Repeated Catastrophic Mechanical Failures of 62 Ton/Hr Coal Pulverizers

Repeated incidences of catastrophic mechanical failures of 62 ton/hr coal pulverizers in an 1800 mega-watt power plant, will be presented. Background of these failures also includes complete destruction of wheels and hubs as well as a history of poor lubricating oil samples. Consequent damage also occurred to spring frames, pressure frames and grinding table segments.

A fundamental failure analysis approach was developed and performed on the mechanical systems which led to a failure root cause determination and resolution. Some of the fundamentals included witnessing complete major component tear down and reassembly; visual inspection of every component; and observing wheel oil sampling and draining techniques. This presentation will demonstrate a simple approach to resolving a series of major and expensive repeat failures.