【正文】 B. The steam pipe C. The fire side D. The safety valves 1467 A dazzling（ 晃眼睛的 ） white burner flame in the boiler furnace indicates_____. A. proper bustion B. water in the fuel C. excess air D. cold fuel oil Jimei University *1468 In readying an auxiliary watertube boiler for a routine hydrostatic test, which of the following procedures should be undertaken prior to filling the boiler with fresh water? A. The safety valve escape piping should be disconnected from the valve body and a blank inserted. B. The boiler vent valves should be opened. C. All handhole/manhole covers should be tightened up as much as possible to preclude any leaks. D. All of the above. Jimei University 1469 The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if the boiler_____. A. salinity is abnormally high B. steam demand is too high C. water level is abnormally low D. feedwater flow is low 1470 The correct pH value of boiler water is achieved by continuous addition of a suitable_____ to the feed. A. acid B. alkali C. salt D. None of the above. Jimei University 1471 Black smoke ing from a boiler can be caused by_____. A. low water level B. high water level C. excessively high fuel pressure D. low oil temperature 1472 ____ will be used to blow away soot and the bustion products from the tube surfaces. blow down valve B. The scum valve C. The air release cock D. Sootblower Jimei University 1473 After a normal, or safety shutdown, automatic bustion control systems for an auxiliary boiler are designed to prevent the immediate refiring of a burner in order for the_____. A. furnace to be repurged B. electric charge to buildup in the igniter C. fuel pump to restart D. drum level to stabilize Jimei University 1474 Improper maintenance of an automatic auxiliary boiler oil burner could result in _____. A. fuel pump failure B. fan motor failure C. increased feedwater consumption D. decreased boiler efficiency Jimei University 1475 If the fire goes out in an automatically fired auxiliary boiler and the burner continues to supply fuel, there is a potential danger of_____. A. overpressure and dry firing B. a severe furnace explosion C. spalling(破裂 ) damage to the brickwork D. heat damage to the atomizer Jimei University *1476 Prior to lighting off a cold automatically fired auxiliary boiler, yon should_____. A. check and regulate the water level B. close the air cock once fires are lit C. blowdown the gage glass D. crack the steam stop to assure protective steam flow Jimei University *1477 Which of the following items is necessary for all waste heat boiler installations, regardless of design or manufacturer? A. Control of evaporation. B. A separate means to prevent feedwater contamination. C. Power circulating pump. D. Superheater. Jimei University 1478 For proper operation, auxiliary boiler feed water must have which of the following characteristics? A. High oxygen concentration. B. Low pH. C. Proper alkalinity. D. All of the above. Jimei University *1479 When a waste heat boiler is installed in the exhaust of a main propulsion diesel engine, the exhaust gas bypass would be used_____. A. at high loads to prevent overheating B. at low loads to prevent corrosion in the boiler(防止低溫腐蝕 ） C. during periods of high steam demand D. when the turbocharger is in operation Jimei University 1480 When a hydraulic vane pump is working, which of the following is in contact with the vanes? (1) the rotor。 (2) vane。 (2) rotary。 (3) packing。t discharge oil when pumping out _____. A. ballast water B. boiler water C. bilge water D. sewage water Jimei University 1417 A hydraulic machine is one that uses _____ to do work. A. liquid B. steam C. gas D. electricity 1418 In a vacuum distillation system, the case is the higher the pressure, _____. A. the saturation temperature is higher B. the higher the saturation temperature C. the higher is the saturation temperature D. the saturation temperature is more high Jimei University 1419 Because of the reduced_____ in the distillation system, some of the sea water boils as it flows through the tubes of the evaporator. A. pressure B. temperature C. density D. volume *1420 In extreme weather conditions, either hot or cold, control of the air conditioning plant presents_____ difficulties. A. few B. little C. a little D. less Jimei University 1421 Most air conditioning units have____ for adjusting the ratio of recirculated fresh air. Care must be taken not to reduce the fresh air so that stuffiness or smells arise. A. catch plates B. dampers C. regulating valves D. fans *1422 For the intermediate condition, thermostats must be correctly set_____. A. by trial and error反復(fù)試驗(yàn) B. by and large C. automatically D. very easily Jimei University *1423 The cooler as the liquid bees, ___. A. the faster it will evaporate B. the slower it will condense C. the slower it will evaporate D. the faster it will flow 1424 Where an excessive level of contamination is detected an alarm is sounded and diverting valves are operated. The discharging liquid is then passed to_____. A. overboard B. a bilge well C. a slop tank D. a hot well Jimei University 1425 When a boiler is operating, the water level in