Gone quiet on Sarj?

Have there been any significant discoveries about the reasons for the
failure of the hardened layer as yet?

Brian

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From the program overview briefing Monday:
They believe the cause of the starboard SARJ damage is lack of
lubrication from the premature wear of gold impregnated in the rollers
of
the trundle bearings (the gold was the lubrication).. During STS-126
they're going to finish cleaning the race ring & replace all the
trundle
bearing assemblies on the starboard SARJ, and lubricate the 3 bearing
surfaces of both SARJs' active race rings with something called High
Vacuum Brakeo grease. They believe this will reduce the vibrations
enough
to use the starboard SARJ the way they have been recently (move it a
little to optimize solar angle & leave it for awhile) & up to 60 days
at a
time of nominal rotation if / as needed, til assembly complete.

They also mentioned an interesting plan they're working on for the
UF-5
mission / assembly complete time frame to fix the SARJ while
retaining
the inboard race ring as backup.. It will involve increasing the gap
between the 2 race rings by 10-12 inches and bolting a new race ring
to
the front of the damaged one. It will take as many as 10 EVAs to
complete.

Hmm, well I missed that, but I did wonder about doing something similar,
but the clearances are a bit difficult as far as I can see. So, are they
going to lubricate the other bearing as well, just in case? Seems odd to me
that one is basically shedding bits while the other only has a fine
dusting after all this time. I begin to wonder if they did enough
temperature cycling on the bearings during tests.

Brian

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...
From the program overview briefing Monday:
They believe the cause of the starboard SARJ damage is lack of
lubrication from the premature wear of gold impregnated in the rollers
of
the trundle bearings (the gold was the lubrication).. During STS-126
they're going to finish cleaning the race ring & replace all the
trundle
bearing assemblies on the starboard SARJ, and lubricate the 3 bearing
surfaces of both SARJs' active race rings with something called High
Vacuum Brakeo grease. They believe this will reduce the vibrations
enough
to use the starboard SARJ the way they have been recently (move it a
little to optimize solar angle & leave it for awhile) & up to 60 days
at a
time of nominal rotation if / as needed, til assembly complete.

They also mentioned an interesting plan they're working on for the
UF-5
mission / assembly complete time frame to fix the SARJ while
retaining
the inboard race ring as backup.. It will involve increasing the gap
between the 2 race rings by 10-12 inches and bolting a new race ring
to
the front of the damaged one. It will take as many as 10 EVAs to
complete.