COMPETENCE 5

50問 • 2年前

Peter j Zuniega

通報

問題一覧

The ability of lubricating oil to resist viscosity changes during temperature changes is indicated by the________

viscosity index number

If the capacity of a centrifugal pump decreases gradually over a long period of time, you should replace the _____ .

wear rings

When securing a distillate pump on a low pressure fresh water evaporator, which of the listed steps should be carried out first?

Trip the threeway solenoid dump valve

A hydraulic system gear pump being fed from a reservoir frequently indicates signs of excessive pitting after two months of service. Which of the following would most likely contribute to this condition?

A vacuum condition has developed in the reservoir

The minimum delivery pressure required for diesel engine fuel oil injection depends primarily on the ___________.

firing pressure in the engine

Fuel oil penetration into the cylinder of a diesel engine is ___________.

reduced by finer atomization

Which of the following precautions should be observed concerning the introduction of a fire resistant fluid into a hydraulic system?

Deterioration of paints, seals, metals, and electrical insulation may occur.

A good quality oil used in main propulsion engine lubrication systems should be _____________.

resistant to permanent emulsification

Fuel supplied by each unit injector on a two stroke cycle single acting diesel engine is directed into each cylinder at a very high pressure through the ___________.

spray tip of the injector

Very small irregularities on the seat and disk of a globe valve may be manually repaired with the valve in place by the process known as _____________.

lapping in

When assembling a run of liquid service piping, which of the following factors should be considered? I. How the type of fittings used will affect the flow II. What type of gasket material should be used III. What radius should be used for each bend in the

A. I, II & III

The injection pressure of a hydraulic fuel injection nozzle can be increased by _______.

increasing compression on the pressure spring

Zinc anodes are installed in a marine raw‐water cooling system to _____________.

control electrolysis

To correctly identifies the position of the journal when the shaft is ______.

just beginning to rotate

A vacuum condition has developed in the reservoir

The minimum delivery pressure required for diesel engine fuel oil injection depends primarily on the ___________

firing pressure in the engine

Fuel oil penetration into the cylinder of a diesel engine is ___________.

reduced by finer atomization

Which of the following precautions should be observed concerning the introduction of a fire resistant fluid into a hydraulic system?

Deterioration of paints, seals, metals, and electrical insulation may occur.

A good quality oil used in main propulsion engine lubrication systems should be _____________.

resistant to permanent emulsification

Fuel supplied by each unit injector on a two‐stroke cycle single acting diesel engine is directed into each cylinder at a very high pressure through the ___________.

spray tip of the injector

Very small irregularities on the seat and disk of a globe valve may be manually repaired with the valve in place by the process known as _____________.

lapping in

The injection pressure of a hydraulic fuel injection nozzle can be increased by _______.

increasing compression on the pressure spring

Zinc anodes are installed in a marine raw‐water cooling system to _____________.

control electrolysis

Main propulsion engine lube oil sumps should be constructed _________.

with a sloped bottom

The amount of fuel injected into a diesel engine cylinder by a unit injector, is controlled by ___________.

a metering helix inside the pump

Gate valves should not be used for throttling as __________.

wire drawing of the disc will result

f the chemical analysis of a lube oil sample taken from the main propulsion machinery indicates an increased neutralization number the _______.

acidity has increased

Assuming oil and water flow rates remain the same, what would be the effect of scale formation occurring on the inside of the cooling water tubes of a lube oil heat exchanger?

water temperature outlet temperature will decrease and the lube oil temperature will increase

The combustible element in fuel that could cause major air pollution is _______.

sulphur

The viscosity of fuel oil is indicated by its____________.

internal friction

The final heating of the feedwater in a flash type distilling plant is carried out by______.

low pressure steam admitted to the feedwater heater

Which of the listed conditions can lead to cavitation in a centrifugal pump?

Vapor pockets formed in the suction flow stream

If you attempt to tighten a leaking hydraulic fitting with pressure on the system, you will _____.

find that the pressure will prevent the components from being tightened

To correctly identifies the position of the journal when the shaft is ______.

just beginning to rotate

Tube scaling in heat exchangers causes the heat transfer rate to decrease because the _____.

thermal conductivity of the scale is very low

While the oilywater- seperator is operating in the processing mode, if a low vacuum, what is the probable cause?

The coalescer beads are severely fouled

The harmful effect of sulfur present in the boiler fuel oil is that it ___________.

forms corrosive acids when mixed with water

What do next after adding grease to a ball bearing with a hand held grease gun?

Run the machine with the bearing housing drain plug open for a short while

What happen when you heat the oil?

It makes the oil less viscous

What instrument or process determines the BTU value of boiler fuel oil?

Calorimeter

Greases are generally produced by ____.

saponifying a metal base, to which oil is then added and mixed under controlled temperature

If one of the bilge system manifold valves does not properly seat, the__________.

bilge system will lose vacuum and prevents the other bilges from being pumped out

When securing a centrifugal type distillate pump, which of the listed steps should be carried out first?

Trip the three way dump valve

Which of the following statements represents the proper relative direction of flow through a globe valve?

Direction of flow should be from below the seat

In a two stage flash evaporator, heated feedwater is vaporized in the_________.

first and second stage flash chambers

In a centrifugal pumps operating with a high suction lift, foot valves are primarily designed to______. .

enable the pump and its suction line to remain primed prior to starting the pump

Which of the following centrifugal pump components converts the liquid velocity to pressure?

Volute

An oil fog lubrication system is recommended for______.

high speed continuous operation of roller bearings

The first step when beginning to set the slide valves on a duplex reciprocating pump is to _____

center the steam piston in the cylinders

If you are operating a centrifugal water service pump with worn wear rings, the____

pump discharge capacity is reduced

COMPETENCE 1