- Low pressure hoses have a general working pressure of around 140 psi; much lower than the pressure contained in the cylinder. The ends are almost as wide as the hose itself to allow gas to flow through it easily.
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| Wide hole of a low pressure hose |
- High pressure hoses have a working pressure that is equal to the compressed gas in the cylinder so a diver can constantly monitor how much compressed gas remains on a dive. There is a very small hole on the end of the hose that connects to the first stage regulator. In case of failure, a stream of gas at 3000 psi will be released, however it will only be in a tiny stream so it will take far longer to deplete the cylinder of all compressed gas.
- To change a rig's high pressure hose that connects the submersible pressure gage (SPG), turn over the console (if applicable) and remove the plastic protector cover from the back of the rubber housing. This will allow you to bend the rubber console and push the gage out of the unit.
- Bend the rubber console while gently pushing on the back of the gage.
- Use two wrenches to loosen the nut, then continue to unscrew the nut to remove the SPG from the hose.
- Back the old hose out of the rubber console.
- Now you will be left with the gage, the "swivel spool" which is the o-ring hardware that allows the gage/console to rotate at the end of the hose, and the high pressure hose itself. The swivel spool will remain in either the SPG or the hose, so use pliers to gently remove the piece. Do not let any dust, hair, etc. to stick to the lubricated piece.
- Feed the new hose through the console, replace the swivel spool in the SPG, then attach the SPG to the end of the high pressure hose and tighten.
- Pull the hose back through the console and fit the gage snugly into place. This may take a few minutes. Do not use too much force or pull too hard on the hose. A bit of wiggling should suffice.
Read more:
http://www.divegearexpress.com/regulators/hoses.shtml
