Building a Shaker for Fatigue Testing of Electrical Components

[reprobaindoles]

This is probably a very simple question to a vibration expert, but I haven't worked with this in many years...

I have been asked to build a shaker for a product we make for fatigue testing of internal (electrical) components. We basically have a budget for buying a couple shakers off the shelf and welding a frame of some sorts. The product is Ø1.875" x ~9'L (tube shape) and weighs a total of about 68 lbs. The target vibration level is 5-10G shock.

I want to buy a shaker from McMaster (maybe several) and build a bracket to connect it to the tool. The shakers are qualified by force in lbs and vibrations per minute. How do you size the shaker and how heavy does the mounting block need to be to get 5-10G vibration onto the tool? what about noise? how would you mount the setup in the shop?

The goal is to catch any poorly soldered connections, broken wires, loose parts, etc. before shipping it out. Do you have any other recommendations for a shaker for this purpose?

 

[GregLocock]

10g on a 68 lb mass, that is a fair old requirement, just under 1000 lbf.

have a look at this graph for example,

http://www.tirakorea.com/2006/pdf/system_tv_5550_ls.pdf

I'd guess that is 20000 dollars


Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[jimkinney]

Don't forget the mass of the support frame in the force calculation, it usually weighs more than the DUT. Also, trying to control multiple shakers (if that's what you meant by several McMasters) for shock testing may be nearly impossible.

Jim Kinney
Kennedy Space Center, FL

 

[MikeHalloran]

We put a bin shaker on a steel table under our complicated electromechanical assembly years ago for a penurious vibration test.

You will want a variable speed vibrator so you can ramp up the G level.

It's noisy, but the test won't take long. Pieces of our stuff started falling off within 30 seconds, before we had even ramped up to max speed.

That's when we started using Loctite on _everything_.



Mike Halloran
Pembroke Pines, FL, USA