On duty: the 305D CR,one of Caterpillar's new D Series mini hydraulic excavators
The new 178 Caterpillar D Series mini hydraulic excavators, (303.5D CR, 304D CR, 305D CR and 305.5D CR) are said to be powerful, versatile, compact-radius machines that work comfortably in confined spaces and build on the quality design and reliability of their C Series predecessors (303C CR, 303.5C CR, 304C CR and 305C CR).
With model designations closely reflecting their operating weights (3.5-5.5tonnes), the new machines feature enhanced stability for greater productivity, a redesigned work-tool coupler, load-sensing hydraulics, and engines that meet US EPA Tier-4 Interim and EU Stage-3A emissions regulations.
Models 303.5D CR and 304D CR are zero-tail-swing machines that keep the radius of the upper body within the width of the tracks, while models 305D CR and 305.5D CR are compact-radius machines that limit upper body tail swing over the tracks to 140mm or less. Both designs reduce the machine's operating footprint and simplify the operator's job.
Increased-width undercarriages for the 303.5D CR and 304D CR and heavier counterweights for the 305D CR and 305.5D CR significantly enhance machine stability, allowing increased lift capacity, more effective use of reach and digging forces, increased capability when handling heavy work tools and improved machine balance for operator comfort.
Similar to large excavators, D Series booms feature a curved design for digging flexibility and fabricated box construction for strength and durability. The independent swing boom allows digging next to walls and obstructions, and an optional long digging arm for each model increases digging depth and lift height.
"Enhancing overall capability of the new D Series models is a standard-equipment dozer blade that simplifies backfilling and clean-up chores. A float function allows the blade to follow ground contours with no operator correction. An optional angle-dozer blade, which can be angled 25° to either side, further expands blade versatility," says Caterpillar.
With model designations closely reflecting their operating weights (3.5-5.5tonnes), the new machines feature enhanced stability for greater productivity, a redesigned work-tool coupler, load-sensing hydraulics, and engines that meet US EPA Tier-4 Interim and EU Stage-3A emissions regulations.
Models 303.5D CR and 304D CR are zero-tail-swing machines that keep the radius of the upper body within the width of the tracks, while models 305D CR and 305.5D CR are compact-radius machines that limit upper body tail swing over the tracks to 140mm or less. Both designs reduce the machine's operating footprint and simplify the operator's job.
Increased-width undercarriages for the 303.5D CR and 304D CR and heavier counterweights for the 305D CR and 305.5D CR significantly enhance machine stability, allowing increased lift capacity, more effective use of reach and digging forces, increased capability when handling heavy work tools and improved machine balance for operator comfort.
Similar to large excavators, D Series booms feature a curved design for digging flexibility and fabricated box construction for strength and durability. The independent swing boom allows digging next to walls and obstructions, and an optional long digging arm for each model increases digging depth and lift height.
"Enhancing overall capability of the new D Series models is a standard-equipment dozer blade that simplifies backfilling and clean-up chores. A float function allows the blade to follow ground contours with no operator correction. An optional angle-dozer blade, which can be angled 25° to either side, further expands blade versatility," says Caterpillar.
