网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
If the discharge valve is closed before the drive motor is stopped, which of the following types of pumps will most likely be damaged?（）
A
Centrifugal
B
Gear
C
Propeller
D
Turbine
参考答案
参考解析
解析：
暂无解析
更多 “单选题If the discharge valve is closed before the drive motor is stopped, which of the following types of pumps will most likely be damaged?（）A CentrifugalB GearC PropellerD Turbine” 相关考题
考题
To add refrigerant to the low side of an air conditioning system, the refrigerant should be introduced through the_______ .A.suction service valve as a vaporB.suction service valve as a liquidC.discharge service valve as a vaporD.charging valve as a liquid
考题
The valve on the discharge side of a cargo pump on a tank vessel will usually be a ______.A.butterfly valveB.spectacle valveC.check valveD.globe valve
考题
Before discharge of cargo tank ballast is undertaken，______．A.the deck isolating valve is openB.flue gas isolating valveC.blower suction valveD.blower discharge valve
考题
To ensure proper seating when closing a valve on a tank，the valve should be ______．A.Set up as tight as possible by handB.Set up tight using a valve wrenchC.Closed，opened a half turn，and then closedD.Closed against the stop and the locking pin inserted
考题
操作完后，关掉电动机。（）A、After operation, start the electric motor.B、Before operation, stop the electric motor.C、Before operation, start the electric motor.D、After operation, stop the electric motor.
考题
The security team has implemented new guidelines on how to handle sensitive information storedon workstations based on a past incident involving information found on donated workstations.Which of the following should be completed by technicians before donating the workstations?（）A、Install a new operating systemB、Delete users’ data before donationC、Write the drive with 1’s and 0’s three timesD、Delete all partitions of the hard drive
考题
单选题In （） pump a closed discharge valve will not cause excessive pressure to build up.A
gearB
vaneC
screwD
centrifugal
考题
单选题If the pump for a hydraulic anchor windlass is overheating, the cause may be （）.A
excessive drive motor speedB
excessive pump discharge pressureC
too low of a tilting box angleD
insufficient drive motor speed
考题
单选题Petroleum cargo tanks should not be topped off at deck level when loading on a cold day because（）.A
a subsequent temperature rise will cause the cargo to overflowB
air pockets may cause the cargo to bubble out of the ullage holeC
the increased viscosity of the product requires higher loading pressure which increases the chances of a spillD
the tank valve may be stiff and a spill will occur before the valve can be closed
考题
单选题If an electric motor driven air compressor fails to start, it may be due to a （）.A
leaking discharge valveB
jammed suction valveC
tripped overload relayD
broken discharge un-loader
考题
单选题If a centrifugal bilge pump were continually operated with the discharge valve closed the （）.A
motor overload would openB
relief valve would openC
pump would eventually overheatD
motor would overheat
考题
单选题What is a characteristic of all centrifugal cargo pumps? （）A
They are self-primingB
Decreasing the speed of rotation will decrease the discharge pressureC
Opening the discharge valve wider will increase the discharge pressureD
All of the above
考题
单选题In （） pumps a closed discharge valve will cause bursting discharge pressure.A
centrifugalB
plungerC
injectorD
water
考题
单选题Why is it important for fuel oil tanks not to be topped off at the inner bottom level when loading on a cold day?（）A
Increased viscosity of the product needs higher loading pressure, which increases the chances of a spillB
Air pockets may cause the fuel to bubble out of the ullage holeC
The temperature rise of the fuel will cause an overflowD
Fueling valve may become stuck closed and cause the fuel oil to spill before the valve can be opened
考题
单选题Which of the listed statements is correct concerning the starting of centrifugal pumps?（）A
They should always be started with the discharge valve closedB
They should always be started with the discharge valve openedC
A priming pump is always required to flood the impeller suctionD
They should always be started with the sealing line valves closed
考题
单选题A relief valve for a cargo pump is generally installed（）.A
after the discharge valveB
between the pump and discharge valveC
after the suction valveD
between the pump and suction valve
考题
单选题If a centrifugal pump were continually operated with the discharge valve closed, the （）.A
motor controller overload would openB
pump would eventually overheatC
relief valve would continuously cycle openD
motor would overheat
考题
单选题The valve on the discharge side of a cargo pump on a tanker will usually be a（）.A
butterfly valveB
spectacle valveC
check valveD
globe valve
考题
单选题One of the consequences in continuing to operate a centrifugal bilge pump with the discharge valve closed, is that the （）.A
motor overload will openB
relief valve will openC
pump will overheatD
motor will overheat
考题
单选题The simplest method to use for determining if a centrifugal pump is operating as designed, is to （）.A
closely observe the pump discharge temperatureB
close off the discharge valve, and watch for a rise in pressureC
momentarily close off the suction valve, and watch for a rise in pressureD
use a clamp on ammeter and compare the readings to past records
考题
单选题A centrifugal pump attempting to develop flow against a closed discharge valve has a/an （）.A
capacity of 0%B
efficiency of 100%C
internal slippage of 0%D
shut off horsepower rating of 100%
考题
单选题In a refrigeration system, which of the following statements describes the actions occurring when a solenoid valves, used in conjunction with an unloader head is energized?（）A
The solenoid valves directs high pressure gas to the valve lifting device raising the suction valve off its seat and causing one specific cylinder to become unloadedB
The solenoid valves directs high pressure gas to the underside of the unloading piston, causing it to rise and allowing the recirculating ports to be openedC
When the solenoid valve becomes energized, the valve ports become closed, allowing discharge pressure to build up above the piston, shifting it and causing it to unloadD
The solenoid valve allows the refrigerant to pass from the suction chamber to the top of the unloader piston, causing the piston to lift and unload the cylinder
考题
单选题The major difference between the discharge and suction valves installed in most low pressure, reciprocating air compressors is that（）A
one valve seats upwards, while the other seats downwardsB
the reed valves used on the discharge are made substantially thicker and heavier than the suction valvesC
the suction valve springs exert a greater tension than the discharge valve springsD
the discharge valve springs exert a greater tension than the suction valve springs
考题
单选题If the discharge valve is closed before the drive motor is stopped, which of the following types of pumps will most likely be damaged?（）A
CentrifugalB
GearC
PropellerD
Turbine
考题
单选题In slow speed two-stroke engines,（）the fresh air entering begins when and stops as（）A
the inlet port is opened by the up coming piston； the port is closed by the down goingB
the inlet valve is opened by the down going piston；the inlet valve is closedC
the inlet port is opened by the down going piston；the port is closed by the up comingD
the inlet valve is opened
考题
单选题The valve on the discharge side of a cargo pump on a tank vessel will usually be a（）.A
butterfly valveB
spectacle valveC
check valveD
globe valve
考题
单选题If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.A
a low load on the unitB
a clogged pump suction strainerC
a blockage in the line between the pump and hydraulic motorD
the hydraulic motor turning too fast
热门标签
最新试卷
