Inspection Detail

Inspection: 309292266 - Southern Illinois Power Cooperative

Inspection Information - Office: Fairview Heights Area Office

Investigation Summary

At approximately 7:30 a.m. on October 31, 2008, Employee #1, #2 and #3 and other employees were manually rotating the 20,800 lb rotor motor assembly during the air heater unit construction at a power generating facility. The rotor motor assembly is a system of modules, containing slow moving rotor that are packed with closely spaced steel sheets. At each end of the rotor, there is a housing divided by partitions to confine the outgoing hot gas (flue gas duct) to one half of the rotor and incoming cool air (combustion air to fire the boiler) to the other. This is the sector plate. As the rotor rotates through the hot gas, each steel sheet (essentially serving as an element) absorbs the heat that would normally exit the stack. As the rotor moves past the outgoing hot gas side into the incoming cool air side, air flows across each heated sheet, and the element releases its heat to the incoming combustion air, thus aiding in heating the air to combustion temperature (approximately 550F - 700F) and increasing boiler efficiency. Rotating the assembly is a routine and necessary step to exercise and lubricate the guide/support bearing structure. Due to weight of the rotor motor assembly and inertia necessary to rotate the structure, Employee #1 and three employees along with a contractor were located on top of the air heater, pushing the rotor motor assembly's modules with their legs and the remaining eight coworkers were located below and beneath the rotor pushing overhead with their arms. mployee #1 and three employees along with a contractor on the top side of the rotor sat on the 4 in. schedule 40 pipe braces/gussets as the rotor motor assembly moved beneath them. Approximately one minute into the rotation, Employee #1 slipped, fell, or was pulled off the 4 in. pipe he was sitting on and fell into the rotating modules. He was carried in a circular direction of travel with them. As the he traveled around the rotor motor housing approximately 25 ft, he became caught in a 3.5 in. +/-.25 in. pinch point where the modules passed under the sector plate and suffered fatal injuries. The cause of death was sudden and massive internal injuries. Employee #2 and #3 were not injured in the accident.

Keywords: WORK RULES, ROTATING PARTS, ROTOR, CAUGHT BY