Vibration isolation mounts
Vibration isolation mounts
(OP)
Looking to design a vibration isolation mount for an electrical box on a piece of space hardware. Thinking of a 4 point connection using 3/8 shoulder bolts (NAS1160?) and rubber bushings (buna-n?). Box weight is approx 50 lbs with connection in primary shear. If I'm heading down the right track I need to find the bushings. Any ideas?





RE: Vibration isolation mounts
RE: Vibration isolation mounts
RE: Vibration isolation mounts
You may be too young to remember the Challanger accident. The rubber O-rings on the booster "hardened" in the extreme cold of the January 1986 freeze and the presence of the the LOX tank. Subsequently, the damaged primary and back-up rings at one joint failed to hold pressure when the RH booster ignited... and began leaking hot-gasses immediately: ~77 seconds later the flight was "over".
Elastomer materials "stiffen" when temps fall... and "soften" as temps rise... resulting in highly variable mechanical properties... not-the-least being deformation/load and dampening characteristics... and all the other factors noted by btrueblood.
Have You looked at wire-rope springs/isolators?
Regards, Wil Taylor
RE: Vibration isolation mounts
I worked a space program at a large US defense company and I remember they were extremely paranoid about using Elastomer material for any damping, shock or vib. The reason being they had a satellite that had solar array snubbers that had outgassed which prevented them from being deployed.
Here are a couple of links for Barry Controls. I've used some of their mechanical isolators for electronic equipment.
http://www.barrycontrols.com/
http://www.stopchoc.co.uk/offshore_avms.html
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RE: Vibration isolation mounts
Two Sources for wire-rope isolation devices
Enindine and Aeroflex
http://www.enidine.com/Aerospace/Wiremain.html
http
Ed