Power generation plants throughout the world rely on critical process fans for operation. But what happens when a fen rotor, with a wheel rotating at a peripheral speed of 450 miles per hour (mph), breaks? The scene looks something like this: Pieces of the wheel as large as a coffee table can rip away from the rotor, tear through the 3/8-inch-thick scroll of the fan housing and fly 500 feet from the fan. The 12-ton steel shaft—eight inches in diameter at the bearings and 24 inches in diameter at the hub of the fan wheel—can bend and twist like a pretzel. The cast iron bearing housings can break apart. The 4,000-horsepower motor can separate from its heavy concrete pedestal and land on the foundation. The entire plant may be shut down and it likely will take weeks to clean up the mess, completely rebuild the fan housing and install a spare rotor (assuming the plant has a spare rotor on hand).
展开▼
