Patent ID: 7726169

Claim:
A method of assessing the performance of a steam generator to determine its maintenance status, comprising the steps of: identifying a set of a plurality of different parameters to be measured for performance assessment of the steam generator with at least some of the parameters measured with the steam generator off-line during and outage, wherein the at least some of the parameters measured with the steam generator off-line include at least one of (i) tube scale accumulation on a steam generating side of the steam generator, (ii) degree of tube hole blockage in support plates on the steam generating side of the steam generator, (iii) tube sheet scale collar accumulation on the steam generating side of the steam generator and (iv) steam generator sludge quantity on the steam generating side of the steam generator; establishing criteria for levels of performance for each parameter in the set of parameters; measuring performance of the steam generator on each of these parameters; comparing measured performance for each parameter to the criteria for levels of performance; converting the measured performance for each parameter to a number or letter grade associated with an applicable criteria for a level of performance; calculating a cumulative average number or letter grade from the number or letter grade for each parameter; and utilizing the cumulative average grade and the number or letter grades for at least some of the parameters to assess the performance of the steam generator.