The GRADE® Program
With over 25 years of servicing steam and gas turbines in the cogeneration and independent power segments, TGM® has developed a service philosophy of providing customers options to support their availability goals while protecting the reliability of their assets: We believe it is imperative to inspect the generator as often as the turbine and turbine auxiliaries. We believe that generator inspections can be performed concurrently with turbine inspections, without impacting schedule. Finally, we believe that with a frequent and structured inspection and maintenance program, costly unplanned generator outages can be largely avoided.
It is with this philosophy that TGM® has developed our GRADE® Program (Generator Reliability Assessment & Diagnostic Evaluation). GRADE® is the leading generator evaluation program in the industry and the only one that provides not just a snapshot of the generator’s condition but recommendations to achieve long term availability through current and future maintenance and upgrades. The GRADE® program is a proprietary algorithm which outputs a letter grade assessment, just like we all received in school. It is a quantifiable condition-based score with respect to the expected service life of the generator.
“A” (3.5-4.0) means outstanding condition:
Generator in new or like-new condition. Recommendations: No work required. Continue to operate and maintain the generator at better than the OEM’s O&M specifications.
“B” (2.5-3.49) means good condition:
Generator is clean, well-operated and maintained. Aging is less than that associated with a generator with comparable hours of operation. Recommendations: Minor cleaning recommended. Continue to operate and maintain the generator at better than the OEM’s O&M specifications.
“C” (1.5-2.49) means average condition:
Generator is moderately contaminated and/or in need of minor rehabilitation (either now or at the next scheduled outage). Suitable for service with the degree of aging discovered generally equivalent to the generator’s hours of operation. Recommendations: Cleaning and/or remedial work recommended. Continue to operate and maintain the generator at better than the OEM’s O&M specifications.
“D” (1.0-1.49) means unsatisfactory condition:
Generator is heavily contaminated and/or in need of significant and immediate rehabilitation. Generator is operational, though the degree of aging discovered is significant. Generator is reaching the end of its current useful life. Recommendations: Significant cleaning and/or rehabilitation work highly recommended. Immediate attention required in order to stop premature aging. Operation at reduced load may be required in order to extend life.
“F” (0.0-0.99) means failing condition:
The generator has either been discovered to have failed in service or during assessment. Generator is inoperable in its current condition. Recommendations: Generator component rebuild required before the unit can be operated.