更多"The boiler water alkalinity in a co"的相关试题:
[单项选择]Excessive alkalinity of the water in an auxiliary boiler can cause ().
A. caustic embrittlement of the boiler metal
B. acidic corrosion of the boiler metal
C. hard scale deposits on the boiler tubes
D. etching of the heat exchange surfaces
[单项选择]The water level showing in a boiler water gauge glass is usually () during working.
A. higher than the actual drum water level
B. equal to the actual drum water level
C. increasing due to steam condensation in the glass
D. lower than actual drum water level
[单项选择]The correct pH value of boiler water is achieved by continuous addition of a suitable () to the feed.
A. acid
B. alkali
C. salt
D. None of the above
[单项选择]Impurities from the boiler water surface can be removed through the ().
A. safety valve
B. blow down valve
C. scum valve
D. feed check valve
[单项选择]The boiler feed water check valves are located on the ()
A. feed pump suction line
B. hot well
C. shell of the feed heater
D. feed lines to the boiler
[单项选择]For proper operation, auxiliary boiler feed water must have which of the following characteristics?()
A. High oxygen concentration
B. Low pH
C. Proper alkalinity
D. All of the above
[单项选择]In a () boiler the water flows through the inside of the tubes while the hot gases pass around the outside.
A. water-tube
B. fire-tube
C. exhaust gas
D. none of the above
[单项选择]In an auxiliary boiler steam and water system, the highest pressure will be in the ().
A. steam stop valve
B. dry pipe
C. feedwater system
D. generating tubes
[单项选择]If an operating auxiliary boiler has a water pH reading of 7, you should ().
A. bottom blow the boiler
B. treat the water with caustic soda
C. treat the water with chemical scavengers
D. reduce the water alkalinity to recommended readings
[单项选择]When steam is being raised on a boiler, the water level will normally ().
A. drop as the boiler warms up
B. rise as the boiler warms up
C. remain unchanged until the boiler is hot enough
D. rise and fall with the steam demand
[单项选择]The water in an operating auxiliary boiler should be tested for alkalinity and chloride content each().
A. hour
B. day
C. week
D. month
[单项选择]When a boiler is operating, the water level in the gauge glass reads () when the boiler is shut down.
A. lower than
B. higher than
C. as much as
D. the same as
[单项选择]The water in an auxiliary boiler should be tested daily for ().
A. dissolved oxygen
B. chlorides
C. sludge
D. dissolved nitrogen
[单项选择]The water in an auxiliary boiler should be chemically tested daily for alkalinity and()
A. soap hardness
B. nitrog encontent
C. chloride content
D. dissolved CO2
[单项选择]Water level controllers of the boiler must be kept operable to protect external steam-using plant from water “()” danger.
A. carry off
B. carry down
C. carry on
D. carry over
[单项选择]In readying an auxiliary water-tube boiler for a routine hydrostatic test, which of the following procedures should be undertaken prior to filling the boiler with fresh water?()
A. The safety valve escape piping should be disconnected from the valve body and a blank inserted
B. The boiler vent valves should be opened
C. All handhole/manhole covers should be tightened up as much as possible to preclude any leaks
D. All of the above
[单项选择]The feed water to the boiler will comprise ().
A. condensate
B. a small amount of make-up feed
C. A and B
D. None of the above