precipitate silica from solution
reduce corrosion in the heating coil
prevent clogging and erosion in the coil
maintain zero water hardness
第1题:
The water in an auxiliary boiler should be tested for chloride content to determine ( ).
A.total dissolved solids
B.salt contamination
C.water harcness
D.chlorine contamination
第2题:
If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause may be ______.
A.high steam pressure in the boiler
B.abnormally high feed-water temperature
C.abnormally high boiler water temperature
D.steam demand exceeding feed pump capacity
第3题:
The correct procedure for giving an auxiliary boiler a bottom blow, is to begin .
A.when the boiler has been secured long enough for most solids to settle
B.when the boiler has been cooled to ambient temperature
C.only after raising the water level to within 0.5 inch of the high water cutout only
D.after bypassing the low pressure
第4题:
relieve excess fuel oil pressure during the “off” fire cycle
admit water to the dry pipe
throttle the forced draft fan output for proper combustion
reduce excess steam pressure in the boiler
第5题:
concentrations of calcium sulfate in the boiler water
fuel oil in the feed water
improper treatment of the feed water with calcium sulfate
excessive feed water alkalinity
第6题:
what chemicals did you use to treat the boiler water ?when you test alkalinity and acidity of water in boiler by pH test paper ? the result shows the boiler water is in acidiity . please describe what the possible cause is .
第7题:
The boiler water alkalinity in a coil-type auxiliary boiler should be maintained at the pH recommended by the boiler manufacturer to______.
A.precipitate(使沉淀) silica (硅石)from solution
B.reduce corrosion in the heating coil
C.prevent clogging and erosion in the coil
D.maintain zero water hardness
第8题:
A.salinity is abnormally
B.high steam demand is too
C.feed-water flow is low
D.water level is abnormally low
第9题:
will be modulated in proportion
will be modulated in proportion and integral
will be modulated in proportion and differential
will not be modulated at all
第10题:
The safety valve escape piping should be disconnected from the valve body and a blank inserted
The boiler vent valves should be opened
All hand-hole/manhole covers should be tightened up as much as possible to preclude any leaks
All of the above