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$30 million oops

Posted: Thu Jul 26, 2018 3:06 am
by JK
There is just so much wrong here.
A thrust bearing not machined correctly and installed, failure in operation. Damages to the propulsion line to the tune of 30 million. A ship out of service. Legal costs. 25% cost overruns.
It’s a 4 shafter, so they got 3 bearings correct. The ship was accepted from the yard after trials. Any thoughts?


http://gcaptain.com/u-s-navy-seeks-30-m ... ercarrier/

Re: $30 million oops

Posted: Thu Jul 26, 2018 8:46 am
by Merlyn
Just one

OVERCHARGE

MUST BE 22 CARAT SOLID GOLD ( and the housing )

Re: $30 million oops

Posted: Thu Jul 26, 2018 2:36 pm
by JK
:D I assume that they damaged what is forward of the bearing as well.

Re: $30 million oops

Posted: Fri Jul 27, 2018 12:03 am
by Merlyn
What's that then, the engine Room?
Ha!
Bit worried here that the US might be taking our Cock up title away from us concerning our type 45 destroyers ( project Napier ) re their total breakdown in warm waters and having to be towed in ( you had one towed into Canada )
No electric, can't even train the gun or warm the hot chocolate.
New engineering degree in lack of skills/ cock ups to be added methinks.
Anzipods bit disappointing lately though, heard nothing recently.
The other degree in the civil servants world namely bullshitting seems to be on the wane, needs brushing up.
Variants of " oh that, that was meant to happen" and " it's being done when she was being slipped anyway so won't cost any more " wore thin years ago, new ideas re regular failures need addressing pronto.
Perhaps the thrust needs turning over to see if it is stamped with the everyday letters, " made in China" ?
Viewing the whole scenario through my James Bond eyes I am thinking that this could be a far Eastern silent approach to disabling the US task force maybe and I am now thinking about the merits of buying cheap are not so beneficial after all.
What about the other thrusts?
Are they on a time exposure rating too?
What do you think?

Re: $30 million oops

Posted: Sun Jul 29, 2018 3:50 am
by Merlyn
Puzzled as I am concerning the "gear cutting " manufacturing defect on the US Ford Carrier I am struggling to understand how a thrust bearing can in any way shape or form be driven by a train of gears?
This was the official reason given out for the thrust bearing failure.
Apparently GE in Massachusetts cut the gears that failed.
I am thinking that when the word thrust bearing failure is stated we all think immediately of Mitchell Plummer bearings or in this case Kingsbury thrusts.
In neither setups are geartrains employed.
It would appear to me therefore that perhaps the thrust bearing referred to is the one on the reduction box output shaft ,
The one inboard of the coupling.
Any spalling etc of incorrectly meshing gears would, among other places be swept up into the gearbox output bearing ( whether side rollered or more than likely white metalled and cause the problem of the overheat of 92 degrees excess indicated in the control room.
As it's probably a double reduction box fitted this component is one of the most expensive in the ship normally requiring a dry dock operation and a hole cut in the ships side to access same.
And if one is defective how far away are the other three?
Interestingly I see in September 2002 a Machine condition analysis by Azima in the US was conducted on a warship which over a period of time revealed above normal strong series of intermediate shaft rate frequency harmonics in one of the ships reduction gearboxes.
When stripped one of the high speed gears about three feet in diameter revealed a two and a half foot long crack in the web which had not been picked up by the ships vibration gauges etc in the CR and had this continued to be used would have caused a complete breakup of the box.
So bearing in mind the thirty million bucks US quoted repair costs I am guessing here that because of the gear cutting cockups by GE the job entails a dry dock, hole to be cut in the ships side and a new box fitted.
Far more than what one might firstly have thought, merely a shaft thrust white metal failure in the Mitchell/Kingsbury thrust block.
As I am not familiar with US warships engine rooms and the release / admittance of military information by them I think my theories may well be not far off the truth.
So how long is this carrier going to be in drydock?
Anybody further in the know out there?

Re: $30 million oops

Posted: Sun Jul 29, 2018 3:58 am
by JK
Yes that makes better sense. I assumed a Mitchell thrust bearing as well. I expect the gearbox is a very complicated arrangement. Engine/turbine inputs, high low speeds and PTOs. Whatever happened to simple and robust.

Re: $30 million oops

Posted: Sun Jul 29, 2018 6:23 am
by Merlyn
Might be a spanner in the works concerning my brain wave.
She's steam turbine driving alternators.
So hardly any thrust transmitted as apposed to being on shafts.
The herring bone double diag. helical gears ( the bull gears, the two large ones ) will of course knock out thrust transmissions to virtually zero as regards the box output leaving of course the shaft thrust transmission into the box should the Plummer blocks allow it.
Should still have thrusts though to keep the gear trains mesh
in a constant and correct teeth contact etc.
No where near the thrust transmitted versus on shafts though.
However I still can't find a gear train driven thrust blocks so I am sticking to my theory concerning reduction box failure, ( or failures ?)

Re: $30 million oops

Posted: Wed Aug 08, 2018 1:11 am
by Merlyn
Despite much research I am still struggling with the causes of this gear cutting manufacturers defect concerning thrust bearings?
Being interested in this problem source my investigations are not revealing much at all, understandably perhaps as it's a "security " issue together with obviously a cock up job there exists the major embarrassment feature displayed for all the world to see.
I also note in looking many other problems with this carrier, both in firepower, catapults and engineering whereby one of the turbines rotors had to be changed after sea trials.
However I have discovered one major change which apparently no other ship ( whether it be a warship or not ) which has taken place.
This is revolutionary to say the least and for me goes back to starting out my apprenticeship in 1960 .
The best way perhaps to explain this would be by going back to then as a first year apprentice and being taught lots of things by other senior apprentices.
There were many things beside engineering that one had to learn and being " set up " was predominant.
This particular happening was not taking place in the engineroom but at the local Saturday night " hop" ,
i.e. The dancehall.
Us juniors would go along in the hope of associating with the seniors who would gang up at the bar and we would all wait and hope for anything to kick off.
One of the first things I learnt back then was taking place in the company of local girls who all had to be in the earshot of our apprentices for this windup to work.
One apprentice would announce he was off for a " pump out " and would disappear to the local toilet.
Apon his return he would be asked in a loud voice "what's those new toilets like? "
The reply was always the same.
" it's ok but the China's cold "
This was obviously aimed at all the girls to hear and one always envised crowds of girls either stalking or following the apprentice home to see perhaps if indeed what had been stated was actually true.
It never worked but it was always good for drunken sniggers and derogatory remarks to be bandied about whilst propping up the bar.
Now I digress and revert back to this lame carrier.
Any future young crew members applying to join the US navy could never benefit from the " China's cold " syndrome and as such this is yet another major change in the life at sea as it is now.
Sadly no more bragging after pumpouts, that joke/ set ups gone fore ever and cannot ever be enjoyed by any crew member on board this carrier.
Why you may ask?
Well under the very latest US navy designs there is not ONE urinal on board.
Yes, not one anywhere on the ship!
So although I am not getting far with this gearcutting problem in a thrust set up I have learnt something new in the latest marine engineering world that I never knew before.
No more " China's cold jokes any more on new US warships.
Another major loss to the future marine engineer who will never experience the hordes of girls racing after him on his way back to the ship after a night ashore.
Just thought I would impart this valuable information in passing .
Amazing what you can learn even if we never know what geartrains have to do with thrusts but I still reckon it's the thrusts in the boxes for what it's worth.
Hope this valuable information might be of benefit to any who might wish to join up the US navy and consider it all before signing up.

Re: $30 million oops

Posted: Wed Aug 08, 2018 1:16 pm
by Big Pete
No Urinals, maybe the USN is planning for an all Female Crew?

BP

Re: $30 million oops

Posted: Thu Aug 09, 2018 2:48 am
by JK
I’m more amazed Merlyn discovered this crucial bit of construction detail. Maybe USN have aiming issues when they don’t have a fire control computer?

Re: $30 million oops

Posted: Thu Aug 09, 2018 3:28 am
by Merlyn
Maybe the US navy did a survey and as not many folk logged the "China's cold " Syndrome they decided to do away with urinals as there were obviously not enough candidates to satisfy the criteria for this age old marine engineering saying?
( well, over there anyway ) .
Or is this the start of something big?
Girl Power maybe?
And all because of US crew failing to come up to requirements methinks?
So we all have to suffer because of others failing to meet the requirements ?
And I always thought the Americans were big on everything too.
So the next cock up Carrier maybe totally female crew possibly?
Heard a rumour over here of the Mark Two's name.
USS W.C. Crapper.