The carrier machine is the central platform on which attachments for demolition, deconstruction, and rock processing operate. It provides reach, positioning accuracy, and the required energy. Working together with tools such as concrete demolition shears, rock and concrete splitters, combination shears, multi cutters, steel shears, or special tools such as tank cutters, the appropriate carrier machine determines productivity, occupational safety, and preservation of the structure—from strip-out through selective concrete demolition to rock excavation in tunnel construction.
Definition: What is meant by carrier machine
A carrier machine is the machine that mechanically carries attachments and supplies them with energy. Typical carriers are hydraulic excavators (mini, compact, crawler, wheeled), remote-controlled demolition robots, or, in special cases, telehandlers and crane applications with suitable booms. The carrier machine delivers the necessary hydraulic power or uses external hydraulic power packs, ensures stability, and enables precise guidance of tools such as concrete demolition shears, rock splitting cylinders, combination shears, or steel shears. Decisive is the harmonious match of weight, mounting interface, hydraulic pressure/flow rate, and operating environment.
Types and size classes of carrier machines
Carrier machines are selected based on the operating environment and payload. The spectrum ranges from light carriers for interior demolition to heavy demolition excavators for thick reinforced concrete. The selection significantly influences which attachments can be operated economically and safely.
Compact and mini excavators
Compact carriers of roughly 1 to 6 tons operating weight are used in confined areas, for example during strip-out, selective deconstruction, or in existing buildings. They are suitable for small-format concrete demolition shears and light combination and multi tools. Rock and concrete splitters with an external hydraulic power pack can be particularly advantageous in this class when low vibration levels and low-noise working methods are required, for example in sensitive interior environments.
Medium and large demolition excavators
Carrier machines from about 14 tons up to 60 tons and more cover the economic core area of concrete demolition. High-performance concrete demolition shears, combination shears, and steel shears are used here. The higher hydraulic flow as well as the greater stability allow efficient separation of reinforced concrete, pulling of reinforcing steel, and cutting of structural steel sections. For massive components in bridge or industrial demolition work, these carrier classes are the rule.
Demolition robots and remote-controlled carriers
Remote-controlled carrier machines show their strengths where emissions, vibrations, and access are particularly critical—such as in tunnel headings, core zones of industrial plants, or contaminated sites. In combination with compact concrete demolition shears or rock splitting cylinders, precise, controlled demolition can be achieved, often combined with external hydraulic power packs when grid- or battery-based supply is preferable.
Special carriers and mounting points
Depending on the task, telehandlers, special booms, or cranes can serve as carriers, provided that stability, load handling devices, and hydraulic supply are ensured in accordance with standards. This mainly concerns special tools or special operations, for example with tank cutters or custom brackets in narrow shafts.
Hydraulics and power supply
Hydraulics are the key to powerful use of attachments. Pressure, flow, and control technology must match the tool. Concrete demolition shears and combination shears generally require double-acting circuits with sufficient flow; rock splitting cylinders often operate with high-pressure impulses generated by a suitable hydraulic power pack.
Control and hydraulic circuits
- Pressure level: tool-specific, often in the range of high system pressures in demolition. The permissible working pressure of the tool must not be exceeded.
- Flow rate: determines working speed (open/close, splitting cycle). Too little flow leads to low cycle rates; too much can promote heat and wear.
- Return and case drain: tools with rotators or hydraulic motors require suitable returns and, if necessary, case drain lines.
- Control logic: proportional or on/off; smooth actuation supports precise positioning, for example when cutting reinforcing steel.
Hydraulic power packs as external supply
If no suitable auxiliary circuit is available on the carrier machine or the task requires low-noise, low-emission work, external hydraulic power packs are used. This is particularly sensible with rock and concrete splitters as well as with handheld cutting or separating tools. A suitable power pack from Darda GmbH provides the pressure and flow values required for the respective cylinders and shears and thus enables safe and efficient operation—even independent of an excavator’s on-board hydraulic system.
Mounting, adapters, and quick couplers
The interface between carrier machine and attachment determines assembly time, safety, and load distribution. Quick couplers reduce setup times; rigid mountings or adapter plates offer maximum stability and exact force transmission.
Fit and load path
- Tool-specific mounting dimensions (pin spacings, widths, diameters) must harmonize with the boom or quick coupler.
- The load path should be selected to minimize transverse and torsional loads. This protects pin bearings and the tool frame.
- Rotators and rotation units increase flexibility, but require correct hydraulic hose routing and case drain handling.
Locking and inspection
Locking systems must be checked before each use. Mislocking leads to hazardous situations and can damage the tool and carrier. Visual and pull checks, as well as regular inspections of the locking mechanism, are mandatory.
Stability, load capacity, and reach
The interplay of carrier weight, boom geometry, and tool mass determines stability. Especially at large outreaches and when working over an edge (e.g., at slabs or slopes), the carrier’s load capacity must be reconciled with the tool and load case.
- Tool-to-weight ratio: For concrete demolition shears and steel shears, minimum carrier classes are advisable to ensure performance reserves and stability.
- Center of gravity: Rotators and long tools increase the lever arm. A low center of gravity on the carrier improves stability.
- Ground conditions: Check bearing capacity of the ground and support; in buildings, slab loads and shear forces must be considered.
Carrier machine by application area
Concrete demolition and special deconstruction
In concrete demolition and special deconstruction, medium to large excavators with concrete demolition shears, combination shears, and steel shears have proven themselves. With highly reinforced components, powerful shears accelerate material throughput. For controlled partial deconstruction, for example near sensitive facilities, rock and concrete splitters are advantageous because they work with low vibration levels.
Strip-out and cutting
During strip-out, compact carriers as well as handheld solutions are used. Multi cutters and smaller combination shears cut profiles, cable ducts, or thin-walled structural steels. Tank cutters are operated—depending on design—by hand via a hydraulic power pack or guided on brackets when a carrier machine is required for reach and positioning.
Rock demolition and tunnel construction
In rock, controlled splitting technology is central. Carrier machines with high positioning accuracy in combination with rock splitting cylinders and suitable power packs enable fracture-safe, low-vibration removal. In tunnel tubes or adits, where ventilation and emissions are limited, remote-controlled carriers offer advantages. Concrete demolition shears are used in the fit-out to adapt linings or in the deconstruction of temporary concrete components.
Natural stone extraction
For primary extraction, precise split lines are required. Carriers with stable support and fine hydraulic control guide rock and concrete splitters as well as rock splitting cylinders along the planned fracture lines. The low vibration levels protect the existing structure and reduce crack formation.
Special operations
Special tasks—such as in explosion-hazard areas (ATEX zones), in contaminated plants, or during tank dismantling—often require a combination of a remote-controlled carrier machine, a shielded work area, and external power packs. Tools such as tank cutters or specially configured shears are selected so that ignition sources are minimized and material properties are taken into account.
Selection criteria for the suitable carrier machine
- Component and material: concrete strength, degree of reinforcement, steel grades, natural stone structure.
- Accessibility: room height, door widths, load-bearing capacity of the floor slab, escape routes.
- Performance data: required hydraulic pressure/flow, tool weight, necessary additional functions (rotation, crush protection).
- Environment: noise control, vibration limits, emissions, dust management.
- Logistics: transport width/height, setup times with quick coupler, energy supply via on-board hydraulics or external hydraulic power pack.
- Safety: stability, visibility, emergency stop, remote-controlled options.
Operation, safety, and organization
Safe procedures rely on competent personnel, intact equipment, and clear communication. In general: do not exceed load and operating limits of the carrier, check lockings, secure hydraulic lines, and cordon off hazard zones. In sensitive environments, low-vibration methods—such as with rock and concrete splitters—are often advantageous. Legal requirements and safety regulations must be observed; implementation is project-specific and responsible.
Maintenance, wear, and availability
Regular maintenance increases readiness for operation and reduces life-cycle costs. This includes:
- Lubrication and visual checks on pin bearings, boom, and mountings.
- Hydraulic care: oil condition, filter changes, leak-tightness checks, case drain quantities.
- Wear parts on the attachment: blades, jaws, cylinder guides, and rotation units.
- Documentation: inspection intervals, maintenance history, retrofits.
Where on-board hydraulic limits are reached, splitting tasks between the carrier machine and an external hydraulic power pack can increase the availability of the entire unit.
Technical matching of carrier machine and tool
Performance unfolds from the right setup. Good practice is clear parameterization and alignment of limits.
- Tool-to-carrier ratio: the tool weight should match the carrier’s class, including rotator and adapter.
- Hydraulic operating window: keep working pressure and flow within the permissible ranges of the tool.
- Setup states: consider the quick coupler (additional build height, weight, possible play).
- Operating scenario: continuous duty vs. cyclic duty; consider heat balance and cooling capacity.
Role understanding: the carrier machine as a system platform
The carrier machine is not an isolated machine but a system platform for specialized tools from Darda GmbH. It combines mechanics, hydraulics, and operation into a single unit. Whether a concrete demolition shear in bridge deconstruction, a rock splitting cylinder in a tunnel, or a tank cutter in a special operation—the coordinated combination of carrier, attachment, and energy supply enables controlled, efficient, and structure-preserving work.