Demolition breakers are tools designed for demolition and fragmentation of concrete, mortar, asphalt and rock. Their performance is directly related to impact energy, blow frequency and efficiency of force transfer to the substrate.
1. Operating Principle
The breaker operates through an electromechanical or pneumatic system that converts electrical energy or compressed air into high-intensity reciprocating motion. This motion produces successive impacts transmitted to the chisel or bit.
2. Impact Energy (Joules)
Impact energy, measured in joules (J), indicates the force applied per blow. Professional equipment typically ranges from:
- 5–15 J → light removal (coatings and small openings);
- 15–30 J → medium demolition (floors and thin slabs);
- 30–70 J → structural demolition and reinforced concrete;
- > 70 J → heavy applications and thick pavement.
Higher energy reduces demolition time but increases vibration and equipment structural stress.
3. Blow Frequency (BPM)
Blows per minute (BPM) affect productivity. There is a technical trade-off between energy and frequency:
- High energy → lower frequency;
- Low energy → higher frequency.
The ideal combination depends on material compressive strength (e.g. fck for concrete).
4. Shank Systems
- SDS Plus: light applications;
- SDS Max: medium applications;
- Hexagonal (28 mm / 30 mm): heavy applications.
The shank system must withstand the torque and energy transmitted without deformation.
5. Vibration and Ergonomics
Breakers produce significant vibration (m/s²), which can cause fatigue and occupational risk. Professional models include:
- Anti-vibration systems (AVS);
- Impact-absorbing handles;
- Reinforced metal alloy housing.
6. Specification Criteria
- Type of material to be demolished;
- Substrate thickness and strength;
- Power availability (220V, 110V or compressor);
- Daily operating time;
- Environment (indoor/outdoor).
Technical Conclusion
Breaker selection should consider impact energy, blow frequency and structural robustness. Undersized equipment increases job time; oversized units increase operating cost and operator fatigue. Correct technical choice optimizes productivity and safety.
