Correct size, roundness, concentricity and surface finish of rotor journals are critical to the proper operation of a rotor. Some typical defects that occur in damaged rotor journals include pitting, presence of grooves, presence of hard areas, cracks from overheating, deposit of babbitt from the bearing and uneven wear. These imperfections can impair the proper lubrication of the journal, creating a higher probability of additional journal damage progressing and leading to failure, including a forced outage. In most cases, journals can be repaired by tooling, grinding, honing, and/or super-finishing to close tolerances for improving lubrication and restoring performance. The techniques for repairing rotor journals vary, depending on the size of the journal and the weight of the rotor. Large journals can, in most instances, be refurbished without rotor rotation, and therefore can be done right at site, or in the case of other repairs, at the repair facility. This and other repair techniques will be discussed in this paper. Readily achievable size tolerances and micro-finishes will be discussed, as well as limiting conditions. Photos and experiences from recent rotor journal repairs will be discussed. This paper will be valuable to plant personnel when evaluating the condition of their rotor journals and selecting methods of repair of damaged journals. A discussion of these options, expected improvement, and other issues will add value to the readers ability to make educated decisions regarding journal refurbishment.

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