| 摘要 |
<p>Valve unit for sealing conduits has a power piston held by gravity or by a spring in its at-rest position, with the valve being open. The piston is connected to the closing member of the sealing valve. The space above the piston is connected to the conduit sections in front of and behind the sealing valve, via return valves, and also connected to the space below the piston via an adjustable throttle. A pressure difference monitor reacts, when a certain pressure difference between valve inlet and outlet is exceeded has an associated relief valve for the space below the piston.</p> |
