A.pump must always be primed
B.volute must impart a radial and rotary motion of the water suction side
C.connection must guide the liquid to the lantern rings
D.stuffing box should not be allowed any water leakage
您可能感兴趣的试卷
你可能感兴趣的试题
A.change in impeller diameter
B.square of the impeller diameter
C.cube of the impeller diameter
D.impeller efficiency for large changes in the size of the impeller
A.the suction pressure to decrease
B.the suction temperature to increase
C.increased ice formation on the evaporator coil
D.excessive short cycling of the compressor
A.Lobe
B.Screw
C.Radial piston
D.Volute
A.They are particularly suited for pumping high viscosity fluids
B.They are started with the discharge valve opened
C.The flow of liquid is developed by imparting energy due to the rotation of an impeller
D.They are always mounted in a horizontal position
A.refrigerant pressure in the evaporator
B.cooling water temperature to the condenser
C.heat load in the refrigerator compartment
D.solenoid valve in the liquid line
A.compressor
B.condenser
C.expansion valve
D.evaporator
A.bimetallic type
B.diaphragm type
C.bourdon tube type
D.resistance-temperature type
A.evaporator coils
B.liquid strainer
C.compressor
D.condenser
A.suction side of a bilge pump
B.exhaust manifold of an auxiliary diesel
C.discharge line from an air compressor
D.chemical feed tank of an evaporator
A.They should always be started with the discharge valve closed
B.They should always be started with the discharge valve opened
C.A priming pump is always required to flood the impeller suction
D.They should always be started with the sealing line valves closed
最新试题
The temperature differential occurring between the inlet temperature of the fluid to be cooled and the outlet temperature of the cooling medium in a shell-and-tube heat exchanger is greatest in which of the flow designs listed?()
When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should ().
If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump ().
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by ().
An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of ().
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will ().
The control mode in which the final control element is moved from one of two flexed positions to the other is known as ().
Which of the listed pumps is NOT a positive displacement pump?()
The output volume of a positive fixed displacement pump can be changed only by ().
An excessive charge of refrigerant in an air-cooled refrigeration system can cause ().