Cat’s latest mini hydraulic excavators
By Belinda Smart18 November 2021
Cat has introduced two new mini hydraulic excavators that are claimed to offer increased power and performance along with lower operating costs, for the markets of North America, Europe, Australia and New Zealand.
The new 304 and 305 CR models are the final machines to be reengineered to Cat’s “next generation” mini hydraulic excavator design.
The 4-tonne Cat 304, and 5-tonne Cat 305 CR mini hydraulic excavators are designed to “deliver more power to the pumps, higher bucket breakout forces and deeper standard digging depths to increase performance by up to 20% over their E2 series counterparts,” according to Cat.
Features include extended filter service life, common componentry throughout and flat, easy-to-replace side panels. The manufacturer said the units deliver up to 10% lower owner and operating costs.
The 304 machine has a narrow, 1700-mm (66.9-in) track width, 254 mm (10 in) slimmer than its predecssor the 304 E2.
Cat said the design also increases performance, balance and stability in the 4-tonne class model, supported by a reduced radius and extra counterweight option.
Meanwhile the new engine on the 5-tonne class Cat 305 CR “delivers nearly 9% greater power to increase machine performance.”
“Hydraulic system improvements provide higher breakout forces – 49.2 kN (11,061 lbf) bucket, 28.3 kN (6,362 lbf) standard stick and 25.2 kN (5,665 lbf) long stick – to improve digging efficiency in hard rock applications.
“It also offers 140 mm (5.6 in) deeper dig depths than the 305 E2, giving it more application flexibility. Its compact radius swing reduces overhang when working to the side, while its 1980-mm (78-in) track width and new extra counterweight option help to optimise stability and lift performance in confined spaces.”
Both models now feature an angle dozer blade option for flexibility in backfilling and finish grading applications, which offers “ample above- and below-grade travel with standard float function for easy clean-up.”
The blade moves 45 degrees left or right of centre, with movement controlled by the right-hand joystick, while the left joystick handles machine drive.
Interchangeable counterweight packages are on offer, and the Cat Stick Steer System allows the operator to switch from conventional lever/foot-pedal steering controls to low-effort joystick operation. Two travel speed ranges and standard cruise control facilitate moving around the jobsite with minimum operator interaction.
Cat said the turbocharged Cat C1.7 Turbo engine delivers higher power than the previous C2.4 engine and meets U.S. EPA Tier 4 Final and EU Stage V emission standards.
Auto idle, auto engine shutdown and load-sensing hydraulics with a variable displacement pump are designed to lower fuel usage at the site for affordable operation.
Both machines feature a sealed and pressurised cab enclosure with heating and/or air conditioning for all-weather climate control.