Power pack: new mini excavators on show

IRN looks at some of the new mini and midi excavator launches from the Bauma show, starting with Wacker Neuson’s new duel power version of its 803 mini excavator.

With product development in the larger excavator sizes focused on adapting to strict engine emission regulations, it was left to Wacker Neuson to spring a surprise in the mini segment by showing a dual fuel version of its smallest mini excavator, the 803, powered either by its diesel engine or by an external electro-hydraulic power pack.

When using the hydraulic power pack the excavator will be able to operate as normal, but emission free, making it ideal for indoor uses such as demolition work. Wacker Neuson said an extra benefit of the system was the cooling capacity of the power pack that would allow the excavator to carry out demolition for prolonged periods at high temperatures.

The dual fuel model will be available initially as an option on the 803 model, which is a 900 kg class mini excavator, and later also on the 1.4 t 1404 and the new 1.7 t zero tailswing EZ17. The additional cost of the machine is few hundred euros, with users additionally having to buy or rent the dedicated hydraulic power unit (HPU).

The HPU hydraulic supply is integrated via the excavator’s wheel set, which means that the excavator’s rear pivot radius and 360 degree rotation are maintained unrestricted. The company said it was looking at the possibility that the HPU could be used as a conventional power pack for other hydraulic tool operations.

The dual power option will not be available on the mini excavators supplied to Caterpillar through the manufacturing alliance.

Wacker Neuson also used Bauma to fill out its range with the launch of its smallest zero tailswing model in the 1-2 t class, the EZ17. With an operating weight of 1725 kg, the EZ17 is powered by a 13.4 kW Yanmar engine and has a maximum digging depth of 2.33 m and maximum digging radius of 3.9 m.

JCB has been to the fore in promoting fuel savings and lower operating costs of its new machines, but with its latest mini excavators it is a 52 % increase in load holding capacity that is being trumpeted.

Its new 8014, 8016 and 8020 CTS mini excavators – three upgraded models that follow the launch of the 8018 last year - use a new hydraulic valve block that increases the load holding capacities.

Other improvements include a redesigned kingpost that increases digging depths - by 11% on the 8014 and 8016, and by 3% on the 8020 CTS. This new design also reduces swing radius by 4% on the two smaller machines and by 6% on the 8020. Power on all three of the new machines is provided by a 14.2 kW engine.

Like Wacker Neuson, Yanmar Construction Equipment Europe is adding to its short tailswing range with the launch of the 2.6 t SV26, offering what Yanmar describes as the “an excellent compromise between compactness, power, comfort and accessibility.”

The unit, which has an operating weight of 2665 kg, is powered by a three cylinder, 17.4 kW Yanmar diesel engine, which now features an auto-idle system that lowers engine speed after 4 seconds of inaction. Maximum digging depth is 2595 mm and maximum bucket digging force is 2500 kgf.

Another new 2.6 t class zero tailswing mini excavator comes from Hyundai, with the R25Z-9A filling a gap in the company’s range between its R16-9 and R27Z-9 models.

With a Mitsubishi engine, the Korean-made model can be fitted with buckets with a capacity of up to 0.07 m3. A feature of the new machine is long service intervals, including 1000 hours for hydraulic filters and 5000 hours for hydraulic oil. Lubrication intervals have been increased from 50 to 250 operating hours thanks to the use of self-lubricating bushings. The R25Z-9A has a maximum excavation depth of 2420 mm and its boom length is 4480 mm.

Meanwhile, at Bauma the company said it aimed to become the world’s third largest construction equipment manufacturer by 2016. The growth plan includes new production plants, new products and development of new markets. In Europe, it has currently developing in Geel, Belgium, a new European spare parts warehouse and headquarters, to be opened in 2015.

Caterpillar’s latest short tailswing mini excavator is the 1.7 t class 301.7D CR, supplied by Wacker Neuson under the manufacturing alliance between the two.

The new machine – which comes fresh on the heels of three conventional, 1.6 to 2.5 t class minis launched late last year, the 301.7D, 302.2D and 302.4D – has an extending undercarriage as standard, 990 mm wide fully retracted and 1300 mm at full width.

The 301.7D CR can be specified with either standard or optional long stick giving an additional 140 mm dig depth, an extra 114 mm load height and 153 mm more reach at ground level. The machine is powered by a 17.8 kW engine, down-rated to 13.2 kW, and oil change intervals are 500 hours for engine oil and 3000 hours for hydraulic oil.

Transportability is a key feature of Volvo’s new short tailswing mini, the ECR25D, which can be transported with up to three buckets and a hydraulic breaker on a small trailer and still weigh less than 3.5 t, including the trailer, which makes it easy to transport without a special drivers licence in much of Europe.

Fitted with a 15.5 kW engine, the ECR25D only exceeds its track width when equipped with an additional counterweight, meaning that the machine can get extremely close to objects without risk of collision as it swings.

The D-Series range offers a variety of optional quick couplers and a Volvo attachments. Other new D series excavators include the 5.8 t class ECR58D and 8.8 t ECR88D, both also launched at Bauma.

In the midi-size, attracting a lot of interest was Kubota Baumaschinen with its first excavator to use a Kubota Stage IIIB engine.

The new 8 t class KX80-4, which replaces the KX80-3 model, has a Kubota engine using a common rail injection system and diesel particulate filter (DPF). The engine has already been used on Kubota’s agricultural tractors, but this is its first application in a Kubota construction model.

Kubota’s export sales manager Bernard Dewaele told IRN that DPF regeneration will be automatic, with users only prompted if they need to increase engine speed during the process. The operator can also stop regeneration if necessary during working.

The use of the Stage IIIB engine provides fuel efficiency benefits: in ‘Ecomode’ there will be an 18% fuel saving based on the same power output of the ‘dash-3’ model, and savings of 12% will be possible when working in ‘full power’ operation.

All other Kubota excavators are under the 37 kW rating and do not currently require the use of Stage IIIB engines.

Other new midis at Bauma included a 8 t Bobcat and 6 Doosan Infracore excavators. Bobcat is Doosan’s brand for compact equipment, and Doosan concentrates on larger machinery, but there is some overlap at the lower and upper limits of the two ranges.

The 8540 kg operating weight, reduced tailswing E85, shown in prototype at Bauma, is a replacement for the current E80 and is powered by a Yanmar 44.3 kW diesel engine, meeting Stage IIIB emission requirements through the use of exhaust gas recirculation (EGR) and diesel particulate filter (DPF) after-treatment technologies.

The new engine brings immediate benefits over the previous model, says Bobcat, with a 4% increase in power, a 7% improvement in fuel efficiency to 9.76 m³/l, and a 7% increase in bucket digging force to 6.6 t. More efficient hydraulics also lower cycle times by up to 12%.

The Doosan 6 t, reduced tailswing DX62R-3 – also shown as a prototype – replaces the DX60R machine and also offers improvements over its predecessor. These include a “dramatic” 33% increase in hydraulic performance to give a maximum flow rate of 132 l/min.

The digging forces have also been significantly increased - the bucket digging force is now 4.4 t, an increase of more than 7%, and the arm digging force has been raised by a similar level to 2.9 t. The DX62R-3 is powered by a Stage IIIA, 36.2 kW engine.