A 30-YEAR-OLD multicompartment chemical trailer moving at low speed suddenly breaks in half. Fortunately, no product spills from the fully loaded trailer, no injuries result, and no major highway closings are needed.
Was it an isolated incident or is it an indication that the oldest tank trailers in the US fleet should be consigned to the scrap heap? How old is too old?
Issues related to the aging of the US tank trailer fleet were discussed in some depth by Jack Rademacher, Brenner Trailer Inc, and Jim Jungels, Polar Tank Trailer Inc, during the 2002 Cargo Tank Maintenance Seminar November 4-6 in Chicago, Illinois. The annual conference is sponsored by the National Tank Truck Carriers.
Rademacher stressed that tank trailers are not designed for infinite life. Even though manufacturers turn out well-built products and many fleets do an excellent job of maintaining them, the tanks will wear out over time.
He added that the Department of Transportation has expressed concern about older multicompartment stainless steel tank trailers that are still in operation. “No inspections or tests of the connecting structure are required at this time, but TTMA (Truck Trailer Manufacturers Association) has been asked for an inspection recommendation,” he said.
In all likelihood, inspection requirements for multicompartment stainless steel tank trailers would include the following: A hydrostatic test of the connecting structure to five psig and a visual inspection for corrosion and cracked welds.
“We don't think five psig will reverse any bulkheads,” Rademacher said. “The void area will have to hold the test pressure for 30 minutes. Any structure that fails would have to be repaired before the trailer can be returned to service.”
Jungels provided a broader perspective on the aging US tank trailer fleet. The average age of tank trailers in 2001 was 11.45 years, with 16% in excess of 20 years. Dry bulkers average 10.64 years, and 14% are more than 20 years old.
“Put simply, we have too many old trailers on the road,” he said. “It is worrisome that so many tank trailers are more than 20 years old. Tank truck carriers need to renew their fleets. Somehow something has to be done to enable carriers to make more money and justify fleet replacement.”
Jungels listed several reasons for the large number of older tank trailers that are on the road. Poor profitability among tank fleet operators is a leading reason. Rates are too low.
“Improved profitability is the only thing that will enable companies to renew their tank trailer fleets on a large scale,” he said. “Fleets buy new equipment right now primarily to handle new business.”
Fleet consolidation is another factor that has kept older equipment on the road. “We have too many used tank trailers out there, and carrier consolidation is a big culprit,” Jungels said.
Largely because of these factors, demand for new tank trailers is at an all-time low. That's bad for the industry, because it is squeezing tank manufacturers to the breaking point, according to Jungels.
He recounted that 12,000 new tank trailers were produced in 1979, and the total had dropped to 4,800 by 1983, three years after trucking industry deregulation. In the decades since deregulation, at least six manufacturers have gone out of business, and many more plants have been shuttered.
“Tank builders are in survival mode,” Jungels said. “We've been in a 21½2-year depression with short backlogs and lead times. We're hit by the high cost of government regulations and for the materials we use in building tank trailers.”
Major changes are needed to ensure survival of the cargo tank manufacturing sector and to guarantee that the tank truck industry continues to operate safely and efficiently. Jungels proposed five industrywide initiatives.
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Carrier profitability must be improved. Rates must be raised enough to cover fleet renewal.
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Older inefficient tank trailers need to be taken out of service and scrapped.
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Manufacturers must look for new ways to reduce trailer tare weight and boost payload capacity.
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Higher gross weights also would be part of the strategy for higher payloads, and fleets and government regulators need to consider alternatives such as B-trains.
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Standardized weights are needed for every part of the Unites States, Canada, and Mexico.
“These changes would benefit everyone in North America, not just US tank trailer builders,” Jungels said. “We need to meet the challenges of traffic congestion — which has become a serious problem in many urban areas — by maximizing vehicle capacity to reduce the total number of trucks needed. We need to live up to our obligations under NAFTA (North American Free Trade Agreement). All of this means we need to take a fresh look at the equipment used to transport liquid and dry bulk cargoes.”