lesson 17　Boiler Management 轮机英语课件.pptVIP

Lesson 17 Boiler Management General management principles and operating procedures are well known and must always be followed to avoid boiler mishaps(意外事故、损坏). In particular: With many small package boilers, the automatic control sequence usually ensures that the boiler fire is initially ignited[lighted] from a diesel oil supply, and changed over to the usual source when ignition is completed. With good management, to facilitate subsequent starting from cold, the fuel system of large boilers will have been flushed through with diesel oil when the boiler was on light duty immediately prior to being secured. When burning such diesel fuel it is essential for safety that only the correct (small) burner tip(锅炉燃烧器喷油嘴) should be used. It should be kept in mind that if fire does not light, immediately shut off fuel and vent furnace. Complete ignition of fuel in the furnace is essential. The burner flame, the smoke indicator(烟气指示器) and the funnel should be frequently observed. With satisfactory combustion, the flame should appear incandescent(发白热光的) with an orange shade(色度) at the flame tip, and a faint brownish haze(烟雾、薄雾) should show at the funnel. If on first ignition the flame is uncertain, badly shaped and separated from the primary swirler(旋流), momentary opening or closing of air register(调风门)[air regulator] may correct. The pH value of the boiler feed water should be kept between 8 and 9 and the boiler density less than 300 ppm. But, if water samples show a heavy concentration of suspended mater, short blow-downs of 20 seconds duration should be given until the sludge content is seen reduced. The boiler should be blown down when the oil burner is operating, the water level lowered and then restored to prove the functioning of the low water cut-out and the oil burner start-up equipment. The boiler scum valve should also be operated at this time to keep the water level clear from floating scum. Fuel burner components and igniter electrodes should be cleaned