Flexibility is the key to your scraper toolbox as one size doesn't fit all applications.
From site to site and soil to soil, there is no one scraper that will tackle every job. Even though some units are touted as moving everything but the Rock of Gibraltar, contractors are left, often through trial and error, to make the choices that truly lowers their per yard costs. Veteran operators say that scraper use is all about live-and-learn application sensitivity. Success with one tool versus another can be surprising. What may be assumed to be an unequaled earthmover could end up a mere stick-in-the mud performer when encountering less-than-ideal conditions. When sizing up any type of scraper, you need to sift through myths, misconceptions, and legends. Flexibility, along with an open mind, is definitely recommended.
From self-propelled scrapers to pull-types and their power sources, there are many models on the market. With that said, let’s take a closer look into the scraper toolbox as several manufacturers and contractors offer their individual (and sometimes conflicting) takes on scraper solutions for a variety of soil types.
Caterpillar
Caterpillar says that the wheel tractor-scraper is one of the most cost-effective earthmoving systems because of its fast loading cycles, 34-mile-per-hour road speeds, and an ability to dump on the run. Other advantages, says Caterpillar, are its ground clearance and low center of gravity, which mining and waste industry users count on as they negotiate grades of 30-degrees or more, usually in off-road type terrain.
As to wheel tractor-scraper advantages over towed scrapers, Caterpillar points to an ability to work in a variety of materials and the capability to dig down through varying types of horizons such as nice topsoil, to clay, to clay with rock, and to rock. Its units are engineered for high loads, with frames and structures that are durable well into 50,000 hours, says the company.
In prime topsoil, or in super wet or sandy conditions where rock is minimal, Caterpillar says that a Challenger tractor pulling ejector scrapers offers flotation and the ability to run where the self-propelled unit may not.
While Caterpillar stresses that there is a time and a place for both wheel tractor-scrapers and towed scrapers, careful consideration should be given to materials and job constraints such as turning radius. There is a risk, they say, in push loading a towed scraper as the stresses to the tractor’s hitch and axles may be damaged.
Lastly, Caterpillar says that the heritage of the towed scraper is that of a topsoil earthmover predominantly in agricultural applications. As such, when put into construction applications where more than topsoil is being moved, agricultural tractors can fall short in terms of component durability and rubber track life. They go on to say that unless equipped with brake systems, towed scrapers may not be viable for projects without good haul roads, or those with steep slopes and the need for high-speed turns.
Expressing a commitment to its wheel tractor-scraper line, Caterpillar says that it continues to engineer its units with new technology, comfort features, and productivity gains. CONEXPO 2008 will see Caterpillar unveil its new 613G elevating scraper which will begin production in September of this year.
The company says that among other improvements, the new unit offers increased rimpull, faster elevator speeds for a quicker loading cycle, and a larger cab with more comfort amenities.
From job startup to final cleanup, Caterpillar says the new 613G is designed to serve many roles, such as stripping light vegetation, conditioning topsoil for later reuse, and leveling pads and cleaning up the final grade, while laying down precise lifts that allow compaction control. On road jobs, the unit will remove motor grader windrows, contour ditches, and lay down base material.
The rest of the Caterpillar wheel tractor-scraper line includes the 623G, its largest elevating scraper which is popular in landfills, medium to large housing and commercial developments, and on road construction; its 621G and 631G Tier-3 open bowl, push-loaded models designed for earthmoving on short to long hauls of a mile or more; and its 627, 637, and 657G twin-engine models for applications such as mines, quarries, dams, airports, and other commercial jobs.
Terex Construction Americas
Terex currently offers one key self-propelled scraper model—its TS14G—a twin-engine, 352-horsepower unit with 20-cubic-yard heaped capacity. Ken Emmett, Terex product manager for articulated trucks, rigid trucks, and scrapers, says that his company has manufactured more than 11,000 of these units, and has chosen to focus on this model as it is an affordable, yet powerful twin-engine machine. “Many contractors think that they cannot afford a twin-engine machine and that they cannot cost-effectively move dirt with it, but that is simply not the case with our unit. The TS14G offers similar horsepower as a competitive single-engine scraper, but because our unit is twin-engine and all-wheel drive, it will go where the comparable model will not go—and will do it at approximately half the capital cost,” he says, elaborating on the misconception that self-propelled scrapers cannot operate in soft-bottom conditions. “Our units are used quite often in areas where you might have mud that will not support the weight of heavier, comparable scrapers. Our twin-engine scraper gets that horsepower down to the ground, spreads it between both ends, and allows the machine to go where other units won’t,” he says.
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| The Terex TS14G is a self-propelled, twin-engine scraper with 352-horsepower and a 20-cubic-yard heaped capacity. |
Emmett says that because contractors assume it costs too much to buy a twin-engine scraper (in the 14- to 16-yard struck capacity class), that they will then turn to the less expensive alternative, which is a pull pan with a “farm tractor,” he says. “By doing that, you give up the life expectancy of our twin-engine scrapers, as farm equipment is made to run considerably less hours per day. So the longevity of the pull-type scraper is not that of the power scraper,” he says.
As to the industrial power units for pull-type scrapers, Emmett says, “I think it remains to be seen whether they have industrialized them enough. When you put two and three pull pans behind them, you have traction problems with the tractor. The solution could be going with tracks, but then you have the downside of higher maintenance costs,” he says.
Emmett agrees that there is definitely a place for the pull-type scraper; however he says, “On jobs highly suitable to the power scraper, there are only a few things that move dirt cheaper: an earthquake, explosives, or a dragline.”
Ashland Industries
In addition to offering the only track loader scraper available on the market, the Ashland Industries product line includes a complete selection of pull-type ejector and dump-style earthmovers with dirt pans to fit any horsepower range, says the company.
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| Ashland's CS18-HD Carry-All Scraper is the industry's heaviest duty offering in the18-cubic-yard capacity class of all carry-all scrapers. |
Ashland Industries recently signed an agreement to package its I-180TS2 ejector-class scrapers with a new dedicated scraper hauler manufactured by Volvo—a new offering that is currently in limited production and will be unveiled at CONEXPO 2008.
“With the new Volvo scraper hauler in combination with our scrapers, contractors will have the comfort level that they will be operating a true industrial-designed package from the ground up, rather than a power unit that is repackaged from an agricultural-based application. Our scrapers will also have integrated brake systems and other features that will make this combination a total, complete industrial package,” says Randy Rust, president of Ashland Industries.
Richard Iddins, Volvo sales engineer for the hauler/loader line, says that when the new scraper hauler project was started, the initial decision was not to align with any particular scraper manufacturer. “But then we learned that there is a huge difference in the scraper market, and we wanted the optimum package of a hauler and a scraper,” says Iddins who stresses that the initial purchase price, operating cost, maintenance, and fuel consumption on the new package is much less that that of a conventional power scraper.
As to cost per yard, Iddins says, “In the right application, we’re seeing numbers in the 40-cent range. Another factor is that the new scraper hauler is designed and built to last 10,000-hours-plus—where the agricultural tractor is often traded in at about 4,000 hours. So it’s a package that’s built for use over the long run,” he says.
At CONEXPO 2008, Ashland will also introduce its new CS18-HD Carry-All Scraper. Weighing in at nearly 25,000 pounds, the company says that the new model is the industry’s heaviest duty offering in the 18-cubic-yard-capacity class of carry-all scrapers.
“We talked with a lot of contractors and felt there was a need for a heavier-duty, dump-style scraper. We designed the CS18-HD to take on the toughest applications and material types. It’s a heavier machine that gives contractors ejector-grade durability in a dump-style format—allowing contractors to move more dirt at lower costs per yard, and with greater reliability,” says Rust.
Hoffman Construction, one of the largest earthmoving contractors in Wisconsin, recently used four CS18-HD scrapers to assist in putting in a liner on a landfill cell.
Familiar with conventional scrapers, the company had never used pull-type scrapers before, assuming that they would not be durable enough. “Pulled by a track-mounted unit, the scrapers really did a good job for us. We were running in wet clay at about 18% moisture. DNR specifications required us to eliminate any rutting and the scrapers allowed us to do that where conventional scrapers would not,” says Hoffman Construction Foreman Gary Widiker.
“I was operating a grader on the site and could hardly get through the material, while these scrapers self loaded right along side of me, hauled the material where it needed to go, and easily dumped it in the cell,” he adds.
K-Tec Earthmovers
K-Tec Earthmovers Inc., located in Manitoba, is a relatively new kid on the block. Founder Ken Rempel started a construction company and moved dirt for years in the Red River Valley. After operating many scrapers, he was not satisfied with their production capabilities and decided to design his own. He went into full scale production in 2004. The company currently manufactures a full line of pull pan scrapers, with its K-Tec 1453 being the largest pull pan on the market, offering a 53-cubic-yard capacity.
Rempel says that K-Tec units feature the advantages of light overall weight, high-tensile plate construction, reduced maintenance requirements, and more tires on the ground for better flotation. “Our scrapers are designed to prevent overload to the tractor. We can get equal amounts of weight on the back axle of a tractor pulling a 30- to 40-yard scraper as that incurred pulling an 18-yard scraper. So, we offer more payload with less wear and tear on the power unit,” says Rempel. “We also offer the largest gate opening in the industry, and that’s very important when working in mud where you can get a lot of material loaded but you can’t get it out,” he adds.
As to applications, Rempel says that the cost of tractor/scraper use is very competitive, especially in a dirt haul where many articulated or rigid rock trucks are now used. “You are often looking at half the cost per yard, and up to 30% less fuel consumption—and the longevity of the scraper is equal to any other motor scraper. As to the pull-pan tractor, its longevity depends upon the particular manufacturer. As to limitations, if it gets too rocky for a self-propelled unit, then it’s probably too rocky for our units—and then you would want to switch to a rock truck,” he says.
Nick Kostecki, owner of Spencer, OH–based Kostecki Excavation, is using K-Tec 1225 scrapers (25-cubic-yard capacity) pulled by track-mounted Cat Challengers on a long-term road project that involves more than 600,000 yards of earthwork. Kostecki says that he likes the fact that he can haul larger volumes without having to haul two scrapers. “Other pull pans are so much smaller, so you have to pull two of them to be efficient. That makes it harder to get around and the operators are always tearing them up. The K-Tec large-capacity units load so easy and are a perfect match for the tractors,” he says. “We’re also operating at lower costs per yard than conventional scrapers,” he adds, estimating his costs at 50 to 60 cents per yard.
Chris Galloway of CGC Construction in Davis, CA, has used a K-Tec 3100, a 31-cubic-yard-capacity unit, for more than 18 months. His company concentrates on wildlife habitat restoration and land leveling for rice fields. “We are seeing the same costs per hour of operation with the 31-yard unit as we were seeing with an 18-yard unit, so our profit per hour has gone up more than 30% due to capacity,” says Galloway.
As to soil types, Galloway says they can run well in anything from hard sand to heavy clay. “One of the nice things is that we can go through really wet material—stuff you can’t even walk through. The flotation is so much better than anything else out there,” he says, a factor he attributes to the unit being balanced. “The four tires on the back mean that there is so much more square footage on the ground to displace the load. Where other contractors, with smaller scrapers and lighter tractors would get stuck, we would drive right through carrying twice the material,” he says.
Miskin Scraper Works
Miskin Scraper Works was founded in 1917, when scrapers were pulled by horses, says the company, which today offers more than 25 ejector and dump-style scraper models. Miskin will introduce its new E-20 (20-cubic-yard capacity) ejector scraper at CONEXPO 2008.
Miskin Eastern Regional Manager Mike McCrory says that it’s all about volume. “You’ve got one operator and one tractor, and he can haul either one, two, or three 20-yard scrapers, giving him up to 60-yards of material being hauled. There is nothing else on the market that will move that much material with only one operator,” says McCrory, who adds that another big advantage comes from the pull scraper system’s ability to work without support equipment. “It loads and unloads itself while dumping on grade without the need for a crawler dozer to smooth out the dump area.”
As to when to use an ejector over a dump-style scraper, McCrory says, “There are basically two times when you need to pull an ejector scraper—and that is when you are trying to dump on grade and you’ve got to have a fixed cutting edge; and the other time is when you’re working in very sticky clay or gummy mud. In that case, the ejector cleans out the bowl better than a rollout dump does.”
However, McCrory stresses that their models have addressed the common problems seen in typical scraper use.
“With our D-Series (dump-style), we can dump on grade and do have a fixed cutting edge, so that makes our unit more universal than others. We do run into the same problems with heavy, sticky dirt that any other dump-style units do—but we can now address that issue with our new Ejector-20 model,” he says.
The Right Tool for the Task
Like any other equipment type, it’s always about choosing the right tool for the application. While ejectors perform better in heavier clays, dump-style units are the choice for sand. When the ground is hard, self-propelled scrapers have an advantage. The important thing to remember is that many scraper manufacturers are pushing their technologies to the next level. So take a closer look at the total scraper toolbox—you may find yourself sizing up a few new solutions.
Writer and consultant Carol Wasson owns JCL Marketing & Communications Inc.
GEC - March/April 2008