更多"When the relief valve opens it disc"的相关试题:
[单项选择]
The exhaust valve opens before bottom dead center in a four stroke engine to（）
Ⅰ.allow for blow down
Ⅱ.Reduce pumping losses
A. Ⅰ only
B. Ⅱ only
C. both Ⅰ and Ⅱ
D. neither Ⅰ nor 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]The needle valve will open when the fuel pressure acting on the needle valve （） exerts a sufficient force to overcome the spring compression.
A. tape face
B. tapered face
C. surface
D. thinner face
[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]The period of valve overlap is when （）.
A. the inlet valve is open
B. the exhaust valve is open
C. both valves are close
D. both valves are open
[单项选择]When the starting air valve closes on one cylinder, another starting air valve has （） opened on another cylinder whose piston has just commenced its downward stroke.
A. just
B. nearly
C. merely
D. already
[单项选择]When a high pressure system is centered north of your vessel in the Northern Hemisphere（）.
A. You should experience hot，moist，clear weather
B. The wind direction is generally easterly
C. The winds should be from the southwest at your location
D. The winds should be brisk
[单项选择]When you adjust a thermostatic expansion valve, （）.
A. refrigerant must be bled off the sensing line before adjustments are made
B. all refrigerant must be pumped into the receiver before adjustments are made
C. time must be allowed for conditions to stabilize in the evaporator before further adjustments are made
D. all refrigerant must be routed through the dehydrator while changing the superheat setting
[单项选择]The needle valve in the injector （） at a pre-set pressure which ensures that the fuel will atomize once it enters the cylinder.
A. will lift
B. will be lifted
C. will close
D. will be closed
[单项选择]When start a screw pump, the by pass valve should be （）.
A. closed
B. opened fully
C. cracked open
D. partly open
[单项选择]When subjected to high heat from a open flame, or an electric heating element, which of the listed refrigerants will break down and produce phosgene gas?（）
A. CO2
B. Methyl chloride
C. R-22
D. Sulphur dioxide
[单项选择]When a hurricane passes into high latitudes over colder water and the source of heat is disrupted，the storm assumes the characteristics of（）.
A. a high pressure area
B. an extratropical cyclone
C. a tropical storm
D. an easterly wave
[单项选择]When working on a high voltage circuit, you should always have another person present with you.This person should have a good working knowledge of （）
A. the circuit being worked on and the location of all switches and circuit breakers controlling it
B. first-aid techniques for treating electrical shock
C. cardiopulmonary resuscitation (CPR)
D. All of the above
[单项选择]When navigating in high latitudes and using a chart based on a Lambert conformal projection，（）.
A. a straight line drawn on the chart approximates a great circle
B. the chart should not be used outside of the standard parallels
C. the course angle is measured at the mid-longitude of the track line
D. distance cannot be measured directly from the chart
[单项选择]When attempting to restart a warm high-speed engine, which of the following reactions can you expect?（）
A. Excessive fuel
B. Higher than normal temperatures for star up
C. Longer starting periods
D. Higher than normal lube oil pressure
[单项选择]When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates （）.
A. good insulation
B. bad insulation
C. high insulation power factor
D. a high slot discharge factor
[单项选择]When using a high-velocity fog stream in a passageway，the possibility of a blow back must be guarded against. Blow back is most likely to occur when（）.
A. pressure builds up in the nozzle which causes a surge of water
B. the only opening in a passageway is the one from which the nozzle is being advanced
C. pressure in the fire hose drops below 100 psi
D. a bulkhead collapses due to heat and pressure
[单项选择]When using a Lambert conformal chart in high latitudes，angles such as bearings are measured in reference to （）.
A. the meridian through the object of the bearing
B. the meridian through the ship's position
C. the meridian midway between the ship and the object
D. any meridian
[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
