I. Overview smoke isolated gate according to the relevant departments of the power of product design standards, the production flapper door. Huaneng products can be long-term safe and reliable operation of the system. Air preheater flue gas inlet and outlet isolation valve to be set in the flue gas duct systems, in order to stop the commissioning phase of the device to prevent flue gas into the air preheater. Second, smoke isolated gate has the following features: 1. Using single flapper mechanical seal, which can effectively cut off the hot flue gas. 2. The flapper travel agency has cleaning function, open, not shut Jamming. 3. flapper opening and closing process left ring, extend seal life. When the flapper door is closed, you can effectively block the hot air through. Flapper door is not deformed, switch flexible, accurate, no leakage, no leakage. 4. Huaneng isolated door sealing surfaces composed of a single layer of the bezel, flexible graphite seals are used between the card and the package of stainless steel housing. 5. flapper sealing surface after finishing, in order to ensure tight seal. Design of the sealing surface to avoid direct erosion hot ash, the ring can be a long time without damage. 6. Huaneng produce single card isolated heat-resistant steel doors, in order to ensure a rigid flapper, flapper be reinforced in order to ensure rigidity, to ensure isolation of the door at the maximum pressure, maximum temperature and is capable of operating close close , does not bend or JAM. After isolation the door closed, locking means flapper locked in closed position, in order to prevent wear of hot ash locking device, concealed locking structure. Third, smoke isolated door performance parameters: 1, for flue gas temperature 300 ~ 550 ℃, apply pressure 1 ~ 15KPa; 2, cold state (temperature 0 ~ 40 ℃), apply pressure 0 ~ 30Kpa 3, smoke isolated door seal effect of 100% isolated, no leakage. 4. Operation: electric, pneumatic and manual. 5, each cut off after the door assembly in the factory to make sure that the overall performance of tests to ensure the flapper door opening and closing flexible, sealed tight, the overall performance to meet: A, flapper door switch operation flexible, non-JAM; B ,. flapper opening and closing and locking the mating accurate, reliable, indicating correct; C ,. each shaft seal tight, no leakage; D, space and size and other ministries in line with the demand side.