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The only place for a coil spring is up Zebedee's arse
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Is there such a thing as a bench test for an air bag? I have an old air bag that i want to test... short of fitting it to one of my fleet is there a way to do a leak test on one? Obviously a bike inner tube you can just hang up on a hook and see if it goes down...not sure how that translates to an air bag though... This may turn into a comedy thread of course...let's see

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Do you mean you want to blow it? It won’t be useable after that. We need to test the escape slides from time to time on the Boeings I work on. It then needs to be sent for overhaul.

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You'd need to rig up something to stop it blowing the ends off but it will have to be pretty strong and hold it securely. To properly test you'd need to inflate to around 75-80psi as that is what it needs to support over a half tonne (1/4 of the weight of the car).

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Oh! SUSPENSION air bag, got it!

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Good point, suspension air bag or air bag? Air bag is easy, connect two (long) wires, get a safe distance away and connect to a battery. If it does nothing, it's buggered, if it does something it wasn't buggered but is now......

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Yes, I was thinking SRS Airbags.

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Lol. Airbag as in spring... So I guess I cd mount it in a trolley jack, but I guess i'll just try it on the car.
Wd be fun to test a few SRS air bags though :-)

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If you've got a press you could mount it in that but you'd need to make sure it was held flat at top and bottom so it wouldn't launch itself out at you.

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or make a sturdy frame of similar dimensions to the airbag mounts in the car.

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Sheesh guys there are easier ways to commit suicide!

Ages ago was standing beside the right front corner of the car when the bag just let go all on its ownsome! One heck of a scary bang. Instant levitation and "that close" to needing clean pants.

Out of curiosity I did the maths as to how much energy was involved and how dangerous those things are if they let go in the open. Sobering, getting close to hand grenade without the shrapnel. Not quite as bad as an over-pressured tyre letting go, which has been known to kill, but absolutely not something to do for fun.

I guess dumping it in the lake, or big water tank, like the scuba folks do might bring the risks down.

Back in the day the firm wanted me to use 4,000 psi air and nitrogen so I got to sit through the safety videos.

Clive

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Lol...I'll leave well alone then...I was just curious

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After all the warnings and thoughts of what could go wrong, it's almost worth doing it to see what can happen......

For leak testing AC systems I've got a bottle full of Nitrogen at 190 bar, using that could get interesting. From a safe distance anyway.

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The safest way to test it is to do what we do with SCUBA tanks and boilers, and hydraulic it. Completely filled with water, no air at all. Then you add a little more water under pressure until the desired test pressure is reached (in our case about 5,000 PSI for a SCUBA tank). In the case of a SCUBA tank, you only need a few ml of water over completely full to shoot the pressure from 0 - 5,000. In the case of an airbag, which can stretch, you will need more than that. The advantage is, if it lets go, there is a spray of water, that's it. Do it on the bench in front of you. The worst that will happen it you get wet if there is a catastrophic failure.

Drying it out inside after, well I'll leave that to you .....

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A few years ago my P38 was intermittently running roughly. It would suddenly lose almost all power then need to be revved up for a minute or two before it would recover. On this occasion I managed to pull into a lay-by & as I was revving up the engine trying get it to deliver some power there was an almighty bang from the rear. To add insult to injury not only had the CPS finally died but the near side rear air spring had exploded.