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|of the impurities commonly found in marine lubricating oil, which of the following can NOT be removed by a centrifugal purifier at normal operating temp?
|if a soot blower element does not revolve freely, the most likely cause would be ________.
|war-page of the soot blower element
|a rapid fluctuation of the supper heater outlet temp on a steady steaming boiler could indicate___________.
|water carryover into the supperheater
|a boiler safety valve must be capable of_______.
|remaining open until a preset pressure drop occurs
|when a boiler water test indicates a pH value of 6, you should_______.
|chemically treat to raise the pH to normal level
|coast guard reg (46 CFR) requires machinery driving the fuel oil transfer and fuel oil service pumps to be fitted with a remote means of stopping the machinery___________.
|outside of the space concerned
|which of the listed items are the two most commonly used opposing forces involved in the operation of a constant pressure feed pump governor?
|pump discharge pressure and adjusting spring compression
|shortly after shutting off the fuel to a boiler which is to be secured, the___________.
|burner registers should be closed
|which of the pumps is normally used in fuel oil service systems?
|positive displacement rotory
|design characteristics of a velocity-compounded impulse turbine include the utilization of _______.
|a single pressure stage with two or more velocity stages
|if live steam is supplied directly to the tank heating coils, the collected drains in the "clean" section of the contaminated drains tank are removed directly to the _________.
|atmospheric drain tank
|failure to use the turning gear prior to warming up a main turbine will damage the ______.
|to avoid pulsations of the burner flame after rebuilding the boiler burner front tile refractory,_______.
|the burner tile should fitted to the throat ring rather than the surrounding brick work
|what refractory materials may be used with other machinery insulation arrangements outside of the boiler?
|the high pressure steam drain system is normally collected by the ________.
|deaerating feedwater heater
|coast guard reg (46 CFR) for boiler fuel oil service systems, require that _____________.
|the return line from the burners must be arranged so that suction piping cannot be subject to discharge pressure
|the FIRST step in breaking vacuum on a main turbine unit should be to __________.
|secure the steam to the main air ejector
|in a boiler where the drum water level is automatically controlled, which of the following conditions could cause erratic variations in the water level?
|high total dissolved solids content and foaming in the drum
|main steam turbine bearings are lined with _________.
|to comply with coast guard reg (46 CFR) which type of boiler listed shall be subjected to a hydrostatic test at one and one half times max allowable working pressure?
|all water-tube boilers to which extensive repairs have been made
|a turbine assembly in which steam flows in a series through a HP turbine and then on to a LP turbine, with both turbines driving a common reduction gear through separate shafts, is classed as _____.
|the sentinel valve located on the LP turbine casing is designed to _________.
|warn the engineer of excessive pressure in the LP casing
|the max temp rise of oil passing through any reduction gear set, or bearing, should not exceed ______.
|50 deg F (27.8 deg C)
|panting or rumbling in a boiler furnace is usually caused by ________.
|not enough air
|prolonged astern operations of a turbine will cause ______.
|overheating of ahead stages
|in a marine boiler, max heat transfer rates can be obtained by ______.
|keeping the watersides free from scale deposits
|the main feed check valve functions to __________.
|prevent back flow of water from the boiler in the event of feed pump failure
|rapid discharge condensate into the DC heater during normal steaming conditions could cause _____.
|decrease in aux exhaust pressure
|the possibility of a flareback in a boiler will be reduced if you ________.
|purge the furnace with fresh air prior to lighting off
|two-element feedwater regulators operate by sensing _________.
|boiler water level and steam flow
|an obstruction in the top connection of a boiler gage glass will cause the __________.
|water level to to rise slowly in the glass
|condensation accumulation in the steam side of a fuel oil heater could result in _______.
|reduced heating capacity in an operating heater
|a turbo-generator back pressure trip can be actuated as a result of __________.
|insufficient circulating water flow through the condenser
|thin tipping is a type of turbine blade design primarily used to ______.
|reduce losses due to blade tip leakage in reaction turbines
|what is one of the devices found on a LP main propultion steam turbine casing?
|reaching which "end point" will result in the most sever damage to the boiler?
|which possible condition has occurred if a vacuum is present at the atmospheric drain tank vent while the vessel is underway
|the control valve regulating flow to the main condenser is stuck in an open position
|in some lube oil systems, the temp of the lube oil downstream from the lube oil cooler is directly regulated by ________.
|a thermostatically controlled valve which bypasses oil around the cooler
|how is diaphragm type steam whistle protected from damage due to entrained condensation?
|a water separator is installed in the steam supply line
|the term "separation " as used in oil purification refers to the removal of _________.
|two liquids from eachother
|if you noted a large difference in the pressures indicated by a duplex pressure gage to the fuel oil system strainer, you should ________.
|shift to a clean fuel oil strainer
|if while filling the boiler a newly installed gasket on a water-tube hand hole plate weeps, you should ______.
|center and tighten with correct size wrench
|in which of the following types of condensers would you find the cooling water passing through tubes with the turbo-generator exhaust steam directed around the outside of the tubes?
|as lube oil absorbs moisture its dielectric strength can be expected to ________.
|the formation of a pit in the surface of a boiler tube is most likely to occur when ________.
|the tube acts as an anode