QUESTIONS AND SOLUTIONS RATED A+
✔✔The type of fuel gas with the lowest btu content is _____ ______ gas and it has
______ btus per cubic foot. - ✔✔Blast Furnace; 90 btu per cubic foot
✔✔Sewage gas contains about 2/3 methane and 1/3 carbon dioxide. The heating value
is about _____ btu per cubic foot. - ✔✔650
✔✔The momentum of the low pressure gas is used to draw the air required to complete
the combustion process in an _________ burner. - ✔✔Atmospheric burner
✔✔Atmospheric burners have _________ to ________ percent pre-mixing of natural
gas and air. - ✔✔30 % to 70%
✔✔Infared flame scanners use a ____________ __________ cell to detect the
presence of a flame. - ✔✔Lead Sulfide
✔✔Unlike an infared scanner; the ultraviolet scanner is not affected by light given off by
hot________________. - ✔✔Refractories
✔✔What is the circumference of a circle with a 6" diameter? - ✔✔c=dx3.14
✔✔How do you find the area of a circle? - ✔✔A=Dsqared X .7854
✔✔Diameter of circle - ✔✔D=2 X Radius
✔✔Name four types of corrosion - ✔✔1. fretting 2. galvanic 3. crevice 4. localized
✔✔degree F to degree C - ✔✔C=(F-32)/1.8
✔✔C to F formula - ✔✔F=(C X 1.8)+32
✔✔GPM formula - ✔✔GPM=VxDsquared/.4085
✔✔Capacity formula - ✔✔GPM=LANE/231
✔✔A steam pressure guage has a _____ to protect against the high _________ of the
steam. - ✔✔siphon - temperature
✔✔A cross or tee connection to the boiler drum used eclusivly for attaching a test
pressure guage is known as - ✔✔inspectors connection
,✔✔A ________thermometer uses two dissimilar metals that bend predictably with a
change in temp. - ✔✔BIMETALIC
✔✔Minimum size for the connection between the guage glass and the water column is
_______ - ✔✔1/2"
✔✔2 or more saftey valves are required on a boiler with a heating surface inexcess of
______square feet or electric imput of ________KW - ✔✔500 sq ft ; 500KW
✔✔Safetey valves on a superheater should be set _____than the safety valve on the
steam drum - ✔✔lower
✔✔Boiler stop valves over 2 inches in diameter should be ___ _______ ___ ______. -
✔✔OS&Y
✔✔When boiler pressure exceeds _____psi; two blowdown valves must be used; one
must be a slow opening valve - ✔✔100
✔✔Slow opening blowdown valves must complete ___turns between full open and full
shut. - ✔✔5
✔✔A COPES feedwater regulator is an example of a ________ ____________type
feedwater regulator. - ✔✔thermostatic mechanical
✔✔The feedwater control valve position is controlled by the _______ of the fluid as
caused by the temp changes caused by water level changes in the thermostatic tube -
✔✔PRESSURE
✔✔The 3 element feedwater regulator senses ________ _________ AND_________. -
✔✔steam flow - feedwater flow - and water level
✔✔The _______ ________uses boiler water to complete the electrical circuit -
✔✔submerged electrode
✔✔The submerged electrode does not have a __________ _______. - ✔✔mercury
switch
✔✔2 types of electric boilers - ✔✔RESISTANCE and ELECTRODE
✔✔Electric current flows through the water and converts electrical energy to heat
energy in the ________type boiler - ✔✔ELECTRODE
, ✔✔A high voltage steam electrode has voltage between _____ AND_________ -
✔✔2300 and 15000 Volts
✔✔A high voltage steam electrode boiler has ___ generating compartments; one for
each phase. - ✔✔3
✔✔The capacity of a safety valve on an electric boiler is __ lbs per KW or ___ btus per
hr per KW - ✔✔3.5 LBS - 3500btus per KW
✔✔An HTHW system has better temp control becauase it has a large _______
_______ ________. - ✔✔heat storage capacity
✔✔Downtherm thermal liquid systems use ________ _____________ at tubes to
prevent leaking - ✔✔welded joints
✔✔__________ ________ boilers recover heat in the exaust from a gas turbine to
produce usefull steam - ✔✔WASTE HEAT
✔✔When exaust gasses dont have enough energy to produce the final steam pressure
_______ ________ is used. - ✔✔SUPPLEMENTAL FIRING
✔✔A recovery steam generator converts steam energy to mechanical energy to
produce electricity in a ________ ________ plant. - ✔✔COMBINED CYCLE
✔✔___________ ___________Sell steam to local industrial plants and surplus electric
to local utilities - ✔✔COGENERATION PLANTS
✔✔Superheated steam is injected into a gas turbine to increase electrical output in the
______ _____________. - ✔✔CHENG CYCLE
✔✔Waste products from sugar cane are used in a BAGASSE plant. When dried it has a
heating value of ________ to _________ btus per lb - ✔✔8000 to 8700 btus per lb
✔✔Black Liquor boilers are known for - ✔✔STEAM GENERATION and production of
SODA ASH
✔✔For black liquor boilers to sustain combustion - ✔✔they must contain _______%
solids.
✔✔Three types of ATMOSPHRIC BED BOILERS - ✔✔1.) BUBBLING 2.) DEEP 3.)
CIRCULATING FLUIDIZED BED