Quote:
Originally Posted by JFP in PA
Everyone here has probably read about chain wear pads failing in these engine, so what factor does slowly developing "whip" in the long chains connecting the IMS shaft to the cams play? Again, data is thin and sketchy.
Only someone like Jake, who spends most of his life staring at the internals
|
There is only two things that can horribly go wrong in a high speed or heavy shaft/bearing design really. First is (as you've indicated) the TIR or runout, or both for this matter. Second is rotational torque vibration & noise caused by improper damping (as you've also indicated, the chainS, and which I also personally suspect; critical speeds). Lubrication is also a failure type however in a shaft application rotating >5000RPM the first two are far more subject to cause catastrophic failures way-long before,
lubrication or not.
The good news is the two main issues above are easily detectable using modern vibro acoustic technologies. My advice for the key players in the IMS business would be to develop a tool that is capable of sensing and therefore take actions based on acquired data from healthy and failing engines. Same techniques used in the aerospace and other transport/military industries, whose those actually are 'real-time'. Basically "
staring at the internals" in engineering terms.
You said "
there is little left to analyze". You are getting this wrong, this needs to be carried out before the failure thus 'preventing it'. Its called predictive maintenance AKA "Solution".
Sending ppl out of fear to change their perfectly fine bearings to me sounds a bit primitive given the vast and widely available condition monitoring kits (high end sensors) and training offered commercially these days e.g. Mobius, Siemens, I pass so many others.
Some who aren't familiar with VA technology will tell you a miniature car engine is a noisy environment (LOLOL), by all means, please ignore these twats; the tech is used in both turbofan & turbojet engines and +50 tons machinery motors/shafts (e.g. ships, energy/nuclear facilities, etc).
Time to modernize a tad guys (if you really care about these Porsche cars anyway).
my 0.2