AN-08 Spring Check Valve/Vent
Check valves, also known as vents or roll over valves, are one of the most important safety and performance features on the fuel cell, allowing air in and out of the fuel cell while keeping fuel contained within the bladder in the event of a rollover. Similar to discriminator valves, check valves use a stainless steel or chrome steel ball to allow air in/out of the tank but blocks fuel when the vehicle turns upside down.
Check valves come in a variety of sizes and styles according to the intended filing application; the larger the vent the faster the tank will fill. Standard check valves are made from aircraft grade aluminum (either 5052, 6061-T6, 6063-T6) and are either welded or bolted to the fill plate directly. "Inline" or external check valves are not suitable for use with fuel cells unless accompanied by another check valve located in the plate.
Bulkhead Style Check Valves
Machined from standard JIC aircraft fittings these vents come in sizes from AN-06 to AN-16. The bulkhead JIC platform allows any JIC style fitting to be attached for routing of the vent line around and out the vehicle.
Similar to a standard bulkhead style check valve these valves incorporate a spring that allows air into the tank but not out. Also known as "one-way" valves, though they must be mounted directly on the tank or fill plate.