Power Engineer Class 4 Certificate
Part B ALL QUESTIONS COMPLETE
AND CORRECT ANSWERS
\Q\.The resistance of a liquid to internal deformation or shear is known as: - ANSWERS✔-
Viscosity
\Q\.If an oil must flow at a very low temperature, it must have the following additive: -
ANSWERS✔-Pour point depressant
\Q\.An anti-friction bearing: - ANSWERS✔-Has rolling friction
\Q\.The ability of an oil to lift and support heavy loads depends upon: - ANSWERS✔-Hydraulic
pressure
\Q\.Which type of oil produces higher fluid friction? - ANSWERS✔-High viscosity oil
\Q\.A shell type bearing: - ANSWERS✔-Is used for heavy loads
\Q\.A journal bearing: - ANSWERS✔-Supports a shaft
\Q\.If ambient air temperatures are very low, the preferred lubricant is a: - ANSWERS✔-Solid
\Q\.A normal anti-friction bearing temperature operating range is: - ANSWERS✔-65°C to 70°C
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\Q\.Which of the following has the greatest effect on the viscosity of lubrication oil? -
ANSWERS✔-Temperature
\Q\.Where gear teeth inter-mesh, a lubricant must provide - ANSWERS✔-Shock absorption
\Q\.The lubricant for an anti-friction bearing: - ANSWERS✔-Could be a semi-solid lubricant
\Q\.A rotary pump: - ANSWERS✔-Should be equipped with a relief valve
\Q\.When a pump discharges into a vessel operating at 300 kPa, the 300 kPa is referred to as: -
ANSWERS✔-Pressure head
\Q\.Sliding vane compressors: - ANSWERS✔-Are positive displacement compressors
\Q\.A pump is capable of suction lift due to: - ANSWERS✔-Atmospheric pressure
\Q\.The compressor that would favour volume over pressure would be the: - ANSWERS✔-
Centrifugal
\Q\.The name given to the category of pumps that use gear teeth, vanes, or lobes to move the
fluid being pumped is the _____ type. - ANSWERS✔-Rotary
\Q\.A diffuser pump: - ANSWERS✔-Is more effective at changing velocity to pressure than a
volute pump
\Q\.It is generally accurate to say that: _____________ results from every metre of water depth
or height - ANSWERS✔-9.8 kPa pressure
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\Q\.The capacity of a centrifugal pump should only be reduced by: - ANSWERS✔-Throttling the
discharge valve
\Q\.Which of the following air compressors gives two compression strokes per crankshaft
revolution? - ANSWERS✔-Single cylinder double acting compressor
\Q\.Centrifugal pump power requirements are decreased when: - ANSWERS✔-The mass of fluid
delivered is decreased
\Q\.The difference between static suction head and static discharge head is: - ANSWERS✔-Total
static head
\Q\.A reciprocating air compressor works on the principle of: - ANSWERS✔-Volume reduction
\Q\.A low water fuel cutoff on an unattended steam boiler shall be installed so that -
ANSWERS✔-It cannot be rendered inoperative
\Q\.A low fire start switch: - ANSWERS✔-Acts as a pre-ignition interlock to ensure minimum
damper setting during ignition
\Q\.When differential pressure is used to measure water level in a boiler steam drum, the
differential pressure is: - ANSWERS✔-Greatest when drum level is low
\Q\.A high gas pressure fuel cut-off switch: - ANSWERS✔-Prevents excessive fuel pressure from
creating an unstable flame condition
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\Q\.The discharge pipe from a boiler safety valve is supported independently of the safety valve:
- ANSWERS✔-So the discharge pipe can expand without putting force on the safety valve
\Q\.The minimum DN size of the blowoff piping of a steam heating boiler is: - ANSWERS✔-20
mm
\Q\.When an automatic unattended boiler starts up, the programming control will first: -
ANSWERS✔-Start the forced draft fan
\Q\.The prime importance of boiler fittings is: - ANSWERS✔-Safety & efficiency
\Q\.If a safety valve leaks after a try lever test, the operator should: - ANSWERS✔-Operate the
try lever several times to blow away foreign material
\Q\.Thermocouples are connected in series to: - ANSWERS✔-Generate a higher voltage
\Q\.The safety valves on a boiler are set to open at 1380 kPa. The boiler MAWP is 1380 kPa.
How much higher can the boiler pressure rise above 1380 kPa, if it is fired at full capacity with
the steam outlet valve closed? - ANSWERS✔-82.8 kPa
\Q\.Transparent gauge glasses are lined with mica to: - ANSWERS✔-Protect the glass
\Q\.If a steam boiler is in service and no water level shows in the gauge glass, the first action
would be to: - ANSWERS✔-determine whether the gauge glass is completely full or completely
empty.