| 摘要 |
<p>1436092 Valves MISUZU MACHINERIES & ENG Ltd 21 Jan 1974 [24 Jan 1973] 02817/74 Heading F2V [Also in Division F4] A flue gas valve installed in a pipe between a gas generator and a scrubber comprises main and auxiliary valve discs 3, 5 mounted on a spindle 2 rotatably mounted in the pipe 1, the main valve disc 3 serving to close the pipe by engaging valve seat 1<SP>1</SP>, the auxiliary valve disc 5 forming a gap S<SP>1</SP> with the pipe 1, and a sealing air pocket S being formed between the discs 3, 5. Disc 5 faces towards the gas generator and the pressure in air pocket S is made greater than the flue gas pressure so that flue gas cannot get into space S. Thus any leakage past disc 3 is only of fresh air with no corrosive properties. The space S is provided with pressured air via pipe 6 and port 1a from the boiler draft fan.</p> |
