Classifying a carrier machine into an excavator size class is fundamental for selecting excavator attachments correctly and for planning work processes in demolition, deconstruction, rock cutting/processing or natural stone extraction safely and efficiently. Knowing the excavator size class allows realistic assessment of load-bearing capacity, hydraulic performance and operating limits, enabling tools such as concrete demolition shears or hydraulic rock and concrete splitters from Darda GmbH to be deployed appropriately for the task.
Definition: What is meant by excavator size class
Excavator size class refers to the technical assignment of an excavator to a size and performance category, which is usually based on operating weight, hydraulic performance as well as kinematics and load-bearing capacity. The excavator size class serves as a reference framework for the choice of excavator attachments (adapter size, permissible masses, required oil flow and operating pressure), for the working method (e.g., shearing, splitting, cutting) and for safety assessment on site. It is thus an interface between project planning, equipment logistics and tool selection, for example in concrete demolition, building gutting, rock excavation, tunnel construction or special operations.
Excavator size classes by operating weight and typical use profiles
A practical classification by operating weight with typical use patterns and tools has proven itself. Ranges vary by manufacturer and configuration; the following classes are common in day-to-day work:
Micro and mini excavators (up to approx. 2 t and 2–6 t)
This class is used where access is tight, in existing buildings and on sensitive soils. Small dimensions and low ground pressures are advantages; hydraulic performance is limited. Suitable are compact attachments for precise, low-vibration, low-impact work, especially for building gutting and cutting. Commonly used are light concrete demolition shears, hand-held or excavator-guided rock and concrete splitters (with a hydraulic power pack), and small combination and multi shears for reinforcing steel, sections and utilities.
Compact and midi excavators (approx. 6–12 t)
Compact machines with higher stability and more oil flow enable universal deconstruction, smaller foundation demolition and opening of reinforced-concrete members. They can use both concrete demolition shears for selective concrete demolition and rock wedge splitters or rock and concrete splitters for low-vibration separation. In this class, combination shears and Multi Cutters for mixed materials (reinforcement, pipes, sheets) are also deployed.
Mobile and crawler excavators, medium class (approx. 12–25 t)
This carrier class covers the majority of conventional demolition and deconstruction tasks. It offers sufficient hydraulic reserves for larger concrete demolition shears, Multi Cutters and steel shears, supports robust downsizing and sorting, and tackles demanding components. In concrete demolition and specialized deconstruction, rotating shears are preferred, while in rock excavation high-performance splitting systems are often used to reduce the need for blasting.
Heavy crawler excavators (approx. 25–50 t and above)
Heavy machines are used for massive components, large foundation blocks, heavy reinforcement and production shutdowns. Particularly powerful steel shears, large-dimensioned combination shears, robust concrete demolition shears and special tools such as tank cutters for special operations are used here. In natural stone extraction or tunnel construction, this class can move large volumes and execute splitting operations safely under high loads.
Technical criteria for classification and tool selection
For selecting attachments for the respective excavator size class, the following key parameters are decisive:
- Operating weight and load-bearing capacity: Permissible tool mass, tipping load and stability determine safe use, especially with reach and torque at the boom.
- Hydraulic performance: The tool’s required oil flow and operating pressure must harmonize with the carrier’s pump capacity, return line and allowable back pressure.
- Kinematics: Boom geometry, quick coupler, rotary feedthroughs and hose routing influence freedom of movement, response times and wear.
- Space and access: Door widths, ceiling load capacity, floor build-ups and corridor areas define whether a mini excavator, compact excavator or a heavier carrier machine can be used at all.
- Emission requirements: In interiors and sensitive zones, low-emission solutions and hydraulic power packs for hand- or excavator-guided tools are often sensible.
Aligning excavator size class and Darda GmbH tools
Darda GmbH tools are designed for defined carrier machine ranges. In practical alignment, the manufacturer’s specifications for the tool’s recommended application range (carrier class, mass, oil flow, pressure) are compared with the excavator’s actual data. This ensures that, for example, concrete demolition shears open and close efficiently, rock and concrete splitters are operated with sufficient pressure, and combination shears, Multi Cutters or steel shears work within the permissible load window.
Typical assignments in practice
- Mini excavators: compact concrete demolition shears and light splitting technology for building gutting and selective deconstruction.
- Midi to medium class: larger shears and splitting systems for wall, slab and foundation sections; Multi Cutters for mixed materials.
- Heavy class: large-dimension shears for heavy reinforcement, sections and tanks; tank cutters for special dismantling.
Application areas at a glance and the role of the excavator size class
Concrete demolition and specialized deconstruction
With thick-walled reinforced-concrete members, the power reserves of heavy excavators are advantageous to carry large concrete demolition shears or combination shears. In sensitive environments, a combination of splitting and shearing is often used to reduce noise emissions and vibration.
Building gutting and cutting
In interiors with tight access, mini excavators with light attachments have the edge. Rock and concrete splitters can be supplied flexibly via hydraulic power packs, while compact concrete demolition shears open components in a targeted manner without unnecessarily loading the load-bearing shell.
Rock excavation and tunnel construction
With confined cross-sections and strict vibration limits, rock wedge splitters and splitting tools are preferred. Depending on the excavator size class, the advance can be staged and controlled. Larger crawler excavators increase handling capacity in haulage logistics.
Natural stone extraction
In quarries and natural stone extraction, a suitable excavator size class enables controlled block release by splitting techniques and safe handling. Boom kinematics and load-bearing capacity reserves are decisive for precise positioning of fragments.
Special operations
Special tasks such as dismantling tanks or plants require coordinated combinations of carrier machine, tank cutter and, if necessary, steel shears. Here, the excavator size class must also be considered in terms of safety and stability, for example with increased reach or restricted working pad.
Hydraulics and power supply
The functionality of hydraulic tools depends on the interplay of flow rate, pressure and allowable back pressure. Pump output varies by excavator size class. Where the on-board hydraulics are not suitable or emission constraints apply, Darda hydraulic power units can provide flexible supply for rock and concrete splitters and other tools.
Practical notes
- Check the tool data sheet: required oil flow, working pressure, return-line requirements, permissible tool mass.
- Consider carrier configuration: quick coupler, auxiliary circuit, oil cooler, rotator/rotation unit.
- Monitoring: observe temperature and pressure under load to avoid performance drop and wear.
Work methodology: splitting, shearing, cutting
The excavator size class influences whether force-based or volume-oriented methods are economical. Rock and concrete splitters and rock wedge splitters are suitable for low-vibration separation of compact components or rock. Concrete demolition shears, combination shears and Multi Cutters play to their strengths in targeted opening, downsizing and separating mixed materials. Steel shears and tank cutters are designed for metallic materials and special cutting tasks.
Safety, permits and organizational aspects
The choice of excavator size class affects safety requirements, transport aspects and possible permits. In general: the carrier machine must be approved for the tool mass including rotation unit, adapter and hose bundle. Ground bearing capacities, shoring, safety distance to structures and protection of the surroundings must be planned early. Legal requirements may vary by country, site and activity; when in doubt, consult the relevant standards and regulations.
Logistics and accessibility
- Transport and access: consider width, height, axle loads and possible removal of equipment.
- Working pads: check ground pressure, ceiling load capacity and subbase, especially in interior demolition.
- Free working space: define swing radius, escape routes, utilities and protective measures.
Quality and performance verification in operation
Regardless of the excavator size class, structured start-up checks are recommended: hydraulic function check, leakage inspection, determination of actual cycle times (open/close, splitting stroke), visual inspection of blade or splitting wedge condition, and documentation of parameters. This allows a robust assessment of the suitability of concrete demolition shears or rock and concrete splitters for the planned work steps.
Outlook: efficiency and emissions in the matching excavator size class
With resource conservation and CO₂ reduction in mind, precise alignment of excavator size class, attachment and power supply is becoming increasingly important. Combinations of compact carrier machines, precise splitting technology and demand-driven hydraulic power packs support quiet, low-vibration methods in sensitive environments. For high mass flow and heavy reinforcement, heavier classes with powerful shears and demolition shears remain the first choice—provided the site conditions allow their use.