lexAN IS COOL BUT IT MIGHT EXPLODE IF OVER PRESSURED. TRY PLASTIC GAS PIPE THE ORANGE STUFF, IT ONLY SPLITS DOES NOT EXPLODE. AND PVC WATER PIPE IS A BAD IDEA TOO!!!!
RICK
lexAN IS COOL BUT IT MIGHT EXPLODE IF OVER PRESSURED. TRY PLASTIC GAS PIPE THE ORANGE STUFF, IT ONLY SPLITS DOES NOT EXPLODE. AND PVC WATER PIPE IS A BAD IDEA TOO!!!!
RICK
Someone should start producing these so that people who do not have the time or inclination to build them can purchase for use with our kits.![]()
ok ok, I'm working on it but they will be a little more involved and be expedition quality, i can't go selling stuff that will blow up in ya face![]()
lexan is all very nice apart from it stress fractures and with out warning![]()
i have all componants in, but i'm haveing trouble with one suppier that cant get a simple fcuking order right![]()
kind regards john
Last edited by narked at 90; 23rd October 2006 at 19:22.
you know...life is not about waiting for the storm to pass,Its about learning to dance in the rain..
Supporting Shearwater Research Products in Europe
KISS,Optima,Inspiration,Meg
KJ sent me some pictures of the sensor pressure pot he has built for several people.. If there is enough demand he would consider making them...
I'll post something shortly..
Joe Radomski
CCR Trimix Instructor Trainer
ANDI Instructor Trainer Director #10
All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated.
Here is a pot I built out of an OMS 660 canister and an analyzer flow meter to measure all three cells at once. It hooks directly to the Megalodon head, but could be made to connect to any head with the appropriate connectors. I installed a Shrader valve behind the pressure gauge. Just hold the Shrader valve open and purge until the handsets read 1.0, then release the valve. When the pressure builds to 9, 15, or whatever psi you wish, turn off the flow meter and disconnect the LP inflator hose. It will hold the pressure as long as you need. When you want to depressurize the pot, simply open the flow meter so the pot slowly depressurizes (and you won't bend the cells). I ran this by an engineer friend of mine, and he was fairly confident the canister would safety withstand repeated pressurizing to 15 psi. I had the 660 canister and flow meter laying around, so with the other parts I purchased it cost me $15 from parts available at Grainger and computer supply houses. Cheap and easy. No Rube Goldberg here.
![]()
I'm not sure if I would trust an acrylic test pot and you don't need to see inside the pot while you're testing.
Here's a way of making a solid test pot that should be safe if used correctly.
Use steel, it's cheap and won't easily blow up in your face. I've used a piece of 2" schedule 40 tube with flanges welded on each end. You can buy blind bolt on flanges to close each end. Instead of using a gasket to seal the blind ends, get an "o" ring groove machined into each blind flange so that they will seal easily.
You can drill and tap the blind flanges to take a pressure proof bulkhead connector and gas inlet and exhaust fittings and a pressure relief valve.
Do a hydrostatic-test before using the pot with gas. You can use gas as the pressure source but but fill the pot with water first. For commercial use the test has to be 1.5 times the working pressure and needs to be recorded formally.
As far as testing sensors is concerned, you can easily damage sensors with rapid decompression so beware.
I use a pressure transducer and PC to view and log the data from both the pressure sensor and the cell outputs.
Pressurizing cells with air will quickly achieve high ppo2 values and if you want to do a proper deep dive test you will need to use an inert gas to keep the ppo2 at a reasonable level while still achieving the test pressure you require.
I have tested cells to 40 bar with this type of rig and I have found that pressure can bring on cell failure in some instances.
Go easy with the decompression, treat the cells to the same decompression as you would for yourself and they will be fine.
Is pressure testing of cells worthwhile?
It could be but it has to be done with care otherwise you just break the cells.
It's probably not a DIY thing but something that a dive shop could do and present the customer with printed report for their cells.
I have a narked at 90 mini cell checker for sale if anyone is interested :)
Verzonden vanaf mijn iPhone met Tapatalk