BOBCAT has launched its new-generation mini-excavators in the four- to six-tonne category, which have been designed to provide exceptional performance levels.

The E45 and E50 zero tail swing (ZTS) mini-excavators are intended for applications in construction, demolition, rental, utility, landscaping and other works in different geographic markets.

“Both excavators offer fast work cycles with smooth and precise workgroup functions, superior operator comfort, reduced noise, excellent service access and increased reliability and stability,” says a spokesman for Bobcat.

Both the excavators are based on the same platform. Equipped with cab and bucket, the E45 and the E50 have an operating weight of 4,634 kg and 4,905 kg and a maximum digging depth of 3,300 mm and 3,524 mm, respectively.

They are powered by the four-cylinder, Kubota V2403-M-DI-TE38-BC-5 and V2403-M-DI-TE38-BC-4 turbo-charged Tier III diesel engines, respectively, producing 30.2 kW and 35.4 kW net per SAE J1349 of output power at 2,200 rpm. This results in breakout forces of 28.0 kN in the dipper arm and 35.1 kN at the bucket for the E45 and 30.4 kN in the dipper arm and 41.2 kN at the bucket for the E50 and lifting capacities of 2,369 kg and 2,778 kg, respectively, at ground level and at a radius of 3 m.

The E45 and E50 have as standard an ‘auto-idle’ feature, which reduces fuel consumption and noise and creates a more comfortable environment. “The auto-idle feature, which can be enabled at the operator’s discretion, automatically causes the engine to drop to idle if the excavator functions are not used for a period of about four seconds. The engine automatically returns to the pre-set throttle position when the operator moves a joystick or a travel function,” says the spokesman.

In addition, the engine, air intake, cooling and exhaust systems, along with the hydraulic pump and valve, are designed to offer a lower bystander noise (95 LwA for the E45 and 96 LwA for the E50) and operator ear noise level (79 and 81 dB(A) respectively), both class-leading values for the four- to six-tonne mini-excavator class, the spokesman claims.

The E45 and E50 are also packed with features for operator comfort. A completely new cab design offers the operator plenty of space for the feet and legs as well as a comfortable work environment. The cab also offers 360-degree visibility to the right track as well as to the rear of the cab. The wiper motor is mounted on the lower front window to provide superior visibility to the front.

The directional lug rubber tracks, meanwhile, provide a smooth ride with less vibration without reducing surface grip. Sealed floor plates and the routing of the hydraulic hoses below the floor mat isolate the operator from undesired heat in the cab.

“The new Bobcats are designed to achieve the highest performance with exceptionally smooth movements, combining maximum productivity with the ability to carry out jobs with precision and fingertip control.

“The load-sensing piston pump and the closed centre valve enable exceptionally fine metering of hydraulic flow for smooth, precise control of machine functions, even with simultaneous operations, while reducing reaction time, hydraulic noise, and fuel consumption,” says the spokesman.

The high hydraulic flow (75.7 l/min) in the auxiliary line, in combination with the excellent stability, has increased the range of attachments that can be used on these excavators, increasing speed and versatility for performing a wider range of tasks.

The undercarriage on the E45 and E50 features sealed, maintenance-free track rollers, a top roller and wide sprockets offering high resilience and a long service life. The ‘open’ design and sloped surfaces of the X-frame undercarriage help prevent the build-up of mud and debris, he says.

The design of the hydraulic components, routing of the hydraulic hoses and hydraulic connections, combined with improved assembly procedures, significantly reduces the possibility of hydraulic leaks and increases quality and reliability. ‘Quicklock’ snap-to-connect fittings for connections to the valve block ports lowers stress on the fittings as they exit the valve, reducing the chance of leaks.

In terms of serviceability, access through the wide opening tailgate and sidegate simplifies routine maintenance. “There is easy access to all service components such as filters, the battery and radiator as well as centralised grease points. The air-conditioning condenser and hydraulic cooler can be easily separated for cleaning purposes, without need for tools,” says the spokesman.

The E45 and E50 also offer the protection of an electronically-controlled engine and hydraulic system monitor with automatic shutdown.

“Importantly, Bobcat excavators are known for their reliability, a key factor contributing to the low overall lifetime operating cost of a Bobcat excavator. CAD techniques, endurance testing of components and assemblies under extreme conditions, and highly durable materials are used to ensure reliability,” concludes the spokesman.