单项选择题
An exhaust gas bypass is installed on a waste heat boiler in order to （）.
A.bypass exhaust gas at high loads to prevent excessive back pressure
B.bypass a portion of the exhaust gas at peak loads for better efficiency
C.recycle exhaust gas to the turbocharger
D.minimize moisture condensation in the boiler gas passages at low loads
相关考题
-
单项选择题
Which of the following actions should be taken if during a routine maintenance inspection of a centrifugal pump, localized scoring on a pump shaft sleeve is detected?（）
A.Correct the cause of the scoring and repair the sleeve or replace with a new one
B.Reassemble the unit and provide more water leak off for proper lubrication
C.Check for parallel alignment of the sleeve radial faces to the sleeve bores
D.Reassemble the unit and adjust the governor to obtain a slower speed -
单项选择题
Which of the materials listed is used as the dynamic seal material on mechanical seals installed on most centrifugal pumps used in water service?（）
A.Copper
B.Copper and carbon
C.Carbon
D.Bronze -
单项选择题
For the proper control of the air temperature in an air conditioning system using chilled water circulation, which of the listed conditions should remain constant regardless of load changes?（）
A.Chilled water system supply temperature
B.Chilled water system return temperature
C.Compressor discharge temperature
D.Compressor suction pressure
