MAJOR trailer fleets have bought DuraPlate dry-freight van trailers by the thousands in a relentless search to get a bigger inside from a box that has its outside dimensions defined by federal size and weight laws.
Wabash National, the company that pioneered the use of DuraPlate in the trailer industry, has been seeking other applications for its composite sidewall material.
The van body market was a logical place to turn. But initial results did not come close to meeting the high volumes of production to which the trailer manufacturer had grown accustomed — at least until its van body partner, Utilimaster, began producing a design that bonded the DuraPlate panels together. The company recently completed its first major order for bonded DuraPlate van bodies and has begun its second.
Utilimaster, a truck body manufacturer based in Wakarusa, Indiana, has an agreement with Wabash National that allows Utilimaster to use DuraPlate in truck body applications. Under the agreement, Wabash National supplies Utilimaster with 4'×8' DuraPlate panels that Utilimaster uses to produce van bodies.
As with any standard van body (or trailer) design, Utilimaster's design has top and bottom rails, along with front and rear corner posts, to hold its side panels in place and provide rigidity and load support to the body. But where Wabash National uses rivets to secure the individual DuraPlate panels to one another, Utilimaster uses an adhesive to bond the panels together.
The result was a design that combines the strength of DuraPlate panels with the aesthetics of FRP plywood.
“With bonding, we are much closer to having a seamless sidewall,” says Tony Gray, manufacturing manager for Utilimaster's truck body fleet. “The joints are flat and with no rivet heads along the seams, decals can be applied easily.”
Initially work with DuraPlate truck bodies involved using rivets to secure the panels to each other.
“Once we began bonding them, we generated a lot of interest,” Gray says.
Truck body applications — even 24-ft-long vans — can rely on a subframe and the frame rails of the truck chassis for additional support. As a result, the panels are subjected to less stress than if the panels were used in a 53' van trailer with monocoque construction.
Research and development
With several orders for bonded bodies, Utilimaster has begun experiencing the fruit of an extensive research and development program to bring out a DuraPlate van body and uses adhesives.
“We couldn't just swap a DuraPlate panel for one made of FRP plywood,” Gray says. “They are two different materials, and they react differently to the stresses that van bodies experience.”
In developing the concept for a bonded van body, Utilimaster conducted tests in the lab, followed by durability testing of the prototype.
“We tested bodies held together with buck rivets, with a variety of adhesives, and with a combination of rivets and adhesives,” Gray says. “We conducted a series of cycle tests, driving the samples to failure and then examined the differences at failure.”
Durability testing included running prototypes on a track and using computer modeling to enhance the design.
First in line
Budget Truck Rental was the first large fleet delivery with the bonded design. Utilimaster started production in May and by June had completed the 450 bonded van bodies.
The bonded vans were part of an order for 2,100 van bodies — a mixture of FRP plywood and DuraPlate panels. Included in the mix were 835 vans 16' long and 1,265 that were 24' models. Among the FRP vans, the panels were 3/8;" thick when used on 16' vans and measured 1/2;" thick for 24-ft-long vans.
By contrast, the DuraPlate vans used 6 mm thick (.236") material, regardless of whether the bodies were 16' or 24' long. The panels used in the Budget order bonded .013” steel skins on both sides of the composite core material. This is slightly thinner than the .019" skins that Wabash National typically uses to produce its DuraPlate van trailers.
“The 6 mm material provides more cargo capacity with reduced tare weight,” Gray says. “And we have flexibility with the thickness of the skin and the core material. We can dial in a DuraPlate panel that matches the application.”
Utilimaster finished the last of the 2,100 trucks during the first week of June, slightly ahead of Budget's schedule.
Delivering the mail
The slogan at the United States Postal Service may be “We deliver for you,” but the roles are reversed at Utilimaster, where the company is in the process of delivering to the United States Postal Service more than 2,000 trucks equipped with bonded DuraPlate van bodies
Utilimaster quickly switched over production to the United States Postal Service trucks following the completion of the Budget order. Under the terms of the contract, International and Freightliner are the prime contractors, with Utilimaster serving as a subcontractor.
Under the terms of the contract, Utilimaster will produce and install 17' and 24' bonded DuraPlate van bodies on International 4400 conventional chassis and Freightliner SC-8000 cabovers. The United States Postal Service specified 7.5mm thick DuraPlate panels with (.019") skins.
The United States Postal Service based its purchasing decision in part on the success it has had with its DuraPlate dry-freight trailers. In 1998, Wabash National had received a large order from the United States Postal Service for FRP van trailers. Toward the end of the production run, the manufacturer convinced the United States Postal Service to accept some DuraPlate vans on a trial basis.
“The United States Postal Service placed them in service in Indianapolis, fairly close to Wabash National headquarters in Lafayette, Indiana,” Gray says. “After a lengthy trial, the United States Postal Service found that its DuraPlate trailers had the lowest maintenance cost of any group of trailers in the fleet.”
Utilimaster is scheduled to complete the order for 2,014 van bodies in January 2005.
Trucks will be equipped with Truck-Lite's LED pod light package, heavy-duty oak floors, galvaneal rear door frames, and a little high tech: backup cameras to let the driver know where he is when backing, and XATA Fleet Management Systems.
About half of the trucks will be equipped with liftgates. Four manufacturers will provide the liftgates, in part because of the variety of environments in which they will operate.
“The trucks that will go to Alaska, for example, will be equipped with liftgates that have power down,” Gray says. “As cold as it gets there, you have to have power down.”
All bodies and equipment will be installed at Utilimaster's Wakarusa location and shipped to the local United States Postal Service operating point.
An order as large as Utilimaster's United States Postal Service job requires a cooperative effort.
“It's really about convincing the chassis manufacturer or truck dealer and the end customer,” Gray says of his company's efforts to sell something as different as bonded DuraPlate bodies to major customers. “After all, it took Wabash National only six years to obtain 25% market share with DuraPlate in dry freight trailers.”
Suppliers also play a key role.
“We have been working with Wabash National for the past few years,” says Jim Orbik, Utilimaster's vice-president of operations. “Our two companies have a lot in common beyond the fact that we both are based in Indiana. Both of us emphasize innovation and are quality driven. Utilimaster's engineering, paint, purchasing, and contract management operations are all QS 9000. In November, we certified our walk-in van product to ISO 9001:2000.”
The relationship has given Utilimaster a little something extra to sell.
“Riveted sheet and post bodies are proven technology, and we will continue offering vans with a wide range of designs,” Orbik says. “But we view this bonded DuraPlate design as an important extension of our product line — something that will become increasingly popular as more customers gain experience with it.”