單項選擇題In the presence of an open flame or hot surfaces, chlorinated fluorocarbon refrigerants decomposes and from （）

A.petroleum crystals
B.phosgene gas
C.water vapor
D.carbon monoxide


您可能感興趣的試卷

你可能感興趣的試題

1.單項選擇題In an operating refrigeration system low on refrigerant, a liquid line sight glass will（）

A.be clear
B.be blue
C.be light green
D.show bubbles

2.單項選擇題The thermal expansion valve reacts directly to the （）

A.temperature in the space being cooled
B.liquid refrigerant pressure at the solenoid valve
C.pressure drop across the evaporator coils
D.refrigerant gas superheat at the coil outlet

3.單項選擇題When transmitted by a reduction gear, diesel engine speed is reduced and the torque available for work （）

A.remains the same
B.is reduced
C.is increased
D.is eliminated

4.單項選擇題Pitting in the area close to the pitch line and on the same end of each gear tooth of a reduction gear unit would be caused by （）

A.corrosion on the gears
B.excessive gear speed
C.dirt in the oil
D.misalignment of the gears

5.單項選擇題When used with reversing reduction gears, medium-speed diesel engines should be bolted to their foundations with fitted bolts at the drive end and clearance(loosely fitted) bolts in other locations √This is done to （）

A.maintain alignment when the ship’s hull is working in heavy seas
B.ensure engine vibrations correspond to the natural frequency of the hull
C.permit the engine to expand away from the driven equipment as the engine heats up and expands
D.maintain engine thrust bearing clearances

最新試題

If two A.C.generators are to be operated in parallel, the load is distributed evenly by（）

題型：單項選擇題

The flash point of a residual fuel oil should be used to determine the highest temperature to which oil may be heated（）

題型：單項選擇題

When does auxiliary burner of incinerator put into operation? （）Ⅰ. start incinerator when it is coldⅡ. the sludge for dealing with is littleⅢ. the sludge for dealing with is largeⅣ. the water and impurity in sludge are too muchⅤ. the temperature in incinerator is lowⅥ. dealing with little solid rubbish

題型：單項選擇題

The additional mark （）in the Classification Certificate for Machinery means propulsion apparatus is remotely controlled on the navigating bridge control station, and engine assembly control station is unmanned periodically.

題型：單項選擇題

“Insufficiency of manning or insufficiency of certification of seafarers” is an identification of a（）

題型：單項選擇題

Which of the listed governor characteristics will greatly affect the load sharing relationship between paralleled diesel generators?（）

題型：單項選擇題

Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）

題型：單項選擇題

The condensers located in various stages of a flash evaporator are cooled by（）

題型：單項選擇題

Flame failure in an automatically fired auxiliary boiler can from a/an （）

題型：單項選擇題

To shut down a diesel engine after it exceeds the set maximum speed，which type of device listed should be used?（）

題型：單項選擇題