T4-I, Hydraulic Tweaks Make Smaller Excavators More Efficient

March 30, 2012

Like many other machine categories, the market for crawler excavators weighing between 20,000 and 40,000 pounds is working to gain traction after a couple of very difficult years, but manufacturers haven’t stopped making improvements.

Buyers will see some new T4-I engines, increased fuel economy, and practical hydraulic changes designed to make machines more productive and efficient—a key for today’s market. The category is also seeing increased popularity in rental.

Rental is a “launch point” into the category for many contractors.

Like many other machine categories, the market for crawler excavators weighing between 20,000 and 40,000 pounds is working to gain traction after a couple of very difficult years, but manufacturers haven’t stopped making improvements.

Buyers will see some new T4-I engines, increased fuel economy, and practical hydraulic changes designed to make machines more productive and efficient—a key for today’s market. The category is also seeing increased popularity in rental.

Rental is a “launch point” into the category for many contractors.

“With the economy going down, rental has gone up,” says Caterpillar’s Kent Pellegrini, global application specialist for excavators. “These machines are priced to rent. Rental also allows customers to experience them and get informed for making purchases later.”

Aaron Kleingartner, segment application marketing manager for Doosan, agrees.

“We feel that as the recession continues to diminish, we’ll see an influx of machines in the rental market. Contractors might be skeptical and turn to renting a piece of equipment for one job, and then maybe roll that rental into a purchase. In this economy, these will be some of the first indicators on how the market is turning around,” Kleingartner says.

“In this type of market, everyone’s trying to get the most out of any machine,” Cat’s Pellegrini says. “You can’t blame them for being cost-conscious. The next size class up can be too expensive when jobs aren’t plentiful,” Pellegrini says.

As a result, contractors are pushing the 20,000- to 40,000-pound category to do more. Doing more with less fuel is also important.

Caterpillar is offering two new excavators in the category, the 94-horsepower 312E and the 316E at 113 horsepower. Both models are said to offer fuel savings with new T4-I engines.

“These are not necessarily the productivity updates like larger models are getting, but they get fuel consumption reductions—about 6 percent when you’re trenching in utility applications,” Pellegrini says. “This is really a customer-based change. Utility customers are more fuel conscious. They want to watch their fueling intervals. Also, in rental applications, the more fuel efficient you can be, the better—it makes the rental go a lot longer.”

Pellegrini says European sensitivity to fuel consumption in this category has been a long-standing situation. “In Europe, it’s been more critical because of the cost of fuel, but the cost of fuel is rising here,” Pellegrini says.

Indeed, the cost of fuel has already affected operating costs, which have risen an average of $6.33 an hour for the category over the last three years, according to EquipmentWatch.com. With diesel about to rise even higher this year, manufacturers are more serious than ever about fuel savings.

“You’re going to see more of these machines become more fuel efficient,” Pellegrini says. “In the past, when Caterpillar delivered more horsepower and more production, you could bet the fuel consumption was going to go up, but this is the first time in Cat history that horsepower went up and fuel consumption went down for medium and large Cat excavators. We got the high fuel burn back down with hydraulic efficiencies. Customers with bigger machines are seeing this right now.”

Hydraulic efficiencies are another common improvement in the category.

“The market for these excavators has remained pretty constant in this last year in terms of sizes,” says Jamie Wright, Terex product manager. “Hydraulic performance is one of the key factors for a compact excavator, as it affects both lift and load capacities,” he says.

“The market is trending toward features and benefits that work to either reduce cost or increase productivity. The economic conditions over the last 1½ years have forced manufacturers and customers to maximize uses for their machines,” Wright says.

Terex has equipped its entry in the category, the TC125 (27,558 pounds, 100 horsepower), with top-mounted boom cylinders to provide protection from impact with loads. “We also invert it so the seal is facing down,” Wright says. “This prevents dirt build-up and protects it from the elements.”

Along with spherical bearings, the top-mounted cylinders help protect the component in demolition and landscaping applications where the excavator has to move large, heavy material without damaging the hydraulic cylinders and incurring downtime.

Axial-piston, variable-displacement hydraulic pumps and motors provide load-sensing and load-independent flow division hydraulics for simultaneous operations. “With this design, oil flow is distributed to cylinders independent of the load,” Wright explains. “The main advantage of this system is that the excavator can be performing multiple actions at one time, without sacrificing flow.”

Takeuchi’s TB285 debuted at Conexpo and hit the market in mid-2011, replacing the company’s TB175. The TB285 is at the bottom of the range, a 20,000-pound machine, with 69 horsepower and a 15-foot dig depth.

Both it and the larger 31,000-pound, 98-horsepower TB1140—which was upgraded with a heavy-duty blade, multiple auxiliary lines and a choice of rubber or steel tracks—have a number of hydraulic improvements aimed at efficiency.

Primary and secondary hydraulic circuits have an adjustable flow system that can be adjusted from the operator’s seat via proportional thumb slide switches located on each joystick. A continuous mode aids hydraulic motor-driven attachment operation. The third auxiliary line makes it easier to install a hydraulic quick-attach.

Boom and arm holding valves reduce cylinder drift and help maintain load control in case of hose failure. A lift alarm can be activated to provide an audible alert when the boom is reaching its hydraulic lift capacity. There’s also an accumulator that allows operators to release residual pressure in the hydraulic circuit, making it easier to change attachments, as well as to allow work equipment to be lowered after stopping the engine.

In addition to hydraulic tweaks, manufacturers have worked to make this size class of excavators more attachment friendly. OEMs are keeping a close eye on action and preferences in the field.

“Buckets, thumbs, and hydraulic breakers remain the most popular attachments for Terex compact excavators,” Wright says. “We are seeing more demand for mulching heads for compact machines as their hydraulic capabilities increase.

“I think these attachments are popular because the number of applications within different industry segments for compact excavators has grown as their potential is realized,” Wright says. “For example, we’ve seen a small trend towards newer applications such as vegetation management.”

The category is also becoming more popular with landscapers and materials’ yards, thanks in part to a specific configuration.

“The biggest thing we’re seeing is thumb usage, by far,” Pellegrini says. “This is for handling very expensive rock and placing it for retaining walls. Proportional controls and auxiliary hydraulics allow you to clamp that thumb down to help place that material. A skid steer or a compact track loader will be limited on how high they can place.

“An excavator with a thumb not only has the ability to modulate the clamping force, but it also has the pressure it takes to rip—for instance, the thumb can be useful, with full rotation, for ripping out trees. Plus, they’re quiet machines, with the ability to work between homes at reduced noise levels. That’s big for fiber optics, or running a new water line into a house or neighborhood,” Pellegrini says.

Pellegrini has also seen some non-traditional work being done in the category by contractors looking to fill gaps in their income and keep machines working. “You’ll see ‘gap applications’ like indoor jobs, where contractors will want to convert the machines over to propane,” Pellegrini says. “That’s a gapped application, indoor demolition; as in a niche gap that’s not normal.”

Doosan’s Kleingartner is seeing thumb use, but also notes another trend. “Plate compactors are real popular, as they’re used to finish off a trench, or even in the bottom of footings for smaller properties,” he says. “Breakers are popular in this size class on rental units. More people are renting them together on long- and short-term rents.”

There are also contractors’ traditional needs for reduced tail swing units and machines that don’t need a permit to travel (depending on individual state regulations on width and weight).

“Contractors are looking for smaller tail swing units, especially in road work, to reduce lane closures and keep traffic moving,” Kleingartner says. “They’re also looking for the ability to transport more easily. Unlike larger machines that stay on projects longer, this size class is moved around more frequently.”

The DX140LCR is Doosan’s 32,408-pound compact radius offering in the category. In addition to a shorter tail swing, it has a ROPS-certified, pressurized cab, an upgraded monitor panel with an automatic day/night mode, and a rear-view camera as standard equipment.

Hyundai introduced a new a reduced tail swing model last year. The 113-horsepower R145LCR-9 was specifically designed for close-quarter areas. The tail swing over the side is 7 inches, allowing the unit to work very close to buildings, roadways, and other site obstacles.

The installation of T4-I engines has influenced other recent offerings in the 20,000- to 40,000-pound category. Link-Belt has released a new series of excavators with the X3 designation. The five X3 models in the 20,000-40,000-pound size class now meet T4-I requirements with Isuzu diesels that utilize a high-pressure common rail fuel injection system and exhaust-gas recirculation (EGR) technology. The company says the new generation of machines has greater fuel efficiency, faster cycle times, and increased lift capacities over its previous generation.

The X3 excavators also have new ROPS-certified cabs and 7-inch high-definition color monitors to track all machine functions and view the feed from the new rear-view camera. Both the 130X3 and 145X3 have two different undercarriage options: a long undercarriage, and a regular undercarriage with a dozer blade.

Hitachi recently upgraded its ZX160LC-5, while the ZX180LC-5 is an entirely new model for the North American market. Both models were driven by the change to T4-I engines and use the EGR platform with a diesel particulate filter to meet EPA regulations. As many manufacturers are finding, the T4-I changes give them the opportunity to add features, as well as update cab creature comforts, service access points, and available options.

This means buyers will continue to see many choices and price points, but Terex’s Wright offers an important bottom line: “When choosing an excavator, make sure the piece of equipment is going to meet your job site needs—don’t sacrifice power, breakout force or anything else just to save a dollar. Always buy quality.”