Patent ID: 7226010

Claim:
In combination: a roll-bowl type mill for pulverizing solid fuels for use in firing a steam generator, said pulverizing mill comprising: a) a bowl having a predetermined diameter; b) one or more rollers each connected to an assembly through an associated roller bearing, said assembly for holding each of said one or more rollers and for applying a preload on each of said one or more rollers, each of said one or more rollers located a predetermined distance above said bowl; and c) one or more linear transducers mounted on said assembly to measure displacement of said assembly when said mill is operating; and a data acquisition system having as an input said displacement of said assembly measured by said one or more linear transducers, said data acquisition system comprising: a computing device, operable to perform data collection and frequency power spectrum analysis of said displacement of said assembly to determine: a) the diameter, D, of each of said one or more rollers by using a formula: D = F b F r ⁢ D b b) where, F b is a frequency of said bowl and F, is a frequency of determined by power spectrum analysis respectively, and D b is said predetermined diameter of said bowl.