A number of months ago I recall seeing several articles about problems with failures in the ES44 turbochargers. Sounded like a supplier had delivered a sub-standard part. Haven’t seen anything lately. Does anyone know if the problem has been resolved or is still continuing? Was the failure limited to AC or to DC, or did it affect both? Thanks. Roger Thomas
AC drive and DC drive Evolution series use the exact same diesel prime mover so the turbo issue affects them all…the differences in the 2 types are all in the electrical traction system …
problem fixed
Yes it seems that they have been able to lay this one in the lap of the vendor. The part as furnished should have been inspected and probably conformed to dimensional tolerances in every way. I don’t know how they could test the material for conformance non destructively. I would have thought that they would have inspected the vendors facilities to see if they could make the piece in the first place. The type of failure has been kept a military secret. My guess is that this turbo having a very high pressure ratio would have the shaft very highly stressed in torsion at the maximum speed and a weak shaft would have twisted off between the compressor bearing and the turbine wheel. Where the pieces coming through the side of the locomotive would be from the unsupported turbine wheel shoved off center and taking off through the turbo housing. Reducing engine power reduces the volume of exhaust resulting in reducing the turbo speed and lowering the torque in the shaft pumping air at a lower speed. I wonder what the factor of safety is in this design.
Working on trucks and mining equipment for 30+ years I have seen my share of turbo failures. Some are spectacular when it comes to the destruction they leave. Most of the failures are on the compressor side. When the compressor wheel explodes it sometimes takes the housing too. I have seen some explode off the exhaust manifold. Then there is the labor intensive clean up of metal fragments and steaming the oil out of the after coolers. The newer twin turbo engines always takes both turbos out at the same time when one fails they both go. The last turbo job the turbine wheel was missing completely and the exhaust was full of oil but the compressor side was fine.
Pete
well they are technically “fixed”; however On the UP at least we are still not allowed out of the cab when the units are under load, either on the road or while being load boxed. that tells me they really aren’t too sure of the fix. (The ONLY unit to every have this, we are designing some armor plating to put inside the carbody doors to protect against turbo failure on these units.) The main majestic failure mode of these turbos was a torsional failure of the shaft it would let go on the turbine end and ka boom!! a well ventilated toaster!