Machine Matters

|  December 05, 2010 |

Compact confusion or plentiful choice?

Both. Some manufacturers may call all smaller excavators “compacts”, but regardless there are tremendous options available for equipment buyers

By Mike Anderson

It’s challenging enough to get a handle on the compact excavators available in the marketplace, given the explosion of players in that space over the past generation. What was not that long ago a niche product type in North America served by a few dominant brands offering a few models each is today overflowing with more than two dozen brands producing more than 150 different models – even more depending on how you define compact excavators.

The in-track swing frame on Bobcat’s new E50 compact excavator is designed to keep swing castings and cylinders within the width of the tracks when digging in an offset position. Integrated slew brakes hold loads still and steady on slopes for more accurate load placement.

And therein lies the core challenge: While some equipment manufacturers hold disciplined to the machine type’s 6.0-metric-ton upper weight limit as defined by the Association of Equipment Manufacturers (AEM), there are plenty churning out and marketing “compact excavators” or “mini-excavators” in excess of the 13,228-pound threshold. In some cases, such as the 13,556-pound Bobcat E60 or the likewise new 13,653-pound John Deere 60D and Hitachi ZX60USB-3, it’s a matter of rounding down the designation to the closest metric ton (6.0). In other cases, it’s not even close, in part perhaps because manufacturers such as Gehl and its brother brand Mustang do not make large equipment. Thus, those brands group and market all of their excavators, even their 25,397-pound or 11.5-metric-ton machines, as “compacts.”

Regardless, for the accompanying product round-up of the compact excavator market, we are sticking to the 6.0-metric-ton or 13,228-pound maximum weight, focusing specifically on contributing companies’ machines at the top end of the range, from 5.0 metric tons (11,023 pounds) and up. Absent from the round-up are some leading excavator manufacturers that have models weighing in at just shy of 5.0 metric tons, but with nomenclature that reflects a rounding off to 5.0 metric tons. Examples of such models include the Bobcat E50, John Deere 50D, Hitachi Zaxis 50U-3, Case CX50B and Kobelco 50SR Acera.

More than a digging machine

“A compact excavator is really a multi-function tool carrier – even more than just a digging machine,” says Reece Norwood, Kobelco marketing manager. “Equipped with proportional control auxiliary hydraulics, the machine can be used with hammers, compactors, shears, augers and tilting buckets, to mention but a few of the wide variety of attachments to perform the complete job.”

Easily adjusted via buttons located on top of the blade control lever, a blade capable of angling up to 25 degrees left or right provides the Hitachi Zaxis 50U-3 compact excavator with backfilling efficiencies. The same feature is available on the corresponding John Deere excavator, the 50D.

Trying to set itself apart from the myriad OEMs offering full lines of construction equipment, Kobelco “is the excavator specialist,” says Norwood. “As compact excavators have become more plentiful in today’s market, many manufacturers have treated them almost as a commodity – producing machines that are built purely for cost and do not last. Kobelco machines are built with durability to last.”

On the other hand, says Curtis Goettel, marketing manager, Case Construction Equipment, “with Case’s complete lineup of construction equipment, chances are the contractor is already doing business with a Case dealer. From a contractor’s point of view, it only makes sense to work with the same dealer for your mini-ex as you do for your skid steer, backhoe or dozer.”

One thing manufacturers agree on is the need to provide equipment users with simple maintenance requirements, including ground-level access and longer service intervals. “Maintenance that is easy to do normally gets done,” says Goettel. Says Armando Najera, product manager with full-line manufacturer Komatsu: “Simple and quick serviceability allows maintenance to be completed fast while ensuring it gets completed to extend the life of the machine. A maintained machine is a working machine.”

Hitachi and John Deere compact excavators feature a zero tail swing which, reports Deere product marketing manager Mark Wall, “means less damage to the machine, less chance of damage to surrounding property and increased production, as the operator is free to concentrate on the business end of the machine.” On the Hitachi ZX50U-3 and Deere 50D models, a blade capable of 25 degrees angle left or right was added in response to customers who have asked for more versatility and increased production, says Wall. “It no longer matters whether the material is on the left or the right side of the trench,” he explains, “and the operator doesn’t have to waste valuable production time repositioning the excavator to be at a right angle to the trench.” In addition, the auxiliary hydraulic control has been moved from the floor to the right-hand pilot control lever for easier, more instinctive control.

Case recently updated all compact excavator models to expand the degree of boom swing and reduce the front corner overhang, says Goettel. Case also repositioned the auxiliary hydraulics on the boom to make them easier to use.

With the continued introduction of M-Series models, Bobcat has expanded its compact excavator offering to a total of nine models (excluding the E60 that just surpasses the 6.0-metric-ton operating weight). Features offered on current-generation Bobcat excavators include auto idle, auto shift, fingertip boom control swing, in-track swing frame, pilot-controlled functions and load-sensing, torque-limiting piston pumps. A second auxiliary hydraulic circuit is available as an option for the excavators, which are designed alongside a full line of Bobcat attachments to be “truly attachment-friendly and attachment-ready,” the company says. M-Series excavators come standard-equipped with the X-Change quick-attach system, auxiliary hydraulic lines with quick couplers, and clamp cylinder mounts.

Efficient production

The choice of brands, models, configurations, features and options for compact excavators has grown perhaps as no other over the past generation. As with all construction equipment, however, the ultimate value comes down to the ability to efficiently achieve production.

“Volvo compact excavators have well-designed cabs and ergonomics, smooth control of the bucket through the pilot control load-sensing hydraulics,” says John Comrie, compact product competency manager, Volvo Construction Equipment, “and well-matched breakout force and tear-out force allow easy filling of the bucket in the hardest conditions. There is no point to having a high breakout force and low tear-out force.” Features such as engine return-to-idle and automatic downshift for two-speed travel remove operating tasks for inexperienced operators, says Comrie.

“Our compact excavators are built to some of the same standards as our larger excavators. They are built for the construction market to withstand some of the toughest jobs,” reports Caterpillar. Late this year, Caterpillar introduced its new D-Series models, renumbered to reflect actual operating weights. EW

8055

• 34.1 net horsepower

• 5.29 metric tons operating weight

• 12’4” maximum dig depth

• 9,486 pounds bucket digging force

Double-acting hydraulic “pipework” on all models from the smallest 8008 up, including the 5.29-metric-ton 8055, suits JCB compact excavators for attachment use. This, says the company, is enhanced by both the inclusion of quick-release couplers and a carrier design that provides maximum visibility to the work area, thanks to a narrow boom and dipper, and large front, side and top glass areas. A fully-welded X-frame provides a rigid structure and minimizes dirt build-up, says JCB, which uses sealed-for-life track components and designed its dozer blade to roll material away instead of building it up. “Auto-kickdown” tracking automatically changes the driveline gear to suit the working conditions, says JCB. For maintenance needs, side gull-wing door simplify access to engine and hydraulics components.

YANMAR

ViO55-5B

• 39.5 net horsepower

• 5.23 metric tons operating weight

• 13’1” maximum dig depth

• 7,598 pounds bucket digging force

Almost two decades ago, Yanmar launched the zero-tail-swing excavator, designing the ViO Series so that no part of the excavator’s swing housing extends beyond the tracks. Now into its fifth generation, the ViO Series including the 5.23-metric-ton ViO55-5B model features the VICTAS (ViO Crawler Technology for Advanced Stability) offset track technology. For fast, smooth performance even when combining boom, arm bucket and swing functions, ViO Series excavators use multiple load-sensing, variable-displacement piston and gear pumps, in combination with Yanmar’s hydraulic circuitry design. The standard hydraulic coupler expands the versatility of ViO Series machines by allowing a variety of buckets and other attachments to be used. Cylinder rods on the boom, arm and bucket are protected by spring steel guards.

KUBOTA

KX057-4

KX161-3S

• 43.8 net horsepower

• 5.24 metric tons operating weight

• 12’7” maximum dig depth

• 11,118 pounds bucket digging force

U55 (new)

• 45.4 net horsepower

• 5.38 metric tons operating weight

• 11’10” maximum dig depth

• 11,177 pounds bucket digging force

KX057-4 (new)

• 45.4 net horsepower

• 5.51 metric tons operating weight

• 12’8” maximum dig depth

• 11,177 pounds bucket digging force

The newest compact excavator offerings from industry pioneer Kubota collectively offer a tight- and conventional-tail-swing model option in the 5.0- to 6.0-metric-ton class. The U55, with a tail swing overhang of 2.5 inches, is equipped with a medium-length arm and enhanced arm crowd force, for power in confined areas, says Kubota. Also powered by the 45.4-net-horsepower Kubota engine, the new KX057-4’s conventional configuration lends itself to increased stability in open areas, says the company. The large operator’s station has a wide door, easy-to-reach controls and a new digital display panel. A hydraulic angle blade version is available for each of the Kubota models in this size range, including the established KX161-3S.

GEHL

603

• 57 net horsepower

• 5.705 metric tons operating weight

• 12’7” maximum dig depth

• 8,296 pounds bucket digging force

Compact equipment manufacturer Gehl offers families of conventional and zero-tail-swing excavators beginning at 1.7 and 2.67 metric tons respectively, both configurations moving beyond the 6.0-metric-ton maximum defining the compact category. Gehl excavators, including the conventional 5.705-metric-ton 603 model, feature standard auxiliary hydraulic lines with couplers, precision-fit components, and strong one-piece booms without weld seams or skin plating, the company says. Some models have expandable undercarriages and upper structure leveling for maneuvering and operating in tight, uneven spaces without the need to bench or backfill. An optional long arm and steel tracks are available on most units.

TEREX

TC50

• 36 net horsepower

• 5.02 metric tons operating weight

• 12’1” maximum dig depth

• 7,020 pounds bucket digging force

TC60

• 43 net horsepower

• 5.65 metric tons operating weight

• 12’3” maximum dig depth

• 9,000 pounds bucket digging force

Top-mounted boom cylinders suit Terex compact excavators for demolition and landscaping applications, where large, heavy materials can be moved without damaging the cylinders. Inverse cylinder mounting, with the seal facing down, additionally prevents dirt build-up. The use of spherical bearings ensures energy from torsional movement of the boom is not transferred to the cylinder. The linkage on the Terex compacts is more flush with the tracks compared with other machines, says the company. Linkage that extends out further not only is more susceptible to damage, but can reduce or negate the benefits of zero-turn-swing technology, Terex explains.

WACKER NEUSON

50Z3

• 37.7 net horsepower

• 5.15 metric tons operating weight

• 11’6” maximum dig depth

• 7,599 pounds bucket digging force

6003 (new)

• 58.6 net horsepower

• 5.83 metric tons operating weight

• 12’7” maximum dig depth

• 8,925 pounds bucket digging force

Having introduced its excavators in 2008, Wacker Neuson has moved quickly to expand that line, now offering a rubber-tracked, minimum-swing-radius model running right up against 6.0 metric tons. The two-speed-drive 6003, one of two new compact models introduced by the company in 2010, fills a gap in the Wacker Neuson excavator line between the established 5.0-ton-plus 50Z3 zero-tail-swing model and the 8-ton 8003. Hydraulic features integrated into the machine include auxiliary balance control for driving straight ahead, triple-circuit control and balanced driving pedals. The 6003 comes with a control pattern selector valve, dozer blade and boom-mounted working light. A large cab tilts to the side for easy access to the hydraulic rotary transmission, control block and standard air conditioning unit.

 

CATERPILLAR

305D CR (new)

• 42 net horsepower

• 5.2 metric tons operating weight

• 12’1” maximum dig depth

• 10,050 pounds bucket digging force

305C CR

• 47 net horsepower

• 5.2 metric tons operating weight

• 12’9” maximum dig depth

• 11,442 pounds bucket digging force

305.5D CR (new)

• 47 net horsepower

• 5.5 metric tons operating weight

• 12’9” maximum dig depth

• 11,445 pounds bucket digging force

As part of a D-Series update in late 2010, the designations on Caterpillar’s newest compact excavator models shift up to more closely reflect the actual operating weights of the machines. This results in two D-Series model designations now in the 5.0- to 6.0-metric-ton range, the 305D CR and 305.5D CR, which leverage heavier counterweights for increased lift capacity compared to the predecessor yet still marketed 304C CR and 305C CR models. The compact-radius design of the 305D CR and 305.5D CR limits upper-body tail swing over the tracks to 5.5 inches at most. Also new are the smaller zero-tail-swing 303.5D CR and 304D CR models, progressions of the predecessor 303C CR and 303.5C CR respectively. The standard two-mode auxiliary hydraulic system on the Caterpillar compact excavators allows for switching between single- and bi-directional operation, for use of attachments from breakers to augers.

VOLVO

EC55C

• 47.1 net horsepower

• 5.5 metric tons operating weight

• 12’4” maximum dig depth

• 9,302 pounds bucket digging force

ECR58

• 51 net horsepower

• 5.9 metric tons operating weight

• 11’8” maximum dig depth

• 8,768 pounds bucket digging force

With the conventional EC55C and short-swing-radius ECR58, Volvo offers models in the 5.0- to 6.0-metric-ton range from each of its compact excavator product families. Each member of the new generation of Volvo compact excavators has a side-mounted engine, providing easy access for maintenance and, says the company, less noise and vibration compared to excavators with rear-mounted engines. The Total Power Control hydraulic system provides independence of all movements and a high work rate. New Volvo compact excavator models have a float blade as standard; an angle blade is offered as an option on several. As with its smaller ECR brothers, the ECR58 has a counterweight that turns in the width of the tracks.

MUSTANG

6003

• 57 net horsepower

• 5.705 metric tons operating weight

• 12’7” maximum dig depth

• 8,296 pounds bucket digging force

Sister brand to Gehl, Mustang offers a corresponding range of excavators in the compact and slightly larger range, including the conventional 6003 in the 5.0- to 6.0-metric-ton class. This model has a side-mounted engine for reduced noise, heat and vibration to the operator’s compartment. The same units, from the 3803ZT to the 8003, also feature a side-tilt cab providing access to the components on the frame which, says Mustang, is built as a true “X” frame for better stability from the undercarriage to the house structure. Additionally, cushioned cylinders for the boom, dipper stick and boom swing provide smooth operation and longer life to the working joints. A heavy-duty bracket already mounted on the dipper stick saves buyers on set-up required to add a thumb for handling applications.

IHI

55VX-3 (new)

• 37.1 net horsepower

• 5.7 metric tons operating weight

• 12’5” maximum dig depth

• 10,850 pounds bucket digging force

55N-3 (new)

• 55.5 net horsepower

• 5.8 metric tons operating weight

• 12’8” maximum dig depth

• 11,071 pounds bucket digging force

With nine zero-tail-swing and three conventional style models, the newly-updated range of IHI compact (and slightly beyond) excavators marketed in North America includes one model of each configuration in the 5.0- to 6.0-metric-ton class. The zero-tail-swing 55VX-3 and conventional 55N-3 feature IHI’s redesigned operator’s stations, in which more room was created by moving the auxiliary pedal and two-speed travel control to the joystick. IHI excavators are equipped with one-piece booms, reinforced backfill blades, steel counterweights and oversized travel motors. The machines, regardless of configuration, come with variable-displacement piston pumps, standard auxiliary hydraulics and a choice of steel or rubber tracks.

TAKEUCHI

TB153FR

• 38.2 net horsepower

• 5.65 metric tons operating weight

• 12’10” maximum dig depth

• 11,093 pounds bucket digging force

The design of Takeuchi’s FR – or Full Rotation – Series excavators is “more than just” reduced- or zero-tail-swing that limits the overhang of counterweight at the rear, says the company, but rather “an entire package” that uses a side-by-side boom configuration to reduce front swing and tighten turning radius. The FR boom allows the excavator’s operator to dig off-set along each track or even a square hole, and yet retain vision of the attachment throughout the working range. Below 6.0 metric tons, Takeuchi offers two FR models including the 5.65-metric-ton TB153FR, and seven excavator models in total. Recently, select Takeuchi compact excavators have been updated with auto idle, a dozer blade and, for the auxiliary hydraulics, features such as detent, progressive slide switch control and an available second circuit.

KOMATSU

PC55MR-3

• 38.2 net horsepower

• 5.2 metric tons operating weight

• 12’6” maximum dig depth

• 8,770 pounds bucket digging force

Newly updated, Komatsu’s compact excavators boast faster hydraulics, low-effort proportional pressure control levers, reinforced arms with integral hydraulic thumb buckets, and monitor panels with simplified, easier-to-read gauges. Further increasing production, says Komatsu, is a new dozer blade control incorporating the two-speed drive switch with the lever. Komatsu models PC27MR-3 and up, including the 5.2-metric-ton PC55MR-3, have a high-strength “X” frame design offering improved ground clearance. The cab tilts forward for access to the hydraulic valve, swing motor, starter and alternator. In what the company describes as an industry-first for compact equipment, Komatsu provides its wireless fleet management system, Komtrax, as standard on models PC18MR-R and up.

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