Sealing hydrogen gas is difficult because it is the smallest molecule and can easily leak through small gaps or imperfections in seals. It also requires a high-integrity fluid-handling system component that can withstand the high pressures required for refueling and the vibration that is part of any moving vehicle. Additionally, hydrogen has a low viscosity and high thermal conductivity, which can make it difficult to seal effectively and maintain pressure. Furthermore, hydrogen is also an extremely flammable gas, which requires a specific type of seal that can handle the safety concerns associated with it. Overall, sealing hydrogen gas requires a specialized and high-quality component that can meet all these demands and that is why it is considered a difficult task.
But with Parker's MPI™ line of fittings and valves, it's remarkably easy. The MPI™ connection is a compression type connection suitable for liquids and gases up to 15,000 psi (1034 bar) and temperatures from -423°F to over 1000°F (-253°C to over 538°C). It's designed specifically to move, store, contain, or transport hydrogen while withstanding high pressures and vibration. With only one and a half turns from finger tight position to seal, the two ferrules grip and seal on the tubing to maintain constant pressure, making it a reliable option for hydrogen systems. Additionally, Parker's Needle, Check, and Ball Valve products have been optimized for increased cycle life when used with hydrogen or other small molecular gases and all use the MPI™ compression connections in sizes from ¼” to 1” tube.