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ESS Common Practice

ESS Common Practice

ESS Common Practice

(OP)
I've been asked to do a survey of common ESS practices in industry.  Specifically, if electronics manufacturers still use burn-in, or if they have primarily shifted to HASS or some type of temperature cycling.  I really need specifics about what companies are doing.  The types of products I'm interested in  are: cell phones, power supplies, hard drives, etc.  I care about the assembly level, not the component level.  If anyone knows anything or can point me in the right direction, I would be grateful.

Thanks!

RE: ESS Common Practice

FOULBALLS:  The Institute of Environmental Sciences and Technology (www.IEST.org) can provide information on ESS.  I was involved in ESS in 1984 at a major defense electronics supplier.  At that time it was just getting started and consultants were being born, experts were created and lots of people got involved.  It has lost some of its early steam but it is still around.  I think alot of Defense contractors use it because it is in their contracts.  I suspect that a lot less commercial people use it becasue of the non-recurring start up cost and the perception that "We make a good product, and if you do believe us, ask us".

Properly applied ESS can be useful, but it requires careful organization and monitoring as well as feedback to the produciton line.  It is easy to implement ESS and then create a "hidden factory" that repairs teh failed units.

The key to ESS is to develop the vibration/temperature profiles that identify workmanship defects in the product but do not dmaage the product.

Regards
Dave   

RE: ESS Common Practice

(OP)
CESSNA1

Thanks for your response.  I work for the Navy as a consultant for a program in which Lockheed Martin is the prime.  They already have implemented extensive ESS programs for custom electronic boxes.  LM has proposed removing burn-in from their ESS program and instead extending their temperature cycling.  I have been asked to see what other companies do in their ESS programs specifically, for example, do they still use burn-in at all.

I actually think that quite a few electronics manufacturers use ESS programs.  I know that most power supply and certainly hard drive companies have extensive reliability programs to ensure that their field failure rates stay below the levels that they have budgeted for warranty returns and repairs and to ensure that their claimed reliability is up to par with competition.

Anyone who works in the reliability department of a company that make electronic devices could answer this for me probably.

Again, thanks for your response.
Jason

RE: ESS Common Practice

Foulballs,

Just curious, are you evaluating COTS equipment to see if they can stand military spec?  In my experience both for the thermal and vib, commercial companies either test at low levels or not test at all.  You may have to develop your own ESS to screen the commercial stuff.  If LM is already doing there own ESS you should expose the commercial equipment to the same levels as LM so that you know that the commercial equipment is at the same “toughness” level as LM’s own equipment.  If the commercial equipment are failing at LM’s ESS, then you may have to “ruggedtize” the commercial equipment so that you will not have potential failures that may occur out in the field where commercial equipment were not designed for.  I’m sure the war fighter will appreciate reliable equipment that will work in tough situations.


Go Mechanical Engineering
Tobalcane

RE: ESS Common Practice

We do ESS on almost all our products.  HASS and HALT are really intended to stress reliability fails and not workmanship.  While there is clearly a desire to build things correctly all the time; that cannot be guaranteed and ESS is a good way to catch the few mistakes we make.

TTFN



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