Industrial Management: Materials
In Transportation, One Word: Plastics
Durable, light, and inexpensive, composites are the stuff of buses and even bridges
Not too far down the road, you may hop aboard a city bus that crosses over a major urban bridge--and both will be made of plastic. In fact, the first plastic bus is already in service at Boston's Logan Airport. Shuttling between terminals, it has a 30-foot-long body of fiber-reinforced plastics made by TPI Composites Inc. in Warren, R.I. The usual welded-steel frame has been relegated to the scrap heap. Except for the engine, just about everything above the axles is a plastic-and-fiberglass material.
Reinforced-plastics bridges are starting to pop up, too. Around the country, some 20 bridges now have composite-plastic roadways--including a four-laner in downtown Dayton, Ohio, that has just reopened to traffic. Ohio plans to use composites to restore 100 bridges around the state. And steel could become passe for bridges as well as bus bodies. Near Glasgow, Del., on State Route 896, there's a no-steel bridge built by Hardcore Composites Inc. in New Castle, Del., a spin-off of DuPont.BREAKTHROUGH. A common thread links these innovations: the vision of Martin S. Grimnes, a former manager in Maine's textile industry. Around 1980, with offshore competition intensifying in textiles, he urged his then-employer, W.S. Libbey Co., a maker of textile-weaving equipment, to diversify into glass fibers for plastic composites. When Libbey didn't buy his scheme, Grimnes in 1985 founded Brunswick Technologies Inc. (BTI) in Brunswick, Me.
BTI's big breakthrough was 10 years in the making--or rather, the unmaking. Initially, the company produced fabrics woven like ordinary cloth but with carbon or glass fibers instead of cotton or wool--an approach used by many other manufacturers of reinforcing fabrics. This fabric is used to line a mold, and hot plastic is injected to encapsulate the fibers. It's one way of making skateboards, truck panels, and boats.
Then Grimnes decided to unweave the fabric. Instead of looping the glass strands over and under each other, the fibers are stitched together where they cross. This simple change yielded two big benefits: First, the fibers no longer had to cross at right angles, so BTI could tailor fabric reinforcements that concentrate their strength in specific directions. For instance, there's a "tri-axial" fabric with 80% of the fibers running lengthwise, and the rest criss-crossing the main fibers at two different angles. This proved invaluable for such things as the 157-foot-long blades on huge wind-power turbines from Zond Energy Systems Inc. in Tehachapi, Calif. In addition, BTI's new stitch-bonding equipment can make fabrics that are thicker and heavier, and thus stronger, than the competition's--just the ticket for buses and bridges. BTI unveiled the new glass-fiber fabric in 1995, dubbing it White Steel. Last year came a carbon-fiber version called Black Steel.
The ability to orient the strength in specific directions is crucial to TPI's composite bus. The company is famous for producing big yachts and boats, molded in one piece, that shrug off the pounding seas. But city buses take a different kind of pounding on the street, introducing new stresses and strains, says Stephen A. Misencik, TPI's director of design engineering. "We gave BTI the specs, and they delivered the material almost the next day."
When executives from North American Bus Industries Inc. (NABI) saw the results, they bought the exclusive rights to the composite bus, lock, stock, and barrel. NABI is a relative newcomer to the U.S. bus business. It delivered 500 buses last year for a 10% market share, assembled in Anniston, Ala., with welded-steel bodies shipped from Budapest, where the company has its headquarters. When NABI puts its CompoBus into production late this year, TPI will ship its one-piece mouldings to Alabama. William H. Coryell III, NABI's vice-president for sales, says he already has two orders in hand--from Phoenix and Santa Monica, Calif.--for at least 50 buses, in various sizes up to the new 45-foot length.SHAKEUP. The first CompoBus is slated to head for Santa Monica early next year. Prices will probably start at about 10% more than the average cost of $275,000 for a city bus, but as production grows, "we hope to get that down to very near the same," says Coryell. Initial pricing is still uncertain because transit buses must pass a rigorous test to qualify for an 80% federal subsidy. One TPI prototype is on the final legs of the required 39,000 trips around a Transportation Dept. obstacle course in Altoona, Pa., operated by Pennsylvania State University. Another prototype is sitting on a huge simulator at Ortech Corp. in Mississauga, Ont., near Toronto. The simulator has been programmed with recordings of a bus lurching and bumping along some of the worst streets in New York City. "It's shaking the ever-loving hell out of the bus, day and night," to simulate 500,000 miles of urban travel, says Coryell. "I expect we'll learn some things that will require some changes," he adds.
Even a premium price probably will not deter the appeal of the composite bus, because it can save a bundle in city-transit operating costs. The plastic body slashes overall weight by 6,000 to 7,000 pounds. That means a smaller diesel engine can be used, which improves fuel mileage--or makes it more feasible to use a hybrid electric-diesel system. NABI is also developing essentially pollution-free models that burn hydrogen gas. The lighter weight also cuts down on wear and tear, so NABI expects a composite bus to stay in service a few years longer than the current 12 to 15 years.
To Hardcore Composites, BTI's stitch-bonded fabrics are the lifeblood of its business. "We couldn't be succeeding without them," says Hardcore Vice-President W. Scott Hemphill. "Infrastructure projects [such as bridges] are all we do," he notes. Before White Steel was introduced five years ago, "our revenues were close to zero because you had to give our stuff away to get people to use composites for infrastructure," he says. Since then, "growth has been explosive." Last year's revenues climbed to $10 million, says Hemphill.
The long-term outlook is even brighter. Hardcore won the job of overseeing the repair of 100 bridges in Ohio from the Ohio Development Dept., a contract worth roughly $20 million over the next four to six years. The first installation is slated for March. Ohio wants this program to help foster a statewide composites industry.
Hardcore is also involved in resurfacing Dayton's Salem Avenue bridge--perhaps the world's biggest composite plastics roadway. But it's not the only supplier. The Ohio Transportation Dept. (ODOT) picked four companies to install the composites roadway. Besides Hardcore, there's Composite Deck Solutions in Dayton; Creative Pultrusions Inc. in Alum Creek, Pa.; and Infrastructure Composites Inc. in San Diego. Each company is responsible for one-quarter of the 680-foot-long, 96-foot-wide bridge. For BTI, the Dayton bridge marks a tour-de-force performance. "All four companies are using our materials," gloats Grimnes.
Ohio's emergence as the plastics bridge-building capital of the world is the fruit of a six-year struggle by Steven E. Morton, an ODOT structural engineer, which began after he took a course in aerospace composites at Ohio State University. "Once I realized the advantages--10 times stronger than steel, one-quarter the weight, and especially the lack of corrosion--I started looking into the potentials of composites for bridges," he says.
Still, civil engineers are a cautious lot, so Morton spent three years studying the notion and talking to his counterparts in other states and Washington. "Composites obviously were going to cost a little more, but because the benefits could outweigh the upfront costs, we decided to go for it," he says. Morton then hunted for a major bridge that could serve as a national test bed--and found the deteriorating span on Salem Avenue, which is crossed by 30,000 vehicles a day. Next, he enlisted researchers at the universities of Cincinnati, Kentucky, and Maine, plus Ohio University and the U.S. Army's Cold Regions Research Lab in Hanover, N.H., to help develop tests that could be used by bridge builders anywhere in the U.S. That cost $800,000.
Installing the composites roadway cost $7.1 million, but that includes an elaborate monitoring system that will keep a constant vigil over the bridge. There are 180 sensors buried in the road connected to a computer and the Internet, so researchers at the universities can check remotely on how the four competing materials are holding up.`HUGE.' ODOT's Morton is optimistic that composites will become a common material for bridges, including "steel" support beams. And while Brunswick Technologies' White Steel isn't the only horse in the race, Grimnes is confident he has found a profitable niche. "White Steel is only about 10% of our business now"--last year, BTI's total sales were almost $45 million--but Grimnes predicts that "infrastructure is going to be huge."
Beyond buses, there's Detroit. That's the next target--especially the booming market for pickup trucks. "Composite materials would be ideal for the truckbeds on pickups," says Grimnes. In a few years, he predicts, the world's car makers will be using an average of 100 pounds of composites in every vehicle they build--a total of 4 billion pounds. If BTI does as well in Detroit as it's doing in bridges and buses, Grimnes will need a couple of those pickups to haul the cash to the bank.By Otis Port in New YorkReturn to top