[Beowulf] Re: Disks fail at what acceleration? (Jim Lux)

[Jim Lux]

At 08:14 AM 3/23/2006, David Mathog wrote:
>Jim Lux wrote
>
> > At 01:24 PM 3/22/2006, David Mathog wrote:
> > >Anybody know how many g's a typical disk can withstand before it fails?
> >
> >
> > A lot more than 1g...
>
>
> > But, since you want "real numbers"
> > http://www.seagate.com/docs/pdf/datasheet/disc/ds_barracuda7200_9.pdf
> > looks like 63 G shocks over 2msec, operating... 350 G over 1 msec, non-op.
>
>Ok.  So it looks like a bolted rack should be ok so long as it moves
>smoothly with the ground motions.  On the other hand a bunch of
>computers loosely restrained on shelves might or might not
>exceed these limits when they bounce off the shelving sides or the back
>wall.  Ditto for a desktop computer.  These collisions are going to
>be more elastic than inelastic but there is some give in all of the
>materials so the peak Gs even in that case probably won't exceed that
>limit.  Unless of course one falls off the shelf and onto the
>concrete floor...

Depends how much the case deforms.  Falls a meter, case deforms 1 cm, 100G 
shock.