The lower section of a piston is called the ______.A.landB.crownC.skirtD.plate
The lower section of a piston is called the ______.
A.land
B.crown
C.skirt
D.plate
相关考题：
The lowest temperature at which the vapor formed from a liquid ignites and continues to burn steadily in the presence of an ignition source is called the( ). A.flash pointB.fire pointC.upper explosive limitD.lower explosive hmlt
The process during which liquid containing a reasonable amount of sensible heat at a particular pressure immediately changes into steam after admitted to a chamber at a lower pressure is called _____.A.boiling offB.flash evaporationC.condensationD.none of the above
The system of valves and cargo lines in the bottom piping network of a tanker that connects one section of cargo tanks to another section is called a ______．A.come-alongB.crossoverC.manifoldD.runaround
The section of each end of a barge which is heavily reinforced to take the pressure of pushing is called the ______．A.HeadlogB.TowheadC.Collision bulkheadD.Bullnose
The minimum temperature required to ignite gas or vapor without a spark or flame being present is called ______．A.Flash pointB.Fire pointC.Autoignition temperatureD.Lower explosive limit
The deck from bow to stern is called the （）(主甲板).A、main deckB、tweendeckC、upper deckD、lower deck
从船艏贯穿至船艉的甲板叫主甲板。（）A、The deck from bow to stern is called the main deck.B、The deck from stern to bow is called the tweendeck.C、The deck from bow to stern is called the upper deck.D、The deck from stern to bow is called the lower deck.
单选题The process during which liquid containing a reasonable amount of sensible heat at a particular pressure immediately changes into steam after admitted to a chamber at a lower pressure is called （）.Aboiling offBflash evaporationCcondensationDnone of the above
单选题The system of valves and cargo lines in the bottom piping network of a tank vessel that connects one section of cargo tanks to another section is called a（）.AcrossoverBrunaroundCcome-alongDmanifold
单选题The central longitudinal structural hull strength member of the lower hulls of semisubmersible ship’s is called the（）.Astress plateBkeelCrider plateDmain beam
单选题Oil control rings used in two-stroke/cycle diesel engines are located near the bottom of the piston skirt in order to （）Aincrease the liner area covered by the oil filmBmaintain an oil film on the lower liner where scuffing is prevalentCkeep excess oil away from intake and exhaust portsDhelp cushion piston skirt side thrust by providing a hydrodynamic oil wedge
单选题As to the piston cooling, of the following, which statement is not true?（）ABecause the piston is exposed to very high temperature, it must be cooledBThe lower the piston cooling temperature is, the better it isCBoth water and lube oil can be used as coolantDOne of the piston cooling methods is vibration cooling, with better effect
单选题The lower end of each piston rod is reduced in diameter to fit a bore in （）, this being secured to the piston rod by a nut.Athe crank-webBthe connecting rodCthe main bearingDthe cross-head
单选题The lower end of each piston rod is reduced in diameter to fit a bore in （）.Athe crossheadBthe journals of the crossheadCthe crosshead shoesDthe guides
单选题The lower end of each piston rod is reduced in diameter to fit a bore in the （）, this being secured to the piston rod by a nut.Apiston gudgeon pinBpiston skirtCcross-headDcross-head pin
单选题The cast iron guide-ways for （） are attached to the top section and seal off the crankcase.Athe connecting rodBthe cross-headCthe piston rodDthe air box
单选题The lower end of each piston rod is reduced in diameter to fit a bore in the cross-head, this being secured to the piston rod by （）.Aa boltBa capCa discDa nut
单选题Why is the ring belt narrower in diameter than the skirt of a piston designed for a diesel engine?（）ATo allow for greater expansion due to higher operating temperatureBTo seal the cylinder against leakage of combustion gasesCTo provide an additional surface for oil coolingDTo provide an additional strength for the crown and lower structure
单选题Which of the following statements concerning cylinder liner wear is true?（）ALiner wear is distributed equally between the upper and lower portions of the cylinderBExcessive liner wear causes wear between piston ring and grooveCExcessive, but uniform liner wear will not cause wear between piston ring and grooveDLiner wear is normally greatest in the middle of the cylinder
单选题The section of each end of a barge which is heavily reinforced to take the pressure of pushing is called the（）.AHeadlogBTowheadCCollision bulkheadDBullnose
单选题An aluminum piston has lower inertia and higher coefficient of （） compared to that of cast iron.AviscosityBtwisting momentsCinertiaDthermal expansion
单选题从船艏贯穿至船艉的甲板叫主甲板。（）AThe deck from bow to stern is called the main deck.BThe deck from stern to bow is called the tweendeck.CThe deck from bow to stern is called the upper deck.DThe deck from stern to bow is called the lower deck.