______continuously extract the crankcase atmosphere, via a pipe system, and move it past a sensitive and accurate opacity (不透明)measuring track.

试卷相关题目

• 1The maximum pressure developed by a waste heat boiler is determined by the main engine exhaust ______.

  A.gas composition

  B.gas temperature

  C.pressure

  D.timing

  开始考试点击查看答案
• 2A controllable pitch propeller on a diesel driven vessel eliminates the need for ______.

  A.friction clutches

  B.disconnect clutches

  C.reversing gears

  D.reduction gears

  开始考试点击查看答案
• 3Before a marine diesel engine is started the cylinders and pistons must be ______.

  A.cooled to appropriate temperature

  B.warmed up gradually to appropriate temperature

  C.opened up and renewed

  D.ground and polished

  开始考试点击查看答案
• 4A dirty diesel engine oil filter element can best be detected by ______.

  A.visual inspection of the elements

  B.the pressure drop across the filter

  C.high lube oil sump temperature

  D.decrease in oil viscosity from the filter

  开始考试点击查看答案
• 5The total starting air capacity required for reversible main engines is to be sufficient for a least ______.

  A.six consecutive(连续的) starts

  B.eight consecutive starts

  C.ten consecutive starts

  D.twelve consecutive starts

  开始考试点击查看答案
• 6The water in a steaming auxiliary boiler should be tested daily for ______.

  A.dissolved oxygen

  B.chlorides

  C.sludge

  D.dissolved nitrogen

  开始考试点击查看答案
• 7A firebox explosion in an automatically fired auxiliary boiler may be the result of ______.

  A.excessive purging before lighting off

  B.insufficient trail for ignition period

  C.a faulty transformer in the ignition circuit

  D.insufficient purging after lighting off

  开始考试点击查看答案
• 8A feed pump for an auxiliary boiler might lose suction if the ______.

  A.boiler water level is low

  B.feed-water is too hot

  C.boiler steam demand is low

  D.feed-water is too cold

  开始考试点击查看答案
• 9The gear and screw pumps are classified as______.

  A.variable stroke pumps

  B.multistage pumps

  C.positive displacement pumps

  D.triple-ported pumps

  开始考试点击查看答案
• 10The pressure of a liquid leaving the pump can be referred to as the ______.

  A.total head

  B.discharge head

  C.net positive suction head

  D.suction head

  开始考试点击查看答案