Wheel tractor scrapers will never become obsolete. They fill a niche in earthmoving that no other machine can compete with. For short distance bulk earthmoving they’re lower cost and faster than any other haulage unit.
Over the last few years ADT’s have become popular in the United States. Contractors leaned heavily towards utilizing ADT’s largely due to the fact they require no skill from the operators who run them. The reason that contractors have leaned this way is due, in my opinion, because the operators in this industry have drastically changed over the last 40 years.
In the 1960’s and 1970’s, during the heyday of big dirt when large scale infrastructure and other projects in the US involved tremendous quantities of earth to be moved, this industry held a class of operators who possessed true skill as scraper, dozer and blade hands. The scraper hands (and other operators) you had at that time were overall, much more skilled than we have today. At that time, operators were able to spend enough time in the seat of a scraper, on large earthmoving projects to really see that the learning curve on a scraper isn’t nearly as flat as “scraper operators” these days think it is.
Take Deeretime’s above post as an example; too young and too inexperienced to know what scrapers are capable of, therefore a false conclusion is drawn about what is needed and required of a scraper hand.
Twenty to thirty years ago, you were dealing with an era of operators and supervisors who actually knew how to run a scraper spread. Bladehands who actually knew how to work with and ahead of the scrapers they were supporting. Dozer hands who knew how to support a scraper cut and push-cat hands who knew how to properly run a cut. Dirt bosses of that time didn’t earn a seat in a pickup because they just graduated as construction managers or hired on as P.E. interns. They spent time as operators and grade setters and worked their way into the position as a dirt boss once they’d earned it.
These days it’s a rare case that a crew running a scraper spread consists of anyone who has multi-millions of cubic yards of material under their belt supervising scrapers. This lack of experience has lead to improperly running the operation, which has directly fostered the widespread negative attitude towards scrapers. It’s damn hard to fill the seat of a scraper with an operator who doesn’t have a lot of bad habits developed from running scraper for a company/crew/dirt boss who didn’t know what they were doing. It’s getting even harder to find operators who know how to properly support scrapers. I’ve hired blade operators who were excellent finish hands. But when they’re put on a blade to work with/ahead of a spread of scrapers they can mess things up and do more harm than no grader at all in short order.
This is largely stemmed from being able to find a lot of operators who’ve not been around scrapers, or operators who didn’t get a chance to be around the “old school” of operators and dirt bosses who knew how to actually run scraper spreads.
It doesn’t take long before enough of these factors, bad operators, rough haul roads, poorly run jobs, etc., that contractors started leaning heavily towards ADT’s. Scrapers by nature move material fast, and it takes a skilled crew and supervision to build cuts and fills with scrapers that don’t get over cut or over filled, which leads to a lot of expensive time spent fixing the mistakes made by the poor operators and supervisors. With ADT’s, things move much more slowly and in a controlled manner that allows any idiot to build things correctly.
This factor compounds itself by creating a whole lot of scraper operators these days that, without any other way of putting it, don’t deserve the title of operator.
So, as scrapers get a bad reputation because it takes skill and experience that most of today’s “dirt bosses” do not have or have the ability to train, the market is ripe for any easier way out, which has been via ADT’s. It’s even to the point where CAT/dealers are having to publish memo’s to educate contractors that ADT’s are not “rock trucks,” as contractors are utilizing ADT’s in rocky material and conditions suited for rigid frame trucks, where the ADT has become the cure-all answer for dumbass earthmoving.
So talking about the wheel tractor scraper becoming an obsolete machine is asinine. It will always fill a role that no other machine can. The change in their utilization is because without the class of true operators that this industry used to have, you will never see scrapers utilized in the same manner, or nearly as efficiently as they once were.