摘要 |
<p>A liquid dispensing installation includes an air separator, a volume-meter, a main flow valve in a main conduit, and a bypass valve in a conduit which bypasses the main flow valve. The main flow valve and the bypass valve are normally open during liquid dispensing operations, and both valves are closed in response to reduced pressure in the installation or when a given liquid level is reached in the liquid-receiving container. When the valves are closed in response to reduced pressure, both valves or preferably only the bypass valve will reopen when pressure is restored to a given level.</p> |