Tanks corroded beyond economic repair don't mean the whole car must be replaced. Here's how Amoco was able to preserve an existing fleet for a limited need.

When the battery or tires wear out on an automobile, few people would buy an entire new car. So, figured Amoco oil executives, why replace entire tank cars in their sulphur fleet when much of each car was still in good condition?

The question was raised when sulphur, a byproduct of Amoco's refining operations, began to take its toll on the tanks of otherwise sound cars used to ship the commodity to customers across the U.S. and Canada. "The affected cars had extensive tank corrosion, well beyond limited areas that could be fixed with a weld-over or insert," says Kirk Warner, Amoco's manager of railcar fleets. "They just weren't economically repairable."

The typical alternatives would be leasing new or existing cars, or buying new ones. None of these options seemed very attractive to Amoco, because the existing cars it owned would have to be scrapped.