Any prime mover exhibits the effects of wear and tear over time, the problem of predicting the effects of wear and tear on the performance and functionality of a gas turbine is the result of the fine-tuned cooperation of many different components. The gas turbine should be treated as a system rather than as isolated components, treating the machine is this way reveals the overall effects of degradation on the match of the components as well as on the match with the driven equipment.
In general terms the mechanisms that cause engine degradation are changes in blade aerofoil surfaces due to erosion or fouling, the resultinh effect on the blade aerodynamics, changes in seal geometries and clearances, the effect on parasitic flows, changes in the combustion system, shaft and bearing wear resulting loss of shaft control, induced vibration and so on.
Seal geometry which if degraded may lead to some particularly difficult issues such as internal oil leakage, corrupt parasitic flows, risk of lubricant fire, oil escape resulting in mixing with intake air or combustion process causing fouling and resultant loss of CDP and engine performance, .
Modern repair techniques may be applied to both the rotating and stationary elements of the labyrinth seal components concerned in order to recover geometry and seal function. Similar repair recovery techniques may also be applied to the dimensionally high toleranced, complex and costly seal finned rotor shaft components and their corresponding bearing journals that may have suffered degradation over time through wear, pitting, fretting, chemical contamination or foreign particals in lubricant, corrosion or engine failure.
Purchasing new replacement Shafts and Seal components to recover bearing control and seal dimension and function is an expensive route, there are alternatives!
Contact us to discuss your potential shaft repair requirements in further detail.