License QUESTIONS WITH DETAILED
VERIFIED ANSWERS (100% CORRECT
ANSWERS) / ALREADY GRADED A+
how can you loose your license?✔✔1) drinking on the job
2) sleeping on the job
3) negligence
4) unsafe work
5) signing a falsified license application for someone
6) failing to renew your license annually
what must you do if you change jobs?✔✔notify city hall if you change jobs, address or retire
why should you do rounds?✔✔Find and correct problems to prevent breakdowns. keeping
permanent records will make it easy to forecast most breakdowns because you will get to know
equipment
what is a steam boiler?✔✔closed vessel, PARTIALLY FILLED WITH WATER, under pressure that
transforms water to steam with the application of heat.
what are the requirements of a good boiler?✔✔1) simple
2) designed to accommodate expansion and contraction
3) adequate steam and water space
4) efficient
5) responsive to demands
6) accessible for cleaning and repairs
7) safe
Name and describe 3 types of heat transfer used in boiler operation✔✔1) RADIANT HEAT -
transmitted from hot body to a cold body by means of direct radiation (heat from sun reaches us by
radiation)
,2) CONDUCTION - physical contact (coffee cup is heated by conduction when hot coffee touches the
cup)
3) CONVECTION - carried along by a moving part such as air or water (your living room is heated by
warm air from your furnace in another location
what is a combustion chamber?✔✔the area of the boiler where COMPLETE burning of the fuel
occurs
what is an internally fired boiler?
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name 4 types✔✔those in which the grate and combustion chamber are enclosed within the boiler
shell.
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1) Scotch marine
2) Vertical firetube
3) Locomotive
4) Cast iron package boiler
what is an externally fired boiler
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name 4 types✔✔the setting, including the furnace and grates is separate and distinct from the boiler
shell.
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1) horizontal return tubular (HRT) set in brick
2) some watertube
3) cast iron set in brick
4) Stirling boiler
5) Heine boiler
what is a crown sheet and its purpose?
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,what is a tube sheet and its purpose?✔✔in a vertical firetube boiler holds the tubes and is thicker
because it is exposed to the fire.
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holds the tubes and does not see the fire
what is a waterleg on a boiler?✔✔space between the outer shell and the furnace containing boiler
water. it absorbs heat that would be wasted and increases the capacity of the boiler. the surfaces
are flat and must be stayed.
is an HRT Boiler set level or inclined and why?
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are HRT Boiler tubes set level or inclined and why?✔✔INCLINED 1-3" front to rear to permit
drainage and removal of water impurities
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INCLINED with the boiler
Name 2 way to support and take care of expansion of an HRT Boiler
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Which way is best?✔✔1) Suspended from hangars and supported by overhead beams
2) Set on saddles equipped with rollers to permit movement of the boiler as it expands and contracts
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Suspended from hangars and supported by overhead beams is best because it works no hardship on
the furnace walls
what is a longitudinal joint?
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what is a circumferential joint?✔✔LONGITUDINAL JOINT = seam running the length of the shell and
is butt strap construction or fusion welded. it is above the fireline to avoid overheating.
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CIRCUMFERENTIAL JOINT = lap joint running the circumference of the drum
what is the difference between a flue and a tube?✔✔1) Flue - 4" or more in diameter measured
internally
, 2) Tube - 4" or less in diameter measured externally
what is a drypipe and where is it located?✔✔a steam separator located within the boiler shell and
connected to the steam outlet. its upper surface is perforated. steam enters the perforations rapidly
changing its direction of flow causing droplets and impurities to separate from the steam before
entering the steam outlet.
describe a Scotch Marine Boiler?
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how it is fired✔✔it is an internally fired self contained horizontal return firetube boiler.
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it is a cylindrical shell containing the combustion chamber and tubes that are surrounded by water.
how is a Stirling Boiler suspended?✔✔lugs on the ends of the upper drums rest on the beams of its
structure. the lower (MUD) drum is suspended from the tubes and is free to move by expansion.
describe the circulation of water within the Stirling Boiler✔✔feed water enters the top rear drum,
passes down the rear tubes to the mud drum. steam and boiler water go up the front and center
tubes to the front and center drums. CIRCULATING TUBES allow boiler water to pass between the
drums. what does not go out as steam, goes back down the rear tubes.
what provisions are made for tube removal on water boilers?✔✔1) some tubes are left out
2) the tubes are staggered
3) sometimes, every other row is omitted
What is a water tube boiler?
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list 5 advantages
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list 5 disadvantages
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name 4 types✔✔in a water tube boiler, products of combustion pass around tubes containing boiler
water