更多"When to remove scale from the cooli"的相关试题:
[单项选择]Head tank should be used to remove （） from cooling water.
A. scale
B. sludge
C. chemicals
D. air
[单项选择]It is necessary to remove （） from the cooling water spaces to improve heat transfer.
A. lime
B. frost
C. scale
D. scar
[单项选择]It is necessary to remove （） from the cooling spaces.
A. scar
B. scale
C. spur
D. bilge
[单项选择]When fighting fires in spaces containing bottles of LPG (liquefied petroleum gas)，you should （）.
A. attempt to isolate the fire from the LPG
B. cool the bottles or remove them from the fire area
C. see that the valves on all LPG bottles are closed
D. place insulating material over the bottles
[单项选择]When the machinery spaces are in the periodic unmanned condition, shall be immediately available and on call to attend the machinery space（）.
A. the chief engineer
B. the designated engineer from shipyard
C. the designated duty officer in charge of the engineering watch
D. the designated surveyor from classification society
[单项选择]When the chief engineer is in the machinery spaces, the officer in charge of the engineering watch shall（）
A. continue to be responsible for machinery space operations despite the presence of the CE
B. hand over the responsibility actively
C. be responsible for the watching together with the chief engineer
D. assistant the chief engineer to control the machinery
[单项选择]When considering a vessel’s stability，which spaces in a general cargo vessel are the best locations for the carriage of bulk grain? （）
A. Deep tanks
B. Lower holds
C. Lower holds at the ends of the vessel
D. 'Tween-decks
[单项选择]These acid residues must be prevented from entering the crankcase, otherwise the lube oil would be（）
A. contaminated
B. emulsified
C. deteriorated
D. oxidated
[单项选择]When winds of force reach 10-11 in Beaufort Scale，usually we call such winds as（）.
A. Hurricane
B. Breeze
C. Storm
D. Gale
[单项选择]EXCEPT when suffering from a head or chest injury a patient in shock should be placed in which position?（）.
A. Head up and feet down
B. Head down and feet up
C. Flat on back with head and feet elevated
D. Arms above the head
[单项选择]When viewed from astern, if the propeller revolves in a clockwise direction when going ahead, it is known as （）.
A. ahead direction
B. astern direction
C. right-handed
D. left-handed
[单项选择]When transferring survivors from an enclosed lifeboat to a rescue vessel，personnel on board the boat should（）.
A. remove their life preservers to make it easier to climb on board the rescue vessel
B. climb on top of the boat while waiting for their turn to transfer to the rescue vessel
C. remain seated inside and make the transfer one person at a time
D. enter the water and swim over to the rescue vessel
[单项选择]When changing from a compass course to a true course you should apply（）.
A. variation
B. deviation
C. variation and deviation
D. a correction for the direction of current set
[单项选择]When entering from seaward，a buoy displaying a single-flashing red light would indicate （）.
A. a junction with the preferred channel to the left
B. a sharp turn in the channel to the right
C. the starboard side of the channel
D. a wreck to be left on the vessel's port side
[单项选择]Acid solution（） in the system can be tested from time to time by putting some on to a piece of lime.
A. strength
B. dense
C. percentage
D. velocity
[单项选择]When viewed from above，the best position for the guy in relation to the boom is（）.
A. At a 45° angle
B. At right angles
C. 4 feet aft of the heel of the boom
D. Parallel to the boom
[单项选择]When discharging oil from an oil tanker the instantaneous rate（）60 liters per nautical mile.
A. Should not exceed
B. Must be up to
C. Should exceed
D. Should be about
[单项选择]When approaching Block Island Sound from Long Island Sound，you will enter waters governed by the International Rules of the Road when you（）.
A. pass through The Race
B. cross the territorial sea boundary
C. exit Block Island Sound to the east or south
D. None of the above，as Long Island Sound is governed by the International Rules of the Road
[单项选择]When the water produced from most evaporator is supplied for drinking purpose, it must be treated to ensure it is biologically pure and （）.
A. slightly acidic
B. slightly alkaline
C. no salty
D. slightly bitter
