A crawler undercarriage is the load-bearing base of numerous construction machines and mobile carrier machines used in concrete demolition, special demolition, rock excavation, tunnel construction, and natural stone extraction. Thanks to the large-area footprint of the tracks, a crawler undercarriage provides high traction, low ground pressure, and stability on uneven, slippery, or sensitive ground. In combination with hydraulic attachments from Darda GmbH—such as concrete demolition shear, hydraulic rock and concrete splitters, combination shears, multi cutters, or steel shear—the crawler undercarriage forms the foundation for precise, low-vibration, and controlled work under demanding conditions.
Definition: What is meant by crawler undercarriage
A crawler undercarriage is an undercarriage with two endless track chains (steel or rubber tracks) that run over drive sprockets, idlers, carrier and track rollers, as well as track guides. The drive is usually hydrostatic, with steering via different rotational speeds of the left and right track. Such a crawler undercarriage distributes mass evenly, reduces ground contact pressure, and increases stability. In interaction with hydraulically powered tools—such as concrete demolition shear, rock wedge splitter, or tank cutters—it enables productive work where wheeled undercarriages reach their limits.
Design and operating principle of a crawler undercarriage
The core system consists of the track frames, track chains, track and carrier rollers, support rollers, idler with tensioning device, and the drive sprocket. Depending on the application, the track is designed as a robust steel track with individual shoes or as an elastic rubber track. Power is transmitted from the drive sprocket to the track links. Steering and turning on the spot (small turning radius up to rotation about the vertical axis) are possible through differential track speeds. The combination of a large footprint and low center of gravity ensures secure working positions—an essential advantage for precise cutting and splitting operations.
Steel vs rubber tracks
Steel tracks offer high wear resistance, directional stability, and traction on abrasive surfaces such as concrete, rock, or gravel. Rubber tracks reduce vibration and ground damage, are quieter, and are suitable for indoor areas or sensitive grounds. For work with hydraulic splitter on natural stone and in quarries, steel tracks are often advantageous, while for strip-out and cutting operations in existing buildings, rubber tracks protect the substrate.
Undercarriage width, ground clearance, and support area
Wider tracks and longer ground contact increase stability, while ground clearance facilitates overcoming obstacles. An adapted track gauge and track width are important when working with booms and heavy tools—such as concrete demolition shear or combination shears—to improve the tipping safety factor.
Use in concrete demolition and special demolition
In the deconstruction of reinforced concrete structures, precise positioning is as important as controlled material removal. A crawler undercarriage enables sensitive approach to components, safe work on slabs or ramps, and holding the tool in the optimal position. With concrete demolition shear, components can be separated with low noise and vibration. The stable base of the crawler undercarriage limits unwanted oscillations and supports clean separation joints. In highly sensitive areas—such as special demolition during ongoing operations—compact crawler undercarriages with electric power supply are particularly suitable.
Strip-out and cutting
In strip-out operations in existing buildings, low emissions and compact dimensions are crucial. Crawler-mounted carrier machines can be operated with external hydraulic power units to reduce the burden from exhaust and noise. In combination with multi cutters or combination shears, lines, rebar, and lightweight components can be disconnected in a controlled manner. The crawler undercarriage enables safe maneuvering in confined corridors and on load-bearing intermediate slabs.
Rock excavation, tunnel construction, and natural stone extraction
In rock and underground work (see rock demolition and tunnel construction), the terrain topology demands a secure footprint with simultaneously low ground pressure. A crawler undercarriage adapts to rough ground and holds position when controlled stresses are applied to rock or concrete components using hydraulic splitter, rock wedge splitter, or concrete demolition shear. Especially in tunnel construction, advance, positioning accuracy, and a calm machine are important to keep crack patterns predictable and protect surrounding structures.
Hydraulics and power supply on the crawler undercarriage
Crawler-mounted carrier machines provide hydraulic power for attachments or use external hydraulic power pack. Important parameters include pressure, flow rate, tank return, and drain line to ensure efficient, cavitation-free operation. Organized hose management and protected lines are mandatory—especially when working with sharp-edged demolition materials and in dust-laden environments.
Performance parameters for concrete demolition shear and splitters
Decisive factors are the required operating pressure and a stable flow rate so that concrete demolition shear can develop its cutting force and hydraulic splitter can build the necessary splitting pressure. Return lines should be generously sized and low-pressure. For external power packs, the rule is: hose lengths as short as possible and only as long as necessary—to minimize pressure losses.
Selection criteria for the appropriate crawler undercarriage
The selection is based on the application, site-specific boundary conditions, and the tools to be mounted. The interaction of operating weight, reach, ground conditions, and the required level of precision is decisive.
- Load capacity and stability in relation to attachments such as concrete demolition shear, combination shears, or steel shear
- Track width, track length, and track gauge for low ground contact pressure and tipping stability
- Drive and power concept: diesel-hydraulic, electric with hydraulic power pack, or hybrid
- Transport width, clearance height, total mass, and load distribution (special considerations for work on slabs)
- Ground protection: rubber or steel tracks, protective pads, mats
- Dust, noise, and exhaust requirements—especially for indoor work and in tunnels
- Maintenance accessibility, hose routing, guards, and service intervals
Safety, ergonomics, and operation
Working with crawler undercarriages requires thorough instruction, anticipatory driving, and coordinated site logistics. Slopes, edge loads, and load-bearing capacities should be evaluated conservatively. Safety distances during splitting and cutting must be observed, especially when stresses are released or components may yield unpredictably. Personal protective equipment, machine safety devices, and a structured emergency concept are obligatory. Legal requirements may vary by country and application and should be observed in general.
Environmental influences and ground protection
A crawler undercarriage distributes loads over a large area, reduces rutting, and protects sensitive surfaces. Nevertheless, support plates, mats, or protective layers are advisable to preserve coverings and waterproofing. Oil management, leak checks, and dust suppression—such as by misting or adapted work methods—serve environmental protection. For indoor areas and tunnels, electrically powered carriers with external hydraulic power pack are gaining importance to keep emissions low.
Maintenance, wear, and service life
Dust, splinters, and abrasive fines from concrete and rock accelerate wear. Regular cleaning and inspection of tracks, rollers, seals, and tensioning systems increase availability. Track tension and alignment should be checked to avoid uneven wear. Guards and line routing should be intact so that hydraulic components of concrete demolition shear, hydraulic splitter, and other tools are reliably supplied. Wear parts should be replaced based on condition.
Transport, logistics, and site organization
Transport height and width, lashing points, and ramp angles must match the crawler undercarriage. On site, delivery routes, slab loads, and surface loads must be considered. In buildings, protective boards and load-distribution plates help. Clear routing minimizes maneuvering, shortens cycle times, and increases safety—especially important on confined projects such as strip-out.
Typical key figures and terms
Key parameters include ground contact pressure, gradeability, ground clearance, track gauge, track length on the ground, and travel speed. For demolition and splitting work, tipping stability in the working direction also matters; it can be improved with wider tracks, appropriate ballasting, and a matched boom geometry.
Compatibility with Darda GmbH attachments
The combination of crawler undercarriage and hydraulic tools requires matched interfaces. These include coupling systems, hydraulic connections, return lines, and a coherent performance window. concrete demolition shear benefit from stable carriers with sensitive hydraulics. hydraulic splitter and rock wedge splitter require secure positioning and controlled pressure build-up. Multi cutters, combination shears, steel shear, and tank cutters place additional demands on hydraulic performance, hose protection, and stability—particularly for cuts in heavily reinforced zones or during tank deconstruction.
Examples of practical configurations
- Compact crawler undercarriage with rubber tracks and external power supply for interior deconstruction with concrete demolition shear
- Medium carrier class with steel tracks and wide gauge for precise splitting in rock with hydraulic splitter
- Crawler-mounted carrier in a tunnel with adapted lighting concept, dust protection, and robust hose management for combination shears and multi cutters
Planning and risk assessment
Before starting, record ground conditions, load-bearing capacity, slopes, obstacles, and escape routes. Working areas are clearly marked and load cases set conservatively. For splitting and cutting, plan run-out zones and retreat options. General legal requirements for occupational safety, emissions, and disposal must be observed; concrete interpretation may vary regionally.
Future trends for the crawler undercarriage
Electrified carriers with external hydraulic power pack, energy-efficient drives, telematic condition monitoring, and improved damping concepts increase efficiency and precision. Advances in track links, seals, and coatings reduce wear in the abrasive environments of concrete demolition, rock excavation, and tunnel construction. Automated assistance functions for leveling and driving dynamics support safe positioning—a sensible basis for fine interventions with concrete demolition shear and for controlled splitting in natural stone.