单选题Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）Adouble bottom fuel oil tank temperatureBheater supply steam flowCpressure of the fuel supplied to the burnersDattemperator steam flow in the heater discharge circuit
单选题
Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）
A
double bottom fuel oil tank temperature
B
heater supply steam flow
C
pressure of the fuel supplied to the burners
D
attemperator steam flow in the heater discharge circuit
参考解析
解析：
暂无解析
相关考题：
Which of the listed pressure control valves would be used to establish the maximum operating pressure of a hydraulic system?A.Pressure-reducing valveB.Unloading valveC.Counterbalance valveD.Pressure-relief valve
The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by_______.A.large conical springsB.compressed air pressureC.hydraulic pressureD.exhaust gas pressure
A fire pump may be used for other purposes if ______.A.the other services are run off a reducing station with a pressure gageB.one of the required pumps is kept available for use on the fire main system at all timesC.no relief valves are installedD.all of the above conditions are met
Valves on steam-smothering lines to cargo tanks shall be set with ______．A.The master control valve shut and valves to individual cargo tanks shutB.The master control valve open and valves to individual cargo tanks shutC.The master control valve shut and valves to individual cargo tanks openD.All valves open
单选题Which of the listed pressure control valves would be used to establish the maximum operating pressure of a hydraulic system?（）APressure-reducing valveBUnloading valveCCounterbalance valveDPressure-relief valve
单选题On a ship，a fire pump may be used for other purposes if（）.Athe other services are run off a reducing station with a pressure gageBa separate fire pump is available for use on the fire mainCall other services are operated by a manifold near the pumpDAll of the above
单选题The purpose of the safety relief valves installed on an auxiliary boiler is to （）.Arelieve excess fuel oil pressure during the “off” fire cycleBadmit water to the dry pipeCthrottle the forced draft fan output for proper combustionDreduce excess steam pressure in the boiler
单选题A more sophisticated pressure reducing valve incorporates a pilot valve which controls the fluid above the valve operating piston in response to downstream pressureThe bold and italic word “which” means （）.Aa pressure reducing valveBa pilot valveCan operating pistonDdownstream pressure
单选题Which of the following methods is used to prevent throttling of compressed air through the diesel engine air starting valves?（）AHolding the valve open for a long periodBIncreasing the starting air pressure usedCOpening the stating air valve quicklyDReducing the starting air valve size
单选题Which method should be used to warm up the pump turbines prior to discharge（）.ALock the turbine rotor and slowly bleed in steam until operating temperature is reachedBRun the pump at high speed with the discharge valves closedCRun the turbine at slow speed with the pump disconnectedDShut the discharge valve and run the pump at slow speed
单选题In setting the valves on a steam-smothering system on a tank vessel，the master control valve to cargo tanks should be（）.Aopen and individual tank valves openBopen and the individual tank valves closedCclosed and the individual tank valves closedDclosed and the individual tank valves open
单选题A fire pump may be used for other purposes if（）.Athe other services are run off a reducing station with a pressure gageBone of the required pumps is kept available for use on the fire main system at all timesCno relief valves are installedDall of the above conditions are met
单选题Which one is not the normal operation for boiler shutdown?（）ACarry out soot blowing if permissibleBChange fuel supply to diesel oilCClose steam stop valves on boiler when pressure is reducedDDrain boiler empty when it has cooled down
单选题Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）Adouble bottom fuel oil tank temperatureBheater supply steam flowCpressure of the fuel supplied to the burnersDattemperator steam flow in the heater discharge circuit
单选题Seamless mild steel is used for steam (also copper for moderate pressure and temperature), h-pair, feed discharge and all oil fuel pressure pipingsAccording to the above sentence, which of the following statements is not true?（）ABoth seamless mild steel and copper may be used for middle pressure steamBhpair means high pressure airCThe feed piping of the boilers can be made of seamless mild steelDAll oil pipings are made of mild steel
单选题Differential needle valves used in fuel injectors are directly closed by（）Acam actionBspring forceCfuel oil pressureDfiring pressure
单选题The boiler feed pump discharge pressure is higher than the steam drum pressure to （）.Aensure feed water flow into the boilerBkeep the steam drum pressure highCprevent water hammer in the feed lineDhelp the feed water flash to steam
单选题The water level in a steaming auxiliary boiler will always （）Arise when the steam pressure is increasedBremain constant as long as the feed pump operatesCfall when the steam pressure is decreasedDvary as the steam demand changes
单选题Compensated flow control or constant flow valves are used in hydraulic systems to（）Acompensate for major leaks in the systemBmaintain the original fluid viscosityCallow for changes in pressure and temperature within the systemDassure constant fluid temperature
单选题The thermostatic valve has a throttling action, that is to say the valve can（）Astop the refrigerant from flowingBforce the refrigerant to flowCcause the refrigerant pressure to riseDcause the refrigerant pressure to fall
单选题The lifting pressure of （） is set in the presence of a Surveyor it is locked and cannot be changed.Afuel valves of main engineBinjector pump of main engineCsafety valves of marine boilerDsafety valves of a reciprocating pump
单选题Thermostatic expansion valves can be adjusted for （）.Asuction pressure onlyBhead pressure onlyCsuperheat onlyDsuction pressure and box temperature
单选题In a refrigeration system, which of the following statements describes the actions occurring when a solenoid valves, used in conjunction with an unloader head is energized?（）AThe solenoid valves directs high pressure gas to the valve lifting device raising the suction valve off its seat and causing one specific cylinder to become unloadedBThe solenoid valves directs high pressure gas to the underside of the unloading piston, causing it to rise and allowing the recirculating ports to be openedCWhen the solenoid valve becomes energized, the valve ports become closed, allowing discharge pressure to build up above the piston, shifting it and causing it to unloadDThe solenoid valve allows the refrigerant to pass from the suction chamber to the top of the unloader piston, causing the piston to lift and unload the cylinder
单选题Soot blowers should be used in proper sequence so that（）Aexcess stresses will not be set up in the boilerBthe decks will not be covered with sootCthe soot will be swept toward the uptakesDthere will not be a loss of steam pressure
单选题Which of the following precautions must be taken if an electric immersion heater is used to keep the coolant in a diesel engine warm during the time the engine is secured?（）AThe coolant temperature must be maintained at 180℃BThe thermostatic bypass valves must be manually opened before the engine is startedCThe pressure cap must be removed while the engine is securedDElectrical power to the heater must be secured before the cooling system is drained
单选题The steam coils in a high pressure evaporator used for saltwater service should be de-scaled with （）.Aa needle gunBsoap and waterCa wire brushDa chipping hammer
单选题Excessively low air pressure occurring in the intercooler of a reciprocating air compressor is caused by（）.Aleaky discharge valves on the LP cylinderBleaky discharge valves on the HP cylinderCinsufficient intercooler coolingDlow ambient air pressure
单选题In setting the valves on a steam-smothering system on a tanker，the master control valve to cargo tanks should be（）.Aopen and individual tank valves openBopen and the individual tank valves closedCclosed and the individual tank valves closedDclosed and the individual tank valves open