更多"The exhaust valve opens before bott"的相关试题:
[单项选择]When the relief valve opens it discharges high pressure refrigerant vapor to the （）.
A. liquid strainer
B. refrigerant inlet of the condenser
C. inlet side of the evaporator
D. suction side of the compressor
[单项选择]At bottom dead center, the centerline of the connecting rod usually coincides with the（）
A. angularity of the piston motion
B. inertia moment from the piston
C. centerline of the cylinder
D. centerline of the king pin
[单项选择]A piston is at bottom dead center when it is（）
A. opening the exhaust ports
B. closing the fuel ports
C. farthest from the cylinder head
D. nearest to the cylinder head
[单项选择]
In a diesel engine, exhaust valves open before the intake ports are uncovered to （）
Ⅰ.reduce pumping losses
Ⅱ.reduce back pressure
A. Ⅰonly
B. Ⅱonly
C. bothⅠand Ⅱ
D. neitherⅠnor Ⅱ
[单项选择]The high-pressure fuel opens the fuel valve and is sprayed into the cylinder in tiny droplets known as （）.
A. injection
B. penetration
C. atomization
D. compression
[单项选择]A piston is said to be at top dead center when it is （）
A. opening the exhaust ports
B. placed on top of the engine along its centerline
C. farthest from the cylinder head
D. nearest to the cylinder head
[单项选择]Increasing the valve clearance between a valve stem and rocker arm, will result in the valve （）
A. closing later
B. opening sooner
C. staying open for a shorter period of time
D. staying open for a longer period of time
[单项选择]The needle valve in a fuel valve will （） when the fuel pressure action on the needle valve tapered face exerts a force lower than that of the spring compression.
A. be jammed
B. be opened
C. be seated
D. be broken
[单项选择]A more sophisticated pressure reducing valve incorporates a pilot valve which controls the fluid above the valve operating piston in response to downstream pressureThe bold and italic word “which” means （）.
A. a pressure reducing valve
B. a pilot valve
C. an operating piston
D. downstream pressure
[单项选择]A thermostatic expansion valve is properly controlling evaporator superheatAdjusting this valve to lower the superheat will result in a/an （）.
A. evaporator pressure decrease
B. evaporator coil over-feed
C. evaporator capacity increase
D. expansion valve diaphragm rupture
[单项选择]Thermostatic expansion valve are （）.
A. either all the way open or all the way closed
B. normally open
C. throttled depending on load
D. controlled by suction pressure
[单项选择]Overflow valve is used to （）
A. control the fluid flow through it
B. prevent the pressure before it over the specified valve
C. make the pressure after it steady
D. control the direction of oil flow
[单项选择]During working, thermostatic expansion valve should be （）.
A. either all the way open or all the way closed
B. normally fully open
C. throttled depending on load
D. controlled by liquefied pressure
[单项选择]The part of a fuse that melts and opens the circuit is made of （）.
A. copper and antimony
B. steel and babbitt
C. aluminum or beryllium alloy
D. zinc or an alloy of tin and lead
[单项选择]Valve的中文含义是（）。
A. 电压
B. 电阻
C. 电容
D. 电流
[单项选择]As the refrigerant passes through the valve orifice, its pressure is reduced and part of the refrigerant turns into （）.
A. liquid
B. oily mixture
C. emulsion
D. vapor
[单项选择]The emergency bilge suction valve is typically used （）.
A. to inject cleaning additives when the bilges are extremely dirty
B. when the main condenser becomes fouled, in order to provide additional cooling water circulation
C. to connect the rose box to the independent bilge suction
D. if the bilges become flooded and they can not be emptied by any other means
[单项选择]The mechanical exhaust valve operation system is replaced by（）in an electronic controlled ME engine.
A. a system with a Hydraulic Power Supply (HPS) unit
B. a system with roller guides for exhaust valves
C. a system with an electronically controlled Alpha Lubricator
D. a system directly powered by electric motor
