摘要 |
<p>An air seal valve (8) is formed from an annular valve body (20) having a circular valve plate (12) disposed internally thereof with a pair of axially spaced valves (34 and 50) thereon defining a fresh air plenum (28), wherein one of the valves (50) includes a truncated conical plate having a radially outer edge (54) engageable with the valve body (20) to effect a seal thereagainst. Clean air under pressure greater than the pressure of contaminated emissions flowing into the valve is conducted by a manifold (26) to an outer plenum (22). The clean air flows from the plenum (22) through a plurality of apertures (30) in the valve body (20) to the inner plenum (28). In the event of an imperfect seal within the valve (8), the clean air flows through the leak path into a conduit (10), ensuring that contaminated emissions do not escape past the valve (8).</p> |