Download 3B1 Chapter 8 Boiler Control Systems Actual Questions & Correct Answers and more Exams Nursing in PDF only on Docsity!
3B1 Chapter 8 Boiler Control Systems
An increase in boiler load will cause the airflow to increase first, and then increase in gas flow will follow. Select one: True False - correct answer True In an airflow/fuel-flow combustion control system, the airflow signal becomes the set point of the __________ controller. Select one: a.Feedwater b.Fuel c.Airflow d.Drum level - correct answer B B1C08Q01 When using the International Society of Automation (ISA) control symbols, what does LRC stand for? Select one: a.Load relay controller b.Level recording controller c.Level recording consistency d.Level reducing communication - correct answer B Which of the following are components of a multi-element control system?Manual/automatic (hand/auto) transfer stationSquare root extractorDigital conditionerLow select signal relaySignal couplerHigh select signal relayLocal controllerMaster pressure controller Select one: a.1, 3, 4, 7, 8 b.1, 2, 3, 4, 5
c.2, 3, 6, 7, 8 d.1, 2, 4, 6, 8 e.3, 4, 5, 6, 8 - correct answer D B1C08Q11 As per the definitions in ASME CSD-1, which category is NOT a boiler pilot category. Select one: a.Intermittent b.Continuous c.Steady d.Interrupted - correct answer C B1C08Q07 In terms of an airflow/fuel-flow combustion control system, the adjustment to fuel flow is calculated from the __________ using the ratio relay. Select one: a.Steam pressure b.Feedwater flow c.Steam temperature d.Airflow - correct answer D At low loads, when the steam temperature drops, the tilting burners are tilted _________. Select one: a.Downwards b.Upwards c.Tangents d.Sideways - correct answer B At high loads, when the steam temperature tends to go above the desired value, the tilting burners are tilted ___________. Select one:
B1C08Q13 Which of the following is NOT a typical example of a programming control in a flame safeguard system? Select one: a.Low-fire start positioning b.Steam temperature cross-limiting c.Pre-purge with maximum airflow d.Timed pilot trial for ignition - correct answer B The ______ used in the spray desuperheater must be of the highest quality since any solids carried over will cause deposits in superheater tubes and on turbine blades. Select one: a.Steam b.Metal c.Water d.Internals - correct answer C In a fuel-flow/airflow combustion control system, the fuel flow signal makes the final adjustment to the ________. Select one: a.Feedwater b.Fuel c.Airflow d.Drum level - correct answer B Which of the following is not a type of surface attemperator? Select one: a.The condenser type b.The shell type c.The drum type d.Crossflow type - correct answer D
There are two types of attemperators used: Select one: a.Spray type and surface type b.Surface type and crossflow type c.Surface type and direct contact type d.Crossflow type and spray type - correct answer C An oxygen analyzer can also be provided to indicate the excess oxygen in the flue gas, which assists the operator in controlling the excess air and increasing boiler _______. Select one: a.Load b.Firing c.Tempeature d.Efficiency - correct answer D The gas bypass method involves the separation of the convection section of the boiler into two, or more, _________ gas paths. Select one: a.Reverse b.Crossing c.Parallel d.Counter - correct answer C A sudden increase in load, a decrease in drum pressure, and an immediate increase in heat release, is called ______. Select one: a.Rate b.Swell c.Shrinkage
