| 摘要 |
<p>A system of pipelines and cut off valves for feed of heating oil from a series of non-interconnected storage tanks, has suction and return pipe feeds (5, 6) running to each tank (1, 2). Each feed and return pipe (5,6) is connected to an electromagnetic cut off valve (8, 9) of spring return type, which cuts off in the zero position and twin cut offs. The valve system interlinks the return pipes (6) and burner return pipes. A boundary or limit sensor (13, 14) controls the electromagnetic cut off valves (8,9) such that they may only open when all the other valves are closed.</p> |
