Earlier this year, Great Dane Trailers, Louisville, KY, introduced its own liner variation, called ThermoGuard. It is a new one-piece, glass-reinforced, thermoplastic liner that company officials say can potentially reduce cooling unit run time by about 1,000 hours over five years.
ThermoGuard linings “will improve fuel economy almost immediately, within two to three years at least,” says Charles Fetz, vice president of research and design at Great Dane. “It’s something that’s taken us several years to develop, but over a long period of time, you will see real benefits.”
“Reefer owners have always been in a race against time to get the most usefulness out of their trailers before the insulation got too old,” says Phill Pines, chief operating officer at Great Dane. “Until now, the only way to compensate for the decreasing insulation performance has been to make sure the cooling unit had enough excess capacity to maintain temperatures over the course of time.”
Now, the options are much greater. “Everybody is making their trailers better,” Utility’s Cole notes. “There’s a much higher content of glass-lined and composite materials that are stronger, more durable and more impervious to damage, moisture and heat transfer.”
To that end, Johnson Truck Bodies devised a seamless fiberglass ArcticTherm interior liner that company officials claim offers a 26 percent improvement in thermal efficiency compared to other liners.
“We keep trying to improve on our processes, including the foaming materials and liners,” says Huerth. “We’ve found that fiberglass gives us another advantage—we can seal floors, walls and ceilings seamlessly in a one-piece liner that has no junctures for water to build up. It gives us both a strength advantage and a cleaning advantage.”
Regardless of what they’re made of, though, “one-piece liners have quickly be-come the industry standard for cleanliness, attractiveness and durability, and there are no seams for water to get into them,” says Great Dane’s Fetz.
Moisture is also a big factor for a number of reasons, least of which is that it causes the insulating materials to break down more quickly. “Water expands when it gets cold, and when it gets inside the linings, it causes a breaking of the foam cells and allows essential gasses to move and escape, he continues. “Getting the trailer sealed up properly against moisture is the key to its long-term longevity.”