Spec’ing Trailers: The Devil’s In The Details (February 01, 2010)
February 1, 2010
By Ingrid Phaneuf TORONTO, Ont. - When it comes to spec'ing trailers you've got it down, right? After all, what's so complicated about a box on wheels? Lots. Spec'ing your trailers right is just one m...
By Ingrid Phaneuf TORONTO, Ont. –When it comes to spec’ing trailers you’ve got it down, right? After all, what’s so complicated about a box on wheels? Lots. Spec’ing your trailers right is just one more, very important way to reduce operating costs and incidents and add zeros to your bottom line.
Weight, of course, is a prime consideration, “but nowadays most manufacturers are within a couple hundred pounds of each other,” says Mike Hignett, equipment account manager at Glasvan Great Dane. “Basically you can achieve weight savings by using thinner materials, but that has its disadvantages too, as far as the life span of your trailer goes. Most of our customers want their trailers to last as long as possible -they don’t want to have to retire a trailer after five to seven years because it’s so much lighter that it wore out. There’s no point buying two trailers over a 20-year span when you can buy one.”
That said, technology is making both durability and lightness a possibility.
“We’ve see new composite material for sidewalls over the last 10 years, that are a lot more durable because there’s no use of wood, provide more space inside the van and therefore allow carriers to load more material and do less damage when it comes to unloading,” says Hignett.
Wear and tear
Corrosion is a major consideration trailer purchasers must take into account as well.
“Corrosion, especially with the stuff they’re putting on the roads to get rid of ice now, is something that’s on everyone’s minds,” says Hignett.
Special undercoatings can provide some protection for what’s under the trailer, but the use of mixed materials also poses a risk, Hignett says.
“It’s not just the stuff they put on the roads that causes corrosion, but the way metals react to each other,” he explains. “Electrolysis (when different metals touch) is a factor. If you have dissimilar metals contacting each other and moisture gets in, corrosion can start.”
Metals that react to each other in this way must be insulated, Hignett says.
“You combat it by putting an insulator between them so they’re not touching. We use a double thick mylar between dissimilar metals to prevent corrosion.”
Corrosion is also why many clients are moving away from painted steel components and opting for galvanized or stainless instead, he says. Corrosion of steel components can be further hindered by spray-on coatings, he adds, pointing out any corrosion on a tractor or trailer is a major red flag for roadside inspectors.
Doors and floors deserve special attention, Hignett adds.
“Most door manufacturers will now use a composite panel with aluminum on the outside and aluminum or steel on the inside instead of traditional wood,” he says. “That way no water is absorbed and rust is avoided.”
As for dry van floors, they are particularly vulnerable to wear and tear whether they’re rolling down the road or sitting in the yard. While the underside of flooring has to endure road spray, the top side suffers from stress caused by weight and by the doors being left open when the trailer is in the yard.
Prolam, based in Quebec, manufactures dry van floors that are specially-designed to endure all three kinds of punishment, according to Benoit Risi, the company’s director general.
Zigzag joints for wood laminate flooring are used instead of hook joints to reduce stress from weight transfer, Risi says.
“Hook joint floors are weaker and they may need putty,” he explains. “But our double knuckle zigzag joints are tighter and stronger.”
Tight, strong joints are a serious issue when you consider that the wood laminate floor of a single trailer can have anywhere between 880 to 2,000 joints, and is continually being exposed to moisture and shifting weight, Risi points out.
Undercoating further prolongs the life of trailer floors.
“We have developed a new, hot-melt polyurethane reactive (PUR) coating for the underside of floors,” says Risi, adding the polyurethane coating lasts longer than water-based coatings. “I sold my first trailer with PUR four years ago and it’s still shiny underneath,” Risi says.
Another innovation is the introduction of top-of-floor coatings to protect the floor near the rear of the trailer from snow and rain. Trailers are most often left in yards with their doors wide open, points out Risi, “which means you get a lot of deterioration of the last eight feet of the floor surface. That’s why we impregnate the last eight feet with melted paraphen wax so that when it all comes back to room temperature you have solid paraphen through the first 1/8″ thickness of the surface. Water just can’t get in.”
Risi’s advice to trailer spec’ers is this: Pay attention to the quality of the parts you pick. “There are a lot of producers out there. Some are okay and some are better,” says Risi.
Tankers: Inside and out
Of course not all trailer spec’ers are looking to buy dry vans, which means there are even more considerations to take into account than those already mentioned.
For example, knowing how what you’re hauling will impact the inside of your tanker is essential, says Kevin Brown, account manager for Tankmart International.
“A lot of people have a misunderstanding of what you can do with stainless steel tanks. I’ve got two tanks in my yard right now belonging to people who were convinced that there wasn’t any problem with the product going in them,” he says.
“For instance, it’s true that you can haul something with sulfuric acid in stainless, but it depends on the concentration.”
That’s why it’s important to know exactly what you’re going to be hauling not only before you buy a tanker but every time you haul, says Brown.
LCVs: Double the trouble
LCVs not only require twice the consideration that goes into purchasing a single trailer, but are also governed by a whole other set of regulations.
Of course, they’re ideal for carriers who want to cube out instead of weigh out, but that doesn’t mean you should make your decision to invest in an LCV configuration lightly, says Dave Mizgala, chief engineer for Di-Mond Trailers.
Buyers first have to consider whether to opt for anA-or B-train configuration, Mizgala says. Regulations govern the length and weight of LCVs, so longer (an Atrain) isn’t always better. “A-trains have dollies, while B-trains have fifth wheels, and some carriers just don’t want another dolly to worry about,” says Mizgala.
Electrical systems on both Aand B-trains are also a consideration given their increased power consumption.
“It’s a good idea to spec’ with LEDs over incandescent lamps because it will reduce power consumption,” advises Mizgala.
Both trailers should be hooked up to the tractor via a separate harness, he adds. “Studies have shown that if you splice another harness into the lead harness you can overload the circuit at the rear (are you reading this retrofitters?) and short out the back trailer. The splicing isn’t illegal but it’s not a recommended practice, Mizgala says.
Cost versus durability is also a consideration, for example disc brakes may be easier to maintain and last longer, but they also cost a whole lot more up-front.
Of course, most of your buying decisions, when it comes to LCVs, will be dictated by the rules and regulations of the places you haul. A decent dealer should be able to tell you exactly what these are, says Mizgala.
Indeed, for any trailer purchase, a knowledgeable dealer is essential, industry insiders agree.
“A good OE will ask you where you’re going and tell you what the type of vehicle you can work with depending on the jurisdictions you haul through,” says Mizgala.
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