FURNACE PRESSURE CONTROLLING SYSTEM OF BOILER

摘要

PURPOSE:To effectively suppress furnace pressure rise by proper control of opening of an induced draft fan (IDF) inlet damper and the IDF revolution when a few IDF are tripped in a boiler equipped with several IDF. CONSTITUTION:A balanced type boiler is provided with forced draft fans (FDF) 1 and hydraulic coupling driven type IDF6. A preceding control signal is inputted to a vane driving device 24D of an IDF inlet damper 24 through a function generator 29 depending on the opening of an FDF inlet damper 23. A driving signal is given to a hydraulic coupling scoop tube driving device 41 through a function generator 34 depending on the opening of the damper 23. Function generators 43 and 36 are provided with the above function generators 29 and 34 in parallel. Driving devices 24D and 41 are controlled depending on outputs of the function generators 43 and 36 when a few IDF6 are tripped.