A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame
您可能感興趣的試卷
你可能感興趣的試題
A.low water level
B.low oil pressure
C.excessively high fuel pressure
D.an improper air/fuel ratio
A.Reciprocating pump
B.Screw pump
C.Diffuser pump
D.Water-ring pump
A.discharge is continuous
B.it has no internal valves
C.upon accidental closing of discharge valve, excessive pressure will not build up
D.all of the above are true
A.between the suction and discharge
B.below the liquid supply
C.above the liquid supply
D.any of the above
Which of the following pumps are self-priming, and can deal with liquid from a level below the pump? （）
(1) reciprocating
(2) vane
(3) gear
A.（1）only
B.（1）and（2）
C.（1），（2）and（3）
D.（2）and（3）
最新試題
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.
The general purpose of a heat exchanger is to （）.
If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
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 （）.
Thermostatic expansion valves can be adjusted for （）.
One cause of high head pressure occurring in a refrigeration system can be （）.
An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of （）.
Low compressor head pressure in a refrigeration system can be caused by（）.
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.