An attachment hammer is a hydraulically powered impact tool for carrier machines such as excavators, compact loaders or carrier arms. It is used to loosen, break and size concrete and rock. In practice, the attachment hammer is often combined with other tools, for example with concrete demolition shear for selective deconstruction or with hydraulic splitter for low-vibration applications. This creates a methodically coherent interplay for concrete demolition and special demolition, building gutting and cutting, rock demolition and tunnel construction, natural stone extraction as well as special operations.
Definition: What is meant by attachment hammer
An attachment hammer (also hydraulic breaker or excavator attachment hammer) is a hydraulically driven impact device that is supplied with oil flow and pressure via the carrier machine. A piston accelerates cyclically and transfers impulse energy to a tool bit (chisel, pointed or flat tool). As a result, concrete, masonry, rock or asphalt are loosened, fractured or scabbled. Attachment hammers cover a wide performance range, from light tools for building gutting to heavy hammers for primary demolition and secondary demolition in open-pit mining or tunnel heading.
Design and operating principle of attachment hammers
An attachment hammer converts hydraulic energy from the carrier machine into impact energy. Decisive factors are correct matching to the oil flow, the damping and guiding characteristics of the housing, and the interaction between piston, tool holder and chisel. Good coupling to the material is essential, as idle blows lead to wear, noise and loss of efficiency.
Main components
- Housing with noise insulation and vibration damping
- Hydraulic unit with control and return lines, often with hydraulic accumulator
- Impact piston and guide with lubrication
- Tool holder and wear bushings
- Tool/chisel (pointed, flat, round or tamping chisel)
Tool bits and selection
- Pointed chisel for brittle rock, pinpoint starts and crack initiation
- Flat or wide chisel for concrete slabs, removal and edge breaking
- Round or blunt tools for tamping, stripping top layers
- Special tools for thawed frost soil, asphalt or slag
Applications and differentiation from alternative methods
The attachment hammer plays to its strengths where structured impact energy should quickly create fractures. At the same time, there are scenarios in which alternative methods offer technological or environmental impact advantages. In project planning, it is worth taking a combined look at hydraulic impact technology, concrete demolition shear, hydraulic rock and concrete splitters and complementary tools such as combination shears, multi cutters, steel shear and cutting torch.
- Concrete demolition and special demolition: Attachment hammers open components, release thick layers and create predetermined breaking points. For selective separation, biting off reinforced concrete and lower vibrations, concrete demolition shear is a precise complement.
- Building gutting and cutting: In inner-city areas with limits on noise and vibration, low-vibration methods are advantageous. Hydraulic splitter create controlled cracks without impact noise. Metallic inserts and lines are cut with steel shear, multi cutters or a cutting torch.
- Rock excavation and tunnel construction: In heading and during cross-section enlargements, the attachment hammer scores with a fast blow rate. In sensitive zones (vibration limits), splitting methods or rock wedge splitters are an alternative with a well-controllable crack path.
- Natural stone extraction: The hammer is used for coarse exposure and block release. If block quality is to be preserved, hydraulic splitter support low-crack extraction.
- Special operation: In plant areas, near utilities or at listed structures, concrete demolition shear and splitting solutions enable controlled work; the hammer then serves for pre-loosening or removing remaining concrete residues.
Technical parameters and sizing
For efficiency and to protect equipment and structure, sizing is crucial. The goal is a well-matched relationship between carrier machine, hammer and component. Key parameters are impact energy, blow rate, hydraulic pressure, oil flow and tool diameter.
- Carrier machine: typically 1–80 t operating weight; depending on class, oil flow of approx. 20–250 l/min
- Operating pressure: usually 90–180 bar at the hammer (observe manufacturer specifications)
- Impact energy/power: match to element thickness, reinforcement ratio and rock strength
- Tool: diameter and length matched to the guide; monitor the wear pattern
- Hydraulic power units: For stand-alone tools such as hydraulic splitter or rock wedge splitters, external hydraulic power pack provide the required pressure and flow independently of the excavator
Best practices for operation
A material-appropriate working method increases removal performance, reduces emissions and protects the system. Critical are chisel placement, contact time, working angle and avoiding idle blows.
Positioning and chisel guidance
- Work with stable contact pressure; keep the chisel in constant contact
- Working angle just under 90°; at edges, slightly inclined to guide spalling
- Use crack propagation: from the edge to the center, from weak to strong zones
- Avoid idle blows; if no removal occurs, change the starting point
Thermal management and hydraulics
- Keep oil temperature within target; schedule breaks in case of heat build-up
- Monitor filter condition and leakage oil; log pressure and flow rate
- Observe lubrication intervals for the tool guide
Substrate-specific procedures
- Reinforced concrete: first open the cover concrete, expose reinforcement, then separate with concrete demolition shear
- Massive rock: provide drill cuts and predetermined breaking points; alternatively combine splitting technology for defined cracks
- Asphalt/slabs: use wide tools, work off uniform fields
Emissions and immission control
Impact work generates noise, vibrations and dust. In sensitive environments, restrictions may apply. A forward-looking choice of method reduces risks. Hydraulic splitter work very quietly and almost vibration-free; concrete demolition shear reduce structure-borne noise compared to impact work. Dust can be mitigated by water spray, vibrations by shortened impact times, adjusted energy and suitable starting points. Notes from permits and standards must always be observed.
Maintenance, wear and service life
Regular inspections ensure the performance of the attachment hammer and prevent consequential damage. Wear parts such as tool bushings, seals and retaining pins should be replaced based on condition.
Daily checks
- Check tool retention, retaining pins and safeties
- Lubricate the guides; observe grease quality and intervals
- Seal hydraulic connections, repair leaks immediately
- Inspect chisel tip and cross-section for breakouts and mushrooming
Hydraulics and power supply
- Ensure oil cleanliness (filter changes); document pressure/flow
- Check housing and dampers for cracks
- For stand-alone systems, hydraulic power pack supply the energy for hydraulic splitter and rock wedge splitters – protect hose runs and keep couplings clean
Safety and occupational safety
During impact breaking, rock splinters and concrete pieces can fly off. Safety distances, barriers and appropriate personal protective equipment are essential. Maintain line of sight between operator and surroundings; consider hazards from kickback and edge break-offs. When changing tool bits, depressurize and secure against unintended start-up. Legal requirements and operating instructions must always be observed.
Planning and methodological combination
Projects benefit from a coordinated sequence: the attachment hammer opens or loosens; concrete demolition shear separate reinforcement and components selectively; hydraulic splitter or rock wedge splitters create controlled crack patterns in sensitive areas; steel shear, combination shears, multi cutters and a cutting torch handle metallic structures. This allows performance, environmental impact control and component quality to be balanced in a targeted manner.