Compact Excavators for Small- to Mid-Sized Jobs

Improvements in power, safety, and comfort in compact excavators

Credit: Bobcat

Editor’s note: This article first appeared in the June 2016 of GX Contractor.

If you’re a contractor working on mid-size to smaller projects, there’s good news to be found in the growth of the compact excavator market. All the major manufacturers continue to provide the industry with a wide variety of choices in both size and attachment options—especially in the 2–5 ton range, where we’re seeing the introduction of a number of new models. In fact, there might even be too many choices available, but let’s take a look at some of the new models and their features.

We’ll start our tour with some offerings from CASE Construction Equipment, Racine, WI. The company’s “mid-sized” product line includes five models in the CASE B Series and two C Series excavators. CASE notes that the B Series compact excavators were designed for increased productivity and performance, with independent, center-swing booms that allow operators to dig around stationary objects and alongside obstacles.

A foot-controlled boom swing allows for simultaneous operation of the boom. Coupled with a center-swing design that angles the boom up to 80° left and 65° right, operators can dig and use attachments around trees and parallel with foundations. This feature gives operators a higher level of efficiency, according to Katie Pullen, brand marketing manager with CASE Construction Equipment. “One of the important things about running a compact excavator is the ability to multifunction as much as possible,” says Pullen. “Sometimes you have the swing integrated into the handles and you can’t multifunction because you have a lot of things going on with the handles of the hydraulics, and your controls. “With ours, it’s foot actuated which is more of a traditional operating method for the operator. Especially if you’re operating on the edge of a house or having to dig a septic tank or dig a straight trench. It’s nice to have that independent boom swing because you don’t have to reposition the machine.”

Credit: Terex The Terex TC352R

Credit: Terex
The Terex TC352R

The CASE lineup features large excavator benefits, including an undercarriage with heavy-duty travel motors, and heavy plate guards that prevent damage to the hydraulic motor piping. The B Series compact excavators have a hydraulically controlled backfill blade for stability and light dozing work, and a swing-out access panel for quick access and serviceability. For extremely tight working conditions, the CX17B features retractable tracks that go from 52 inches wide down to 38 inches wide, helping operators get through tight gates, doorways, and other confined spaces.

The CX55B minimum tail swing model (recently certified Tier 4 Final) provides good lift capacity, digging force, and operator comfort. With a 37.4-horsepower engine and an operating weight of 11,312 pounds, the CX55B offers enough size and power to tackle a variety of construction applications. The machine’s large boom and arm offer a good reach, plus 11,128 foot-pounds of bucket digging force and a digging depth of 12 feet and 10 inches. Moreover, its compact size and cab height of 8 feet and 4 inches makes it easy to transport between job sites.

CASE models also feature a two-speed travel drive function that matches speed and performance to job site conditions. “The automatic two-speed automatically upshifts for you,” says Pullen. “If you’re using the dozer blade and you need more pressure and torque, it will maintain a higher torque speed. But if you’re doing a travel speed all your priorities go to your tracks. The hydraulic system is always going to give priority where you need it.” For fuel efficiency, all models also include one-touch engine deceleration to quickly cut engine RPMs for greater fuel savings and reduced noise levels.

A fuel-saving 37.7-kW Cat C2.4 turbo engine helps the new Cat 307E2 expand the mini hydraulic excavator machine range for Caterpillar, Peoria, IL, Cat also added a high definition hydraulic system, for load sensing and flow sharing. The 307E2 offers stability, reach, and lift capacity with its standard tail swing and fixed boom design. Inside the cab, a COMPASS monitor allows the operator to quickly enable and modify machine features such as an adjustable auxiliary flow for enhanced work tool control, hydraulic quick coupler selection to change work tool attachments at the touch of a button, auto engine idle for improved fuel efficiency, and security system features to protect equipment on the job site.

Secondary auxiliary lines come standard on the 307E2 along with a “thumb ready” stick. A Power On Demand feature ensures full-time efficiency and power; site reference system aids with grading and level trenching; and the rear view camera decreases blind spots and aids in machine positioning.

Blind spots around the cab are a nuisance, but what about the depth of the hole or trench you’re digging? Typically, there’s a worker standing around waiting to put a depth gauge down to check things—or worse, the operator gets out of the cab and checks it. Either way, it’s a waste of time, according to Tom Connor, an excavator product specialist with Bobcat Co., a compact equipment division of Doosan Infracore Construction Equipment America, Morrow, GA. “A third of my phone calls from contractors are about our depth guidance system,” says Connor. “Contractors want to save time and costs and customers want to avoid over-digging and under-digging. You have to clarify that this is a guidance system and we’ve had these kind of systems on loader attachments that are just a little different. First, you have to establish the start point when you begin digging. If I was an electrician burying cable more often than not I would have a minimum cover requirement, I could touch the tooth to the surface before I start digging, and push a button called a bench button, which is basically telling the system from this point where my tooth is at right now, compared to the desired depth that I choose. In our control panel the owner can preset a range of targets that he might work with commonly.”

The depth guidance system is available on Bobcat’s 3- to 5.5-ton machines. In the 3- to 4-ton size class Bobcat’s E32 compact excavator features a 33.5-horsepower (hp) Tier 4-compliant, non-DPF engine, plus enhanced operator comfort and a dig depth of 10.2 feet. A forward-mount instrumentation system allows the operator to maintain awareness of machine vitals, and improves ergonomics when the operator is interacting with the panel. For those contractors needing a heavier machine, the 10,677-pound E50 compact excavator features a 49.8-hp Tier 4-compliant, non-DPF engine, and has a 12% increase in torque from its previous iteration.

More torque and other useful features are prime motivators for large contractors that are adding compact machines to their fleet. “These contractors with larger equipment are seeing that in many cases the right sized machine makes sense for the task at hand and can make all the difference it in terms of efficiency, without destroying sensitive environments,” says Connor. “And it’s much more convenient to avoid dragging out a 25,000-pound machine and all the hassle that goes along with the big trailer, when you can send one guy in a smaller truck and trailer. Even though in some of those cases you could do the job a little quicker with the full-sized machine, it doesn’t pay by the time you get done transporting it around. And of course, the fuel economy is important and is proportional to the size of the machine.”

At John Deere, Moline, IL, the company continues to upgrade its G-Series excavator lineup with the introduction of the 17G and 26G compact excavators. The 17G and 26G incorporate a 14.5-hp and 20.0-hp Final Tier 4/EU Stage IV diesel engine without the complexity of an aftertreatment system. Because even these smaller machines are seeing longer hours on the job site, the operator station has a new suspension seat with adjustable wrist rests. Foldable travel pedals are positioned to provide efficient operation with maximized foot room. A third service door to both excavators provides improved access to the cooling core and other daily checkpoints. A manual wedge-style quick-coupler speeds switchover, going from buckets to other attachments in minutes. Previous D-Series attachments will work on both the 17G and 26G too.

At Volvo Construction Equipment, Shippensburg, PA, the company has seen great strides in fuel economy. Volvo recently introduced the RV20D, a compact excavator featuring an engine update and a new automatic idling system. The new EC20D is powered by a Volvo D0.9A Tier 4 Final engine, pushing 16.3 horsepower and boosting fuel efficiency by 10%. The machine is also equipped the optional auto engine shutdown feature. A new auto idling system switches engine speed to idle if the machine’s controls are inactive for more than five seconds.

Volvo’s range of compact excavator products includes eight models, with the most powerful being the EC60E. with a maximum gross power rating of 59 hp. All told, it’s a versatile range for a versatile machine, according to John Comrie, utility product manager at Volvo. “Basically the weight and the dimensions make them great machines, and the 7,000- to 8,000-pound machines still fit on a trailer comfortably, so you can still have room for extra buckets and the extra weight on the trailer,” says Comrie. “These are ideal machines for prime contractors because they can do light work and heavy work, and landscaping or trenching and digging. And these machines have improved so much over the last years in terms of operator comfort, with air conditioning and radios and a comfortable cab. Plus with additional hydraulics for your thumb attachments and augers, an operator can load his trailer with a hammer, an auger, plus a couple of buckets, and he’s a one-man show.”

If the one-man show doesn’t have much experience, don’t worry. The Volvos also feature intelligent hydraulics that allow the excavator to automatically find the sweet spot between engine speed and hydraulic efficiency. “We added an eco-mode and that reduces the fuel consumption up to 10%.” adds Comrie. “So the operator can actually set the correct mode for his application, and instead of sitting there wasting fuel with the machine going too fast to do fine work, the operator can set the exact mode for either lifting, grading, or digging. The machine can run at the lowest rpm that’s appropriate to get the job done. By having a load sensing system and proportional pilot controls, the operator can move the levers if he wants, but it won’t change those settings. So if you’re loading a truck, the speed from the flow in the pressure will give you the best results for that application.”

If digging fast in tight places is your main application, take a look at the new products from Kobelco Construction Machinery USA, Katy, TX. The company recently announced the launch of their new SK25 compact excavator model as well as their enhanced SK17 model, with top-class digging depths of 9 feet and 2 inches and 7 feet and 3 inches, as well as powerful swing speeds of 10 rpm and 9.5 rpm to deliver shorter cycle times. The upgraded SK17 model is the smallest of Kobelco’s excavators. Weighing in at 3,836 pounds, the mini is popular on job sites where equipment needs to squeeze through gates and very tight spaces. How tight? The SK17 features self-cleaning, hydraulic side frames, which retract to a narrow 37 inches.

No discussion of compact excavators would be complete without acknowledging their popularity in the construction industry rental marketplace. In fact it’s an area of fierce competition among manufacturers, as exemplified by the recent announcement from Terex Corp., Westport, CT, regarding “four ‘rental-ready’ models: Terex TC16-2, TC22-2, TC35-2, and TC35R-2 compact excavators.” So, what features define a rental-ready compact excavator? Terex notes that their machines have new exterior designs, operator-focused workstations, modern excavator controls, and digging performance features for productive operation.

Credit: Bobcat Bobcat’s depth guidance system

Credit: Bobcat
Bobcat’s depth guidance system

For digging performance, the new Terex excavators are equipped with hydraulics load-independent flow distribution (LUDV). In essence, the LUDV transfers power to the attachment in use, so even while working under hard soil conditions, the bucket offers strong ground penetration, yet the machine remains stable even on rough terrain. For rental customers that might not have a lot of experience, these machines offer precise control of attachment tools such as hammers or cutters, and the second auxiliary circuit is operated with an electrically proportional control. This means the operator will enjoy precise joystick control.

Because operators are spending longer hours in these machines, these compact excavators have cabins with a second door on the right for additional entry/exit, something that comes in handy for road construction, direct communication, and visibility. The console can be raised for more space to enter the cab, and large foot pedals accommodate those big work boots. In another nod to the rental industry, an automatic swing brake locks the upper carriage for transport. Terex notes that particular focus was placed on enhanced ergonomics, to keep operators productive. For example, all models are equipped with pilot-operated controls that provide both easy operation and changeable control patterns to best suit the operator’s preference. And, the blade lever offers an integrated travel speed controller to make it easy to level and dig. Finally, for the staff back at the rental agency that service these machines, there’s easy access and combined service points. The engine hood opens wide, and daily inspections are directly accessible, along with fluid level monitoring through gauge glasses. The filling port is conveniently accessible for direct fueling from canisters without a hose.

Making routine maintenance easier is a trend with construction equipment manufacturers. For example, new compact excavators from JCB, Savannah, GA, feature a 100% bushed design, leading to extended 500-hour greasing intervals. JCB recently announced an additional three compact excavator models, with operating weights from 10,000–12,500 pounds. These units are available in conventional and zero tailswing configurations.

“It’s all about being able to do the job as quickly and efficiently as possible and limiting the downtime and machines where you have to service them.,” says Jordan Dey, compact excavator product specialist at JCB. “One of the biggest features for these machines is that the front bushings can go 500 hours and require much less maintenance.” All three models share a design proven on the company’s larger machines, with 100% steel bodywork and four-plate dipper arm construction.

“Typically, these machines and going to rough terrain and JCB engineers are looking at ways to minimize the time spent maintaining these machines for the job they have to perform,” says Dey. “So we moved away from plastics and have 100% steel body works in order to retain residual values. And if anything does happen steel can be repaired rather than having to replace the whole part because it’s broken plastic.”

For digging versatility, JCB has also redesigned the pin pick-up points to be compatible with a variety of bucket brands, while optional hydraulic or manual quick hitches can be specified for faster attachment changes. JCB has developed a new range of Eco buckets, with a redesigned profile for easier filling and improved material retention. “We have a hydraulic quick hitch so operators don’t have to get out of the cab,” adds Dey. “The hydraulic quick hitch gives you the ability to detach from one attachment and pick up another one, and that includes different competitor’s attachments, but also attachments that were originally designed for JCB machines. So we’re making it a universal machine.”

The excavators feature an improved operator’s cab, with the 57C-1 using the same structure as the larger 22,000-pound machine. The cab is 18% more spacious and offers up to 11% more visibility. A new display screen and control system, with an automotive style rotary dial, allow easy access to systems and information. The operator can set auxiliary hydraulic flows for two separate attachments from the cab, while the menu mode button switches the rotary dial between throttle modes, including a one-touch idle function and menu mode.

“We’ve looked at operator comfort and control because it’s really like their office for the day,” says Dey. “With more amenities it’s a more comfortable environment and we reduced noise and vibration levels. These machines come under a lot of stress and strain. To make the cabin more operator friendly, and a more comfortable environment, we put in a new display screen and different control system with a selection dial to help you scroll through the functions and make your selections as to how you’re operating the machine, so you can set your hydraulic flows and you have the option of the auto idle.”

The cab is also offered with a new soft button switch panel, to control auxiliary flow settings, working lights, beacon, wipers, and JCB’s 2Go additional hydraulic activation safety system. The new cab also features a removable floor section, requiring no tools, to access major hydraulic components. The machines feature an open undercarriage design with angled frames for easy cleaning and to prevent material build-up. All models are available with JCB’s LiveLink telematic monitoring and location service, providing customers with machine work hour data, fuel level and consumption information, and a host of critical system alerts.

There are nine power modes available, including Eco, and for the first time an H+ heavy digging mode. The machines can also be ordered ready for tilt-rotator installation from the factory, with a programmable third auxiliary function. “We’ve heard a lot of feedback about our four-way blade on our machines,” Jordan notes. “It moves up and down and side to side, and it’s something that the industry is requiring.”

All told, the industry is requiring a wide variety of options in both power and features, and manufacturers are responding. Whether it’s something as small as a machine with a 37-inch track width and a diesel sipping 14-hp engine, to something as large as a 4-ton, 57-hp beast of burden, these are still compact excavators, with all the features and economic benefits that make these machines so attractive. For first time buyers looking to take the plunge, to large contractors looking to add to their fleet, the selection has never been better. GX_bug_web

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