A.proper combustion
B.water in the fuel
C.excess air
D.cold fuel oil
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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 hand-hole/manhole covers should be tightened up as much as possible to preclude any leaks
D.All of the above
A.The boiler oil tank
B.The steam pipe
C.The fire side
D.The safety valves
A.oxygen in the water
B.poor boiler design
C.density too high
D.excessive steam demand
A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame
A.condensate
B.a small amount of make-up feed
C.A and B
D.None of the above
A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame
A.low water level
B.low oil pressure
C.excessively high fuel pressure
D.an improper air/fuel ratio
A.Reciprocating pump
B.Screw pump
C.Diffuser pump
D.Water-ring pump
A.discharge is continuous
B.it has no internal valves
C.upon accidental closing of discharge valve, excessive pressure will not build up
D.all of the above are true
A.between the suction and discharge
B.below the liquid supply
C.above the liquid supply
D.any of the above
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When the steering gear is in operation, you should ().
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An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of ().
A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by ().
The major source of chemical contaminants in hydraulic fluid is ().
Low compressor head pressure in a refrigeration system can be caused by().
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?()
An excessive charge of refrigerant in an air-cooled refrigeration system can cause ().
On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is ().