| 摘要 |
<p>A non-return device for welding installations, of the kind comprising a movable valve arranged so as to free the passage of gas for the normal supply of the torch from a welding gas generator and, by contrast, to block said passage in the case of a back-pressure resulting from an explosion in the region of the torch burner, the said valve including for this purpose closure means co-operating with a seat under the effect of resilient return means, the valve including second closure means operating inversely to the first in such a manner that the displacement of said valve, under the effect of a sudden fall in pressure downstream of the device and against return means conveniently calibrated to this effect, ensures the automatic cut-off of the flow of gas through the assembly.</p> |
