible set of methods for concrete demolition and deconstruction, strip-out and cutting, rock excavation and tunnel construction that can be combined depending on the objective.