Failure Root Cause Analysis and Remediation
Work Examples
For a major waste-to-energy facility in NY, Expert Evaluations replaced the OEM and found the root cause of 6, last stage blade failures (and replacements) over the past 30 years.
For a major United States Naval facility, Expert Evaluations found that the supposed governor issue was actually a valve problem.
For a large Georgia based papermaker, Expert Evaluations oversaw the disassembly, remanufacture and relocation of a GE turbine generator unit without assistance from the OEM.
For a bio-mass client, Expert Evaluations worked in conjunction with Dresser-Rand in providing the logistics to relocate a T/G system.
For an oil refinery in Bulgaria, Expert Evaluations found the root cause of the periodic mechanical drive turbines overspeed to be shaft currents saturating the speed pick up signal.
For a major nuclear equipment manufacturing company, Expert Evaluations found a failure mechanism in their RCP thrust bearing.
For the largest electric utility in the world, Expert Evaluations found the root cause of a generator failure as a surface tracking corona via nitrite acid attack of the aluminum cooler fins. This chemical reaction was arrested by eliminating water vapor in the TEWC generator.
As a Fire Protection Engineer, Expert Evaluations designed several turbine generator protection systems shutting off turbine oil following coast down (two successfully battle tested).
As EPRI, Expert Evaluations has successfully argued the merits to reduce the over-speed set point to 2-3% from 10%.
For a vertical hydro unit owner, their coupling between generator and turbine was essentially held together by a snap ring with -1 x ½” rectangular grove on both shafts. The sharp corners were stress risers and the generator shaft broke (fatigue failure) dropping the blade rings into the trail race. The OEM’s only recommendation was to supply a new field. We recommend and managed a field repair consisting of a new snap ring groove in the remaining shaft and spacer piece between the coupling halves. The unit has over 20 years on this repair.