1/4" Plastic Normally Open Solenoid Valve

This is a little different to many of the valves discussed here, but I am sure someone has had experience with these.I require a 1/4" BSP female plastic solenoid valve. It needs to be 12vDC, and to have minimal exposed metal (preferably none as the marine environment will kill it quickly). The challenging part is it must be NORMALLY OPEN. It must also be cheap (<8USD - purchasing 200 PA).It is vital to be normally open as if power is removed, there is a risk of sinking the vessel.I have spent a large amount of time on google searching for these to minimal success. I have found a single valve that is adequate (R.P.E srl, Italy), but the price is a little high.The most common applications for these is irrigation, coffee machines, home appliances etc, but a lot of these are not designed for exposed operation.The design is for a vent to atmosphere to break a syphon on a marine vessel.Medium is atmospheric air, but must handle salt-laden air, salt spray, and salt water, and associated buildup with this type of environment.Pressure is -10psi to 300psi (valve must withstand not operate). Operation is at ambient pressure.Flowrate is <10 lpm.I am not interested in metal valves (even though they are capable of doing the job), as we are a plastic fitting manufacturer extolling the virtues of non-metallic fittings. It would be unwise from a marketing point of view to say 'but in same cases it is ok'.I am happy with regards to meeting certification requirements, and take UL as a nice to have but not required. DNV/Lloyds certification is not required.

From the original1checkvalve
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