Whenever gases or liquids are introduced into a vessel under pressure, the supply pressure must be greater than the pressure in the vessel to prevent reverse flow back into the supply system. Protection against reverse flow can be obtained by installing a check valve in the supply line. With a check valve in the line, the valve will snap shut if the supply pressure is too low, or if the pressure in the vessel should rise above the supply pressure. This protection is particularly important on stirred reactors where gas enters through a dip tube. With liquids in the vessel, any back pressure will force liquid back into the gas tank or into the gas supply system. Parr stocks the poppet check valves listed below for incorporation into the user’s supply lines. These valves have a 10 psi normal cracking pressure and are rated for 3000 psi maximum working pressures. Check valves with other specifications can be furnished on special order.
| Poppet Check Valves|
|363VBAD||Stainless||1/4″ NPT (F)|