| 摘要 |
<p>The safety equipment maintains a vacuum inside a vessel into which there extends a pipe for gas under pressure. An automatically-operated valve is fitted in the pipe outside the vessel, and a receiver is connected to the pipe between this valve and the vessel. A valve control pipe is connected to the receiver, so that when pressure in the latter falls below a predetermined value in the valve shuts. A manually-operated control valve can be connected in parallel with the first valve, and there can be a throttle valve in series with the latter. The first valve can be pneumatically-operated, and connected via a control pipe directly to the receiver.</p> |
