A . cooling water pump
B . nozzle cooling passages
C . cylinder jackets
D . heat exchanger
[单选题]Bottom blow valves are installed on auxiliary water-tube boilers to ()A . remove suspended and precipitated solids from the boiler waterB . completely drain the boiler in an emergency situationC . prevent hardened scale deposits in the water drumD .
[试题]A.ftertherobbery,theshopinstalledasophisticatesalarmsystemasaninsurance_________furtherlosses.A.)forB)fromC.)againstD)towards
[单选题]A. new Ezonexam switch is installed into an existing LAN and a new VTP trunk is set up with an existing switch. Which VLANs will be allowed on this new trunk?A.All defined VLANs are allowed on the trunk by default.B.Each VLAN, or VLAN range, that is
[单选题]Fins are installed on the generating tube surfaces in waste heat boilers to ().A . prevent soot fires in the exhaust systemB . prevent exhaust gas erosion of the tubesC . increase the velocity of exhaust gas flowD . increase the rate of heat transfer
[单选题]The intake valves in a diesel engine are reseated by ().A . cam followersB . push rodsC . combustion gasesD . valve spring
[单选题]The purpose of the safety relief valves installed on an auxiliary boiler is to ().A . relieve excess fuel oil pressure during the “off” fire cycleB . admit water to the dry pipeC . throttle the forced draft fan output for proper combustio
[单选题]F.usible plugs are installed in fire-tube boilers to _____.A.provide a means of draining the boilerB.warn the engineer of low water levelC.cool the crown sheet at high firing ratesD.open the burners electrical firing circuits
[单选题]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
[主观题]why is quick closing valves important to in engine room machineries ?how are they operated ?
[单选题]During (), the starting air valves should be closed to prevent the engine from turning.A . overhaulB . runningC . blowing downD . All of the above are correct