MACHINIST MATE PRACTICE
EXAMINATION 2026 QUESTIONS WITH
ANSWERS GRADED A+
◍ Main engine thrust bearing is normally what type?.
Answer: Kings bury pivoted segmental she type
◍ Charles' lawTVC.
Answer: if volume constant then pressure and temperature are directly
proportional/ if pressure unchanged then volume and absolute temperature
are directly proportional
◍ What type of pump is used to remove brine from an evaporator brine
circuit?.
Answer: Centrifugal pump
◍ For a steam jacketed kettle, what is maximum steam pressure?.
Answer: 45 psi
◍ What at prohibits any person to discharge oil from any water borne vessel or
ashore or offshore facility into/upon certain waters and established
restrictions within contiguous zone.
Answer: Federal water pollution act 1970
◍ What is QA chapter 13?.
Answer: Wire removal and replacement
◍ What is the required reduction gear tooth contact for an SSTG with helical
gears?.
Answer: 80% of fave width
◍ Flash point tester stirring mechanism rotates at what speed?.
Answer: 90-120 rpm
,◍ After all refrigerant leaks have been found and corrected, system must hold
system pressure for what duration?.
Answer: Six hours with zero loss of pressure
◍ Turbine lagging pads must be verified as non asbestos by using what
guidance?.
Answer: NSTM 635
◍ Min flash point of F-76?.
Answer: 140 degrees
◍ What type of availability is used for repairs while ship is underway?.
Answer: Voyage repair availability
◍ turbine rotor assembly consists of what.
Answer: turbine rotor blade-extract energy from expanding gases and transit
to rotor diskturbine rotor diskturbine rotor shaft
◍ During loss of vacuum casualty on a main condenser, what action must be
taken when vacuum decreases to 15"?.
Answer: Main engine must be stopped and casualty procedure IAW EOCC
◍ Air lock is designated to hold for what min time frame IAW PMS.
Answer: 10mins
◍ barometric pressure.
Answer: 29.92 inches of mercury or 14.7 PSI
◍ What is the composition of copper nickel alloy tubing used on surface ships
?.
Answer: 90% copper 10% nickel
◍ Max journal bearing temp on operating main engine or SSTG as indication
by RTE.
Answer: 250 degrees
◍ How is hard fouling removed from heat exchangers?.
Answer: High pressure water jet and cleaning
, ◍ A reduction gear journal bearing shows dramatic increase in temp and then
decrease to ambient temp, this is called what?.
Answer: Wiped bearing
◍ What device is installed on main engine thrust bearing to indicate flow?.
Answer: Sight flow indicator
◍ How is turbine speed maintained during jammed throttle casualty?.
Answer: By using affected turbine guarding valve
◍ What QA for is used for testing and inspection?.
Answer: QA form 17
◍ Required RPM for BS&W.
Answer: 1500 RPM
◍ How often are main propulsion boilers inspected?.
Answer: 18 months
◍ Exit guide vanes.
Answer: straighten the airflow to reduce the airflow turbulence as it comes
out of the compressorlocated at end of compressor section
◍ The centrifuge is operated in what time intervals during centrifuge testing.
Answer: 30 min intervals
◍ What type of viscometer is commonly used to determine fuel oil and fuel
viscosity?.
Answer: Say bolt viscometer
◍ When warming up steam assisted atomizers, how long do you allow for
warmup with steam prior to light off?.
Answer: 3-5 mins
◍ thermocouples.
Answer: produce electrical signal in propulsion to exhaust gas
temperatureit's a temperature sensor
◍ ConductionHeat Method.
EXAMINATION 2026 QUESTIONS WITH
ANSWERS GRADED A+
◍ Main engine thrust bearing is normally what type?.
Answer: Kings bury pivoted segmental she type
◍ Charles' lawTVC.
Answer: if volume constant then pressure and temperature are directly
proportional/ if pressure unchanged then volume and absolute temperature
are directly proportional
◍ What type of pump is used to remove brine from an evaporator brine
circuit?.
Answer: Centrifugal pump
◍ For a steam jacketed kettle, what is maximum steam pressure?.
Answer: 45 psi
◍ What at prohibits any person to discharge oil from any water borne vessel or
ashore or offshore facility into/upon certain waters and established
restrictions within contiguous zone.
Answer: Federal water pollution act 1970
◍ What is QA chapter 13?.
Answer: Wire removal and replacement
◍ What is the required reduction gear tooth contact for an SSTG with helical
gears?.
Answer: 80% of fave width
◍ Flash point tester stirring mechanism rotates at what speed?.
Answer: 90-120 rpm
,◍ After all refrigerant leaks have been found and corrected, system must hold
system pressure for what duration?.
Answer: Six hours with zero loss of pressure
◍ Turbine lagging pads must be verified as non asbestos by using what
guidance?.
Answer: NSTM 635
◍ Min flash point of F-76?.
Answer: 140 degrees
◍ What type of availability is used for repairs while ship is underway?.
Answer: Voyage repair availability
◍ turbine rotor assembly consists of what.
Answer: turbine rotor blade-extract energy from expanding gases and transit
to rotor diskturbine rotor diskturbine rotor shaft
◍ During loss of vacuum casualty on a main condenser, what action must be
taken when vacuum decreases to 15"?.
Answer: Main engine must be stopped and casualty procedure IAW EOCC
◍ Air lock is designated to hold for what min time frame IAW PMS.
Answer: 10mins
◍ barometric pressure.
Answer: 29.92 inches of mercury or 14.7 PSI
◍ What is the composition of copper nickel alloy tubing used on surface ships
?.
Answer: 90% copper 10% nickel
◍ Max journal bearing temp on operating main engine or SSTG as indication
by RTE.
Answer: 250 degrees
◍ How is hard fouling removed from heat exchangers?.
Answer: High pressure water jet and cleaning
, ◍ A reduction gear journal bearing shows dramatic increase in temp and then
decrease to ambient temp, this is called what?.
Answer: Wiped bearing
◍ What device is installed on main engine thrust bearing to indicate flow?.
Answer: Sight flow indicator
◍ How is turbine speed maintained during jammed throttle casualty?.
Answer: By using affected turbine guarding valve
◍ What QA for is used for testing and inspection?.
Answer: QA form 17
◍ Required RPM for BS&W.
Answer: 1500 RPM
◍ How often are main propulsion boilers inspected?.
Answer: 18 months
◍ Exit guide vanes.
Answer: straighten the airflow to reduce the airflow turbulence as it comes
out of the compressorlocated at end of compressor section
◍ The centrifuge is operated in what time intervals during centrifuge testing.
Answer: 30 min intervals
◍ What type of viscometer is commonly used to determine fuel oil and fuel
viscosity?.
Answer: Say bolt viscometer
◍ When warming up steam assisted atomizers, how long do you allow for
warmup with steam prior to light off?.
Answer: 3-5 mins
◍ thermocouples.
Answer: produce electrical signal in propulsion to exhaust gas
temperatureit's a temperature sensor
◍ ConductionHeat Method.
