| 摘要 |
<p>The invention relates to a cut-off device for a gas pipe, comprising a blade (8) the spread of which is at least equal to the section defined by the seat (9), and an elastic means (8a) for returning the said blade to the so-called open position exhibiting predetermined flexibility characteristics so that the open position of the blade is provided below a certain value of the speed of the gas, which value generates, on the blade, a dynamic pressure which is too low to press the blade against its seat, whereas above this value, the blade is pressed, by the dynamic pressure of the gas, onto the seat and is held in the closed position by the pressure differential between the inside of the upstream pipe and the downstream pipe. <IMAGE></p> |
