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Those who drive the tractors seem to know better than anybody what they really need for successful projects. By Paul Hull |
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What is a tractor anyway? Three answers come to mind immediately, depending on whom you ask. To many people a tractor is a machine that works on a farm; it is considered rural rather than industrial or construction equipment. To others it pulls a large truck along interstate highways; it can include sleeping accommodations. In the construction industry, those who talk about tractors usually mean dozers. There are other close relatives: all those machines that can run on tracks. They could be skid-steer loaders, pavers, loaders (tracked, not wheeled), telescopic handlers, and cranes. Some contractors seldom use tracked machines because the nature of their work does not require them, but there are many of us for whom the use of tracks can secure contracts and profits that would otherwise have been lost to better-equipped competition. Sometimes winter arrives early (as it did in several states last year), and proposed jobs might never start because wheeled machines cannot cope with the muddy or slippery ground conditions. Having tracked equipment available can prolong the work season by several weeks when those hostile ground conditions prevail. You could rent a tracked loader, for example, or you could see if a set of tracks to go over the existing wheels temporarily is a valid option. It’s simple arithmetic. How much do tracks cost? How much business will they bring in that you would otherwise have lost? "We hate to lose a productive day if we don’t have to," comments Bill Orsborn, who owns Land Technique in Delaware, OH. "I’ve been operating skid-steer loaders for more than 20 years and bought a Bobcat 864 [now renamed the T200] compact track loader. It extends our work season through the winter, when skid-steer loaders can damage the ground with ruts in muddy conditions." The tracked loader has also proved a good machine for grading. "The tracks make it much easier to cut and fill and smooth and backdrag." Slightly smaller than Orsborn’s model is the T190 track loader. There are different styles of tracks, for different purposes. Case H-Series dozers offer three track options. The long-track version has a narrow width for better maneuverability and easy transportation. The wide track can match with a wider blade for finish grading. The low-ground-pressure models explain themselves and have been successful where that feature is critical to success. Rubber tracks are available for use on easily damaged surfaces, such as concrete or asphalt, and those applications seem to increase as we have more and more bridge, road, and residential work for the dozers.
If you run dozers, you’ll appreciate the improvements that have been engineered for them in recent years. Although many contractors will openly acknowledge that much of the success and profitability of these basic construction machines can be attributed to the skilled operation of the person at the controls, they will agree that new technologies of control and accuracy have made that task easier. Simplicity of operation has become even more critical with so many reports nationwide that skilled operators are difficult to find. "We are a small company, and one of our greatest challenges is to find and keep employees who run our machines well," notes Shirley Reed of Ralph Reed Excavating and Septic Services in Brown County, IN. "We have been lucky." That company’s work is mostly within easy reach of the home base, and its size and workload are probably similar to those of thousands of contractors. How do you keep skilled employees? The hourly wage is not the only answer. For a company like Wilde Construction, based in Shevlin, MN–but working contracts (many for utility construction and installation) all over the United States–reliable operators are most valuable because much of their work is not done within a day’s drive of home base. "Once we find somebody good, we try to keep him," says Brad Mistic, a foreman for Wilde, whose crew worked in rural Montana last year. "We have our operators out for three weeks and home for one. It seems to work well." Wilde has its own planes and uses commercial airlines to serve the needs of away-from-home workers. When contractors are busy, as most have been for several years now, finding skilled employees is even more difficult. That is why another question you should ask of the tracked machines you want to use is: "How easy are they to run?" For Midlands Contracting in Kearney, NE, that is important. "We use Bobcat 753, 863, and 873 loaders for our utility work because they allow us to use unskilled operators and give them a chance to develop their machinery operating skills," explains Dallas Wegner, president of Midlands Contracting. "Our machines are operated mostly by laborers and form setters because they are so easy to run." We all have our favorite brands and manufacturers (as we do for cars and pickups), but not every manufacturer keeps up with engineering advances. Occasionally we should ask ourselves if somebody else hasn’t overtaken our favorites in technology, price, and service.
Kobelco offers the Blade Runner, which is a combination excavator and dozer. Officially called the ED180, this machine has the productivity of a 90-hp-class dozer and can dig and lift more than a 16-ton machine can. The Blade Runner has been successful in such varied jobs as grading, digging trenches, laying pipe, backfilling, heavy dozing, lifting and carrying materials, cutting slopes, doing the finishing work, and clearing sites. One of the appealing aspects of such a machine is that one operator can do both your excavation and dozing–another way to beat that "no skilled labor available" problem. For that operator, a single dozer lever controls all the hydraulic functions of the blade. The six-way blade can have a power angle tilt or a power-tilt manual angle, designed particularly for finish grading, dozing, landscaping projects, cutting "V" ditches, and backfilling. Operating a dozer has its own jargon and dozer operators, according to their coworkers, are a different breed (but most valuable). A dozer working fast is a joy to watch–proof of the value of the combination of good engineering and good driving. Listen to your operators. They can tell you what to look for in a productive, profitable dozer. Several owner-contractors assert that sometimes they think the operators talk to the dozer and ask it what it wants. With all the talk of "the new series" of dozers–H seems to be popular at the moment–don’t forget that the right operator can make an older model perform well too.
One of the latest innovations comes from Komatsu America International Company, and it’s called Komstat. "It is a superior hydrostatic system that gives the operator superb maneuverability in all conditions," explains Ed Warner, dozer product manager. "Our Komstat technology enables the dozer line to outperform standard models, with ease of cutting across slopes, the ability to work in tight conditions, and easy turning. It would be especially effective in the tight conditions found in site prep, general construction, home building, and fiber-optics installation." By noting the aspects of the dozer’s operation addressed by Komatsu in this new hydrostatic system, we can discern important features to research for any dozer. "It must turn easily" might be the most commonly expressed requirement for a dozer. "I wish we could get rid of that cross-steering on the downhill slopes" was also a popular lament. Those problems have been addressed and should become obsolete soon. They are traditional challenges that might mean nothing to younger operators. Since the clutch is not disengaged when steering on slopes with a hydrostatic steering system, cross-steering is not necessary and the engine power is continuously transmitted to both tracks. Ask your distributor or manufacturer about its solutions. Ask fellow contractors what they have found that works well. Among other frequent wishes are those for the ability to cut on the side without difficulty and some method of making the machine "load-sensitive." With today’s dozers, control is not difficult even when there is an uneven load on either side of the blade; that removes your anxiety about side-cutting. Komatsu’s load-sensing system is called CLSS (for closed-center load-sensing system), and it makes the lever stroke of the blade control directly proportional to the blade speed, regardless of the machine’s travel speed or load. In practical terms, a pressure compensation valve makes the operation more precise and responsive. For grading, where rework can be the most expensive mistake, the worry is always that the turning of the machine will put too much pressure on the ground and cause damage to already-worked surfaces. You avoid that problem when the inside track is not locked during turning. As contractors, we all know that frequent stops in any operation reduce productivity and profitability. Avoiding those stoppages is what we mean by smooth operation. With a dozer, that would mean starting its project and pushing through continuously until it is complete. If the operator can perform such functions as changing the blade’s position without stopping, the time saved will add up quickly. Deere’s H-Series crawler dozers have a counterrotation usable at any speed. This allows on-the-go repositioning and has been reported as helpful in avoiding those unwanted corner-loaded side drafts. Counterrotation, then, is a feature that will certainly help production, and several manufacturers offer it. (Don’t make assumption, though. If you want it, ask if the model you like offers that feature.) The operator need not shift into neutral to avoid stalling or limit the machine’s use to "good" ground conditions. On level ground or a 2:1 slope, the operator does not need to cross-clutch or ride a brake because the machine will not free-wheel.
Low ground pressure can be an advantage not only on muddy and wet terrain for house construction but also along streets built on ground where the water table is high. Hyundai offers its H70 in this configuration for smaller dozing work, with 72 fly-wheel hp. It can reach up to 7.3 mph in forward gear and 7.4 mph in reverse. The rated operating capacity of this Hyundai model is 15,540 lb., with a blade capacity of 1.81 yd.3 and a maximum drawbar pull of 27,780 lb. Recommended for precision work and grading, smaller dozers have designs for low operating costs and easy service. Among New Holland’s range of dozers are the DC150 and DC180, where the engine is matched to a torque converter and power-shift transmission with an automatic kickdown and automatic shifting to speed the loading and return cycles. You can also get a three-shank ripper, rear hydraulic function for a winch, and a rear PTO provision. The length of the track on the ground is another aspect of New Holland dozers that the manufacturer stresses as important to their ground pressure and weight distribution. Thill Track & Tractor Service in Eau Claire, WI, has more than 35 years’ experience in the repair and service of construction machinery. Owner Jim Thill believes there is one bad habit that owners of dozers have. "They don’t grease them. Regular maintenance is essential if you want your machines to do their best." It’s not difficult; it takes a few minutes and is too easy to skip. When your operator (or is it you?) climbs onto the dozer for the start of a day’s work, has he made sure that the correct daily inspections and maintenance have been done?
You need a BIG dozer? Caterpillar’s D11R gives you 850 hp from a Cat 3508B EUI engine (with a tank refill capacity of 425 gal. to keep you going). The electrohydraulic dozer and ripper controls are low effort and comfortable for the operator, with no mechanical linkages. For further ease of operation, some of the more common blade functions are semiautomated. The D11R also has AutoPitch, an automated blade feature similar to that of the D11R Carrydozer. The small and medium Caterpillar range of dozers goes from a gross power of 78 hp for the D3C models to 230 hp for the D7R. How heavy are they? At the start of the medium range, the D5M LGP (for low ground pressure) has an operating weight of 28,800 lb., while the D11R Carrydozer weighs in at 248,600 lb. (That’s the operating weight; shipping weight is less: 166,000 lb.) The largest dozers tend to be used for mining and quarry operations, where they are working all the time, rather than for general contracting. Constant, high productivity justifies their use and cost. At the other end of the scale are those dozer attachments for compact machines. We have seen a skid-steer loader do the necessary work quickly and evenly for site preparation at some developments for new apartments and shopping malls. One of the answers for the question "How big do you want your dozer?" is "As big as necessary to get the job done on schedule and profitably, and no bigger." When the dozing is really backfilling, there are many loaders and compact excavators that have a standard blade for such work. One of the most important aspects of new models of crawler dozers is the comfort of the operator. There are more than 20 dozers in the Komatsu line; those models designated with a "P" have a wider and/or longer undercarriage. The combination of joystick and simple foot-pedal controls gives low-effort, efficient operation of the dozers. Each dozer has a suspension-type seat that conforms to the operator’s weight, with an adjustable lumbar support for maximum comfort during the workday. These Plus Series dozers offer an easy-to-operate joystick system for precise steering and blade control. Directional changes are initiated by the steering control located at the operator’s left armrest, and steering commands are translated by a valve that modulates hydraulic pressure in direct proportion to the movement applied to the joystick control. Does your dozer distributor recommend a different kind of control? Ask other contractors what they think about that most important subject. Have they found unpublished snags with certain types of control? Ask operators what they think. Let your operator sit in the cab of a dozer before you decide if it’s what he needs. Quiz him about the visibility, convenience of controls, seat adjustability, and comfort. Ask how much it could improve production. Superior Production With Tracks
A deadly ice and snow storm pounded Arkansas on December 27, 2000. Two-inch-thick ice toppled trees, snapped power lines, and created a debris field throughout the entire state. After the first harrowing days of the disaster in which hundreds of thousands had no power, phone service, or water, the state turned to the task of cleaning up. With so much debris, contractors poured into the state, eager to help. Mark Mainquist, owner of Cynmar Environmental in Gretna, NE, was one of them. Mainquist had seen other disaster cleanup jobs. He had watched as wheeled machinery such as skid-steers and loaders had struggled. They could get the job done eventually, but they often had difficulty in pushing heavy debris, and their tires would spin and rip up property–adding injury to an already scarred landscape. When we saw the damage, we thought we had a way to do the work faster, easier, and without damaging property," says Mainquist. In his normal work (conducting erosion control efforts surrounding construction sites), Mainquist uses a Posi-Track 4810, manufactured by ASV (a Caterpillar affiliate). Equipped with a rubber-tracked undercarriage incorporating 48 wheeled contact points, its design transfers the weight of the machine to the ground, resulting in a low ground pressure of only 3 psi. "This was a good test to see if these new high-tech machines could improve how cleanup efforts are conducted," notes Mainquist. Armed with a 4810 and a Caterpillar Telehandler, his crew began in the city of Texarkana. Through the Arkansas Department of Emergency Management, Mainquist and other contractors had to remove tons of debris from streets, city parks, and residential yards. "There were a lot of us out there, but it suddenly became clear that we were able to move a significantly larger amount of material than those with skid-steers or conventional loaders," says Mainquist. "At the same time, we were not causing the same damage to property as other machines." With the Posi-Track, Mainquist found that he could push the debris like a bulldozer, without tires spinning or getting stuck. "It has such tractive power that we were pushing piles several times larger than what others could push; we were pushing mountains," he describes. "Our competitors were spinning tires, ripping up grass, getting stuck, wearing out tires–it was a mess." Mainquist’s technique also allowed him to conduct cleanup work in tight areas where others had difficulty. "When you’re pushing large debris in tight areas, such as in alleyways, it’s difficult to maneuver, but with the Posi-Track we could climb straight up onto a huge pile of debris, come down another side, and push from that direction." The Posi-Track would then move the debris to the street, where the Telehandler would scoop it up and place it in a truck to be removed. Finally, don’t write off those farm tractors as unsuitable for grading and excavation. Several companies have designed attachments for tractors that can help contractors complete jobs with profit and speed. Do you remember the article on trends in scrapers ("The Perfect Shape" in the January/February 2001 issue)? Even the established makers of integrated scrapers and graders are realizing that the combination of a "farm" tractor and a pull-along scraper or grader can be much less expensive and just as effective as the traditional equipment. Such names as Reynolds, Deere, Glenmac, Prime Manufacturing, and Caterpillar come to mind for these solutions. Paul Hull is a frequent contributor to Grading & Excavation Contractor magazine.
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