Excavators Moving on the Upgrade
Is it an exaggeration to say that there’s no machine in the building and construction trade more versatile than an excavator?
When it comes to moving and digging earth, these workhorses do more than pull their weight. And with so many attachments available, it’s hard to imagine a task the excavator can’t handle. So many attachments, so many models, and so many manufacturers. We can’t cover them all in one story, but here’s a cross section of new product innovations that are helping contractors improve their productivity and efficiency.
There’s nothing like a trade show for taking the pulse of an industry, and at the last ConExpo in Las Vegas, fuel economy and Tier 4 emissions standards made for a dominant theme, but according to Mark Wall, product marketing manager for excavators, John Deere, Moline, IL, look further and you see that contractors are running their excavators from sunrise to sunset, so it’s not surprising that fuel consumption would be a concern. “Our customers told us that excavators are very important to their business, and nine times out of ten it’s the first machine on the job and the last off. Because of their flexibility, excavators are great for digging and a huge source of hydraulic power for attachments.”
Looking at some of the larger models, Deere’s new Interim Tier 4–certified (IT4) G-Series line has three new entries. The 470G LC weighs 47 metric tons, with 367 horsepower to handle large commercial excavating projects and road building. The 67-metric-ton, 463-horsepower 670G LC and the 87-metric-ton, 532-horsepower 870G LC target applications such as mass excavating and truck loading.
“In response to our customers, we’ve delivered more hydraulic flow for faster work cycles and greater productivity, and a comfortable and spacious cab,” Wall says. Other features include an enhanced LCD monitor for easy access to machine information and functionality, such as engine rpm and oil temperature, maintenance intervals, cab temperature, and work modes.
Three work/power modes include high-productivity, more power and faster hydraulic response to move more material, a balance of power and speed for normal excavation, top-speed economy to help save fuel during light digging work. A “power boost” button on the right-hand control provides extra muscle to drive the bucket through tough digging conditions.
Longtime workhorses of the earthmoving industry, excavators do far more than merely pulling their own weight.
“In general, and North America particularly, contractors are on a per-day job basis, and what they told us is that they want to do things like put more pipe in the ground per day because chances are there’s a bonus for getting done early,” says Wall. “If they can beat the weather or finish a job in half a day, it’s more money in their pocket. And sometimes they’re paying rent on some other piece of equipment at the job site, and they can turn it in quicker to reduce their costs.”
The JDLink Monitoring System is another way to reduce costs. All three G-series are equipped with the telematics machine monitoring system. It features 24/7 online access to track machine health, utilization and fuel consumption. JDLink’s geofence and curfew alerts offer protection from unauthorized movement or theft.
The Fine Print Looks More Attractive
Beefed-up service and warranty packages are another trend for the industry, notes Doug Morris, product manager, Komatsu America Corp., Rolling Meadows, IL., Komatsu includes Komatsu CARE, a complete service and advanced product support solution provided by Komatsu and its distributors. “It’s an industry exclusive,” says Morris. “For our new Tier 4 products, we include complementary factory-scheduled maintenance for the first three years or 2,000 hours, and a Komatsu diesel particulate filter exchange is also included.” Further protection is available from the company’s Machine Total Care Program, an extended warranty program that combines machine warranty and maintenance for up to five years or 10,000 hours. “The whole point here is to focus on the customer and provide increased uptime, efficiency, and genuine factory service to protect the value of the investment.”
The larger excavators in Komatsu’s line certainly represent a serious investment. For example, take the PC490LC-10. At 108,000 pounds, it looks ready to consume most any load unfortunate enough to get in its way. The 359-horsepower diesel engine has the horsepower to do the work. And the work should take less time, thanks to a hydraulic-pump displacement that’s about 10% greater than the earlier PC450 model. Then there’s the upsized excavator, rated at 10% larger over-the-side lifting capacity, yet the PC manages a 5% reduction in fuel consumption. Efficiency gains come from variable-speed matching controls. The system automatically adjusts engine speed to match the hydraulic pump output for both light- and heavy-duty applications.
“Contractors are trying to do more with what they have and taking equipment to their limits, and that has really been the focus in this size class,” says Morris. “You’re seeing the class grow, and that goes along with all excavators, especially in the 50-ton range.” One example is bucket capacity for tasks such as truck loading. The 490 has a larger bucket, and more lift capacity. “When you get into utility work and have to move heavy pipe, that’s the real target, to give them more lift capacity and stability, and comfort for the operator and more capabilities out of the machine,” Morris adds.
Those capabilities include five working modes—Power, Economy, Heavy Lift, Breaker, and Attachment—to match machine performance to the application. “We put a lot of emphasis on giving operators tools to control the machine in different work modes for different applications,” Morris says. “For example, if they need heavy-duty digging, they can use our power mode. If it’s a light-duty application, they can use economy mode to save fuel. You also have the ability to go in and set up different attachments and flow rates depending on the attachment.”
The control panel also displays operation guidance, operation records, fuel consumption history, and usage data. Additionally, the monitor is used for troubleshooting and answering an abnormality or fault code. Technicians can use wireless communication to access the monitor panel, so dealers have the ability to troubleshoot before coming out to the job site. “They know when a code has been tripped and the source, so it allows them to begin analyzing the problem before they even get out of the job site. Even our small excavators have those features, because we’re trying to get machines back up as soon as possible.”
Unique Applications and Trends
Small excavators continue to grow in popularity and application, according to David Steger, product and training manager, Takeuchi-US, Pendergrass, GA.” I go into the field and see a lot of different and unique applications,” says Steger. “Anything from digging and setting pools to trenching pipelines, and I’ve even seen them lifted down into ships and barges for cleaning up bulk material out of hulls.” At ConExpo 2011, Takeuchi introduced the TB285, a mid-size hydraulic excavator that replaces the TB175. It has been completely redesigned for higher performance, increased operator comfort, and simplified service.
The story starts with horsepower, and this model harnesses a net output of 66.5, from an Interim Tier 4 turbocharged Yanmar engine. Operating weight is about 20,000 pounds with a dig depth of 15 feet. Dual heavy-duty boom cylinders handle the lifting with plenty of clearance for buckets and attachments. Options include a 21.7-inch-wide steel track, hydraulic thumb, and heavy-duty adjustable bucket coupler. Another feature that’s gaining in popularity among many manufacturers is some sort of automatic engine speed reduction system. In Takeuchi’s case it’s the TB 285 ECO Mode—a control that can be set to automatically reduce engine rpm to reduce overall fuel consumption.
Manufacturers are paying extra attention to cab designs and Takeuchi is no exception. One of the most noticeable features in their cabs is the Machine Command Center, a large LCD gauge panel with multifunction operator information, and control of the auxiliary flow from the operator’s seat. “You don't always have two attachments at the same time but with the 285 you can set one side up that may require a lower pressure and flow,” says Steger. “The operator can dial that in, and then the other attachments might have higher flow ranges, so you can have a low flow and a high flow. For our example in some areas of the country hydraulic thumbs or clamps are very common on machines and they leave those plugged in and the primary line could be used for a compactor, an augur, or you name it.”
No matter the attachment or combination, these machines typically see the most stress from heavy excavating. Stager notes that Takeuchi’s engineers designed in extra-steel, high-quality welds, and larger linchpins for all the joints, cylinders, and booms. However, he still recommends daily inspections and regular greasing intervals. “In my opinion it’s cheap insurance to keep the grease flowing, and it’s going to help push dirt out of the joints and extend the life of that working attachment or working area.”
Micros, Minis, Maxies
New models of small excavators are part of an ongoing expansion strategy at Caterpillar Inc., Peoria, IL. “I’ve been in the business about 13 years, and this is by far one of the biggest launches we have had at Caterpillar,” says Kent R. Pellegrini, global product application specialist. Pellegrini enjoys talking about Cat’s larger models, but let’s take a quick look at the new minis, or in one case, the new micro. The 300.9D is Cat’s entry into the “micro market,” and weighs just 2,061 pounds. With an overall width of just 28.7 inches, it can drive through a standard residential doorway. Caterpillar’s work-tool division will be introducing a new H25 compact breaker specifically to work with the 300.9D.
From micro to mini, the next step is the new 301.4C. It weighs 2,921–3,340 pounds and extends the company’s line of 1.5-ton products. A 24-horsepower engine powers standard equipment that includes extendable undercarriage, single and two-way auxiliary hydraulic lines, a dozer blade, and a hydraulic oil cooler. Finally, there’s the 302.7D CR. At 5,681 pounds, it’s the lightest Cat compact radius model, and easy to transport for a rental company or contractor. Two-way auxiliary lines are standard, equipped with quick-disconnects for rapid work-tool changeover. A joystick-mounted proportional auxiliary control allows for fine control of powered attachments.
Now it’s on to the big yellow iron and an excavator that represents some impressive engineering innovations, the new Cat 336E hydraulic excavator, a replacement of the 336D. Features include a more powerful engine (SAE net power rating of 300 horsepower) that meets Tier 4 Interim emissions standards, yet it delivers 12% more power and 4% faster cycle times than the 336D—plus a 2% boost in fuel efficiency.
“We’ve seen fuel costs rise astronomically, and some customers are very fuel conscious, so our machines have a high-power mode, or a standard-power mode that burns less fuel,” says Pellegrini. Additional fuel savings come from an innovative electric regeneration valve that captures and recycles energy when the boom is lowered. Controls relating to engine efficiency include a new engine shutdown setting for specifying how long the engine should idle before shutting down, plus a button to reduce engine speed to idle. Finally, there’s an isochronous speed control, which maintains a constant engine speed regardless of load, and an economy power mode to manage and conserve fuel.
“These are hybrid hydraulics,” Pellegrini explains. “They don’t have batteries, but they are electrified. On the D-series, we improved it by increasing the heavy-lift mode. If the operator uses the heavy-lift button, all power goes to the boom cylinders only and that increases the pressure. And there’s no limit on sustaining it, so once you push that button it’s on until you turn it off. That makes it a critical feature for pipeline layers because they’re getting in applications where they’re picking up some heavy pipe.”
Cat’s engineers also focused on the business end of the excavation process and introduced their Next Generation buckets, which feature enhanced geometry. The result is more efficient filling for faster digging and reduced cycle times.
Letting the Bucket Do the Dirty Work
Case Construction Equipment, Racine, WI, has also done some advanced work on its bucket design, and that’s just the beginning of the introduction of three new models in its “C” series of excavators. But let’s start at the bucket and move backwards. “All the buckets that we offer have our proprietary SmartFit system,” says Tim O’Brien, marketing manager, Case Construction. “That means that an operator with a small socket wrench and a few turns can take a tip off and replace it very quickly on all the teeth on the bucket. So you don’t need a hammer, and you don’t have to knock out pins like before. It saves a lot of time and removes the logistics of having someone come out and do it plus the downtime and level of complexity.” The teeth are self-sharpening and maintain their strength as they wear. The new designs include general purpose, heavy-duty, ditching, rock, and Couplex applications.
Those buckets will get thorough workouts from the new CX250, CX300C and CX350C. The C series replaces Cases’ B series and offers Tier 4 Interim–certified engines that deliver 177, 207, and 266 net horsepower respectively. “The C series is all about higher productivity, and we’ve updated the designs the booms and arms to be able to achieve that. We are able to make them stronger, and it allows us to make the machines more efficient at the same time,” says O’Brien.
Customers may not see the boom’s design improvements from the outside, but what’s inside makes a big difference, according to George Whitaker, Case product marketing manager. “We redistributed the weight on the boom and arm to the areas where the most momentum of inertia occurs,” Whitaker explains. “So you have better balance and durability. And we introduced a welding technique that’s widely used in shipbuilding, so we are getting deeper penetration and better durability and a longer life for the welds.”
Case has introduced some interesting technology to keep the boom moving fast, and help operators take advantage of the high efficiency engineering. The Intelligent Hydraulic System reduces total fuel consumption and the Boom Economy Control lowers engine rpms during boom down and swing operations. The Auto Economy control lowers rpms when the joysticks are inactive. “Our hydraulics have been upgraded with more sophisticated algorithms,” O’Brien notes. “Now specific pressures and flows are interpreted when the operator runs a machine, so it allows a novice operator to be comfortable and fluid. Some people call it controllability but intelligent hydraulics have come a long way in taking average operators and making them very good.”
Going With the Flow
Smart electronics are boosting productivity and fuel economy up to 11% for excavators from JCB, Savanna, GA, according to Ryan Connelly, product marketing specialist. “One of the things we’ve done is allow for simple improvements such as letting gravity assist boom-down functions,” says Connelly. “Basically we’re just optimizing the hydraulic systems so they don’t restrict the flow back to the tank and that allows faster cycle times and more assistance from gravity to drop the boom down.”
JCB’s Advanced Management System (AMS) controls vital functions and also records all key operating data and for detailed diagnostic information. The four work modes include auto mode, which automatically provides maximum power as needed; the economy mode, which provides maximum fuel efficiency in normal conditions; the precision mode, giving more control and accuracy for fine work and grading; and the lifting mode, which offers maximum power with controllability. “Auto mode is 100% power and 100% hydraulic flow and automatic pressure boost when required,” says Connelly. “But in a lot of applications and conditions you don’t need to work at that high level, so we have revised the computer so that if the excavator should be off for more than 90 minutes it will start in economy mode, and that will definitely reduce fuel consumption. Basically, you have a combination of improvements to the hydraulic system and starting up in economy mode and things like that will have an effect on the overall fuel savings.”
Connelly describes JCB’s JS220 model as the backbone of the market because it’s a machine that can work most applications from municipal projects to building construction, plus road work and even in small quarry applications. The 220 weighs in at 49,450 pounds, and is driven by a 172-horsepower engine. “You see all sorts of applications, but with the increase in waste and recycling it can be very rough on these machines,” he notes. “As a result, we’ve come up with a package called the XP machine and you’ll see a lot of reinforced steel for the guards and wear strips on the dippers so if they're banging against concrete or bins and such you have the strength to withstand that. You see material falling on the machine so we have a hydraulic raise option so the operator can see better.”
North American customers also have the option of parts ordering from three locations with the opening of JCB’s new West Coast parts facility in Fontana, CA. “The West Coast allows us to get parts to customers quicker on that side of the US and we have other parts warehouses in Savanna and Burlington, ON, so things are very positive for the future of this market
Investing in America’s Future
Excavation equipment for the North American construction industry has an important place in Volvo Construction Equipment’s future. In early 2011 the company announced a $100 million expansion of its US production facilities, and announced many new products at ConExpo 2011, including new-generation D series excavators. As with other manufacturers, the new Tier 4–emissions standards have driven much of the new designs, according to Henrik Loserius, global product manager of excavators at Volvo. “This is something that we are focused very much on,” says Loserius. “We can see fuel prices increasing and the cost of ownership will be dependent on operating costs. So that ties in with our environmental focus along with the concern for lower cost for the customer.”
For an example of fuel efficiency, Volvo’s new EC250D and EC300D excavators offer improvements in consumption over previous models by 9% to 13%. That’s an impressive achievement considering that these are heavy-duty machines weighing 54,230 to 61,730 pounds respectively. Both machines use Tier 4 certified Volvo D8H engines, which feature a waste-gate turbo, externally cooled exhaust gas re-circulation. Maximum power ratings are 202 horsepower for the EC250D and 227 horsepower for the EC300D. Overall it’s an increase in power with up to 13% higher fuel efficiency.
Volvo’s Contronics mode selection system offers five working modes (idle, fine, general, and heavy) that optimize fuel consumption by matching performance to application. Further gains are possible with an attachment management system that stores up to 18 different attachment presets for hydraulic flow and pressure adjustments.
“You have to increase productivity and at the same time make the machine more efficient,” Loserius explains. “So looking at the total cost of ownership you have items such as longer service intervals, longer lifetime of components, and more. I meet with our customers, and they say it’s difficult to get competent operators, so we have developed a training system.” Volvo’s Eco Operator provides practical and theoretical knowledge for safer equipment operations. Subjects include correct machine operation and maneuvering, as well as how to plan work in the smartest, most efficient way.
More Strength With Less Steel
Efficiency combined with versatility is one of the key reasons excavators continue to grow in popularity, notes Keith Rohrbacker, product manager, Kubota Tractor Corp., Torrance, CA, “I’ve been doing excavators quite a while,” says Rohrbacker, “but they really started to take off in the late ’90s because customers thought that the cost of maintenance on their tractors was too high, and they were looking for a way to reduce their costs.” Since the ’90s, Kubota’s engineers have taken advantage of cost reductions from using computer-aided drawing and stress analysis to design stronger products without adding a lot of steel and weight.
Strength is important because as customers get familiar with their machines they tend to push them to the limit. “They will lift the heaviest objects possible to see how far it can go,” says Rohrbacker. “So it’s amazing what they can do with the power and stability built into these machines.” With 12 models available, even the pushiest of operators should find the right size and power options to handle their needs. For example, look at the newest additions to the compact excavator lineup, the Kub KX057-4 and Kubota U55.
The KX057-4, is a 5-ton conventional tail swing compact excavator with an optional hydraulic float angle blade (25-degree pivot angle), plus auto-downshift travel motors for increased productivity. The U55 5-ton tight tail swing (2.5 inches of tail swing overhang) is the largest model in the U-Series of compact excavators. Both units use Kubota’s 47.6-horsepower direct-injection diesel engine to keep the dirt moving. An advanced load-sensing system provides optimum oil flow and enhanced fuel economy. Auto-downshift travel motors smooth transitions through turns, and the optional hydraulic angle blade improves backfilling efficiency. The cab has a new digital display panel, wide doors and a large operator space. An auto idle feature conserves fuel and reduces noise level.
To maximize productivity, and attachment versatility, auxiliary hydraulics ports allow the operator to exchange hydraulic attachments and leave the thumb connected at all times, speeding attachment changes. The auxiliary hydraulics system is equipped with attachment flow presets from the control panel and thumb-ready sticks to speed attachment installation and changes.
Tracking Maintenance Online
At the Gehl Co., West Bend, WI, customers have access to a full line of compact excavator models with operating weights ranging from 3,560 to 25,397 pounds. Zero tail swing and short tail swing plus some of the largest operator cabs in the industry have been popular features. Gehl’s Model 153 headlines the company’s offerings with an operating weight of 3,759 pounds, a dig depth of 7 feet, 2 inches, and net power of 23.7 horsepower at 2,200 rpm.
To get the most out of engine and hydraulic components, Gehl’s VitalTRAC fluid analysis program offers a preventative monitoring tool that can protect equipment by utilizing a user-friendly fluid analysis program that can monitor equipment performance and component life online. By using the VitalTRAC program to routinely test engine oils, coolants, hydraulic oils, gear oils and fuel, in conjunction with a regimented preventative maintenance program, customers can benefit from extended machine and component life, plus optimized fluid change intervals.
Three Products Rolled Into One
New model updates from Bobcat, West Fargo, ND, are also addressing the growing role of attachments. On the company’s new E32 and E35 M series excavators, auxiliary hydraulics, angle blade and Hydraulic X-Change mounting systems for quickly switching between 16 attachments, are standard features. “The M series is an evolution of a product category and first and foremost their designs represent the voice of our customers,” says Tom Connor, Bobcat’s excavator product specialist. “Many customers would like three different products but the budget only allows for one. So the ultimate goal is provide enough features to make the customer happy.”
Not surprisingly, customers want more power, and Bobcat has introduced an advanced hydraulic system that increases arm breakout force by 10% over previous models. Sometimes more reach can improve a customer’s productivity and an extendable arm option provides 30 inches of additional reach. Other features include Auto-Idle, which can be enabled at the operator’s discretion to automatically idle the engine if the excavator’s functions are not used for four seconds. Idle mode saves fuel and reduces noise. The machine returns to the preset throttle position when operations restart. For precision movement, the boom-swing control is now on a thumb switch on the left joystick, and a new easy-to-use rotary knob allows precise engine speed adjustments. Bobcat offers 11 excavator models.
Overall, we’ve seen that manufacturers keep releasing new models and innovative features. Fuel efficiency and productivity continue to rise, as does the choice of attachments. So it may well be safe to say that there really is no machine in the contracting trade more versatile than an excavator. And, maybe, none more valuable.
Author's Bio: Writer Ed Ritchie specializes in energy, transportation, and communication technologies.