Low Pressure Boiler Test A with
Complete Questions and Answers
Name 3 types of fire protection systems - ANSWER-Dry sprinkler system, dry chemical system,
halon system, inergen, FE-13, FM200, deluge, elecrronic alarm, wet charged.
When operating a pump under 200 f what kind of seals do you use? Will there be any leakage
and why? - ANSWER-Soft metallic packing or mechanical seals. Mechanical seals should not
leak, but with soft packing there will be minimal leakage to cool and lubricate the packing and
shaft.
Two types of centrifugal pumps and describe their differnces - ANSWER-In a volute pump the
impeller rotates in a casing of spiral design. The casing is designed to enclose the outer
extremity of the impeller. The volute chamber changes velocity head into pressure head.
In a turbine pump the impeller is surrounded by diffusion rings which take the place of the
spiraling casing in the volute pump. The quantity of water depends on the size of the impeller
and it's speed
How do you adjust the flow rate of a centrifugal pump? What would happen if the discharge
valve was closed on a centrifugal pump? - ANSWER-By throttling the discharge valve or by
changing the speed of the motor. Too much throttling may require the installation of a bypass.
If the valve is closed completely or throttled too much the pump is will slowly overheat.
What are the merits of the centrifugal pump? - ANSWER-Few moving parts, uniform flow, easy
to control, high capacities, dependable and long life.
Make a drawing of a centrifugal pump and explain how it works. - ANSWER-The spinning
impeller draws liquid into its center and discharges from its outer edge. Either a volute shaped
casing or the diffusion rings direct the liquid toward the discharge converting velocity energy to
pressure head.
Define perfect, complete and incomplete combustion - ANSWER-Perfect combustion l: burning
all the fuel using the theoretical amount of air
Complete combustion: burning all the fuel and using more than the theoretical amount of air.
,Incomplete combustion: when a portion of the fuel remains unburned because of insufficient
amounts of air.
Why is a row of tubes sometimes left out of an HRT boiler? - ANSWER-To improve circulation
which reduces carryover.
What are the essential steps in putting a cold boiler on line with other operating boilers? -
ANSWER-Blowdown gauge glass and water column
Check operation of feedwater valves and pumps
Open the vent on the boiler drum
Start the burner on low manual fire.
Test the flame scanner
Test the low water cutoff
When boiler pressure starts to build close the vent
Open the equalizing line around the header valve to warm the header
Open header valve drain and non-return valve drain
When the header is hot open the header valve and close the drain.
When the boiler pressure is 80% of header pressure unscrew the hand wheel on the non-return
valve and close the drain
When boiler pressure equals header pressure put the controls in automatic
How do you mechanically clean the waterside of a boiler tubes and what precaution should be
taken? What test should be down after the cleaning? How are boiler tubes cleaned other than
with mechanical means? - ANSWER-When cleaning fire tubes a knocker raps the inside of the
tube, cracking the scale off the outside. When cleaning water tubes a cutter head rotates inside,
cutting. And crushing the scale. Always keep the cutter head moving! A hydrostatic test should
be preformed after cleaning.
What are pits, what causes them and how can you determine their depth. - ANSWER-Pits are
small hollow spots that could develop into holes. They are caused by oxidation.
Make a plaster cast of the pit And surrounding plate. After the cast has set it will show the depth
of the pit.
Ultra/sound
Eddy current
, X-ray
What is a fyrite analyzer? Where is it used? Why is it used ? - ANSWER-It is a flue analyzer to
determine the amounts of CO2 and O2 in flue gases. Combustion gases are sampled from the
last pass or the breaching.
It determines combustion efficiency.
Describe a gate valve and where it is used most often - ANSWER-A valve with a wedge shaped
gate which is raised or Lowered into a passageway. The wedge shape tightens against the
sides when closed. Little resistance to flow when open. Used to isolate or shutoff flow.
How do you pipe a globe valve on a feed water system - ANSWER-
What is a pressure reducing valve ((PRV)) where is it used - ANSWER-The PRV automatically
reduces high pressure and maintains a lower delivery pressure. They are used for heating
systems, cookers, city water makeup, control air and gases or oil to a boiler.
Explain the letters SWP and WOG found on the side of a valve. - ANSWER-SWP is its
maximum steam working pressure
WOG is the maximum water, oil, gas pressure the valve may be used for.
What precautions should be taken be removing a manhole cover - ANSWER-Make sure the
boiler is vented and drained
What is scale and what causes it? Why is it bad for a boiler - ANSWER-Scale is a mineral sold
in boiler water being deposited in the heating surfaces. It is caused by high TDS (total dissolved
solids) and improper treatment of the boiler water. Scale forms An insulation layer that retards
the flow of heat to the water and cause the metal to become overheated.
Why are hot water systems more desirable than steam systems for heating blogs. Name two
types of hot water boiler heating systems. - ANSWER-Hot water heat is more consistent
because water retains its heat as it circulates and steam looses its heat rapidly as it condenses.
Two types are natural circulation and forced circulation
Complete Questions and Answers
Name 3 types of fire protection systems - ANSWER-Dry sprinkler system, dry chemical system,
halon system, inergen, FE-13, FM200, deluge, elecrronic alarm, wet charged.
When operating a pump under 200 f what kind of seals do you use? Will there be any leakage
and why? - ANSWER-Soft metallic packing or mechanical seals. Mechanical seals should not
leak, but with soft packing there will be minimal leakage to cool and lubricate the packing and
shaft.
Two types of centrifugal pumps and describe their differnces - ANSWER-In a volute pump the
impeller rotates in a casing of spiral design. The casing is designed to enclose the outer
extremity of the impeller. The volute chamber changes velocity head into pressure head.
In a turbine pump the impeller is surrounded by diffusion rings which take the place of the
spiraling casing in the volute pump. The quantity of water depends on the size of the impeller
and it's speed
How do you adjust the flow rate of a centrifugal pump? What would happen if the discharge
valve was closed on a centrifugal pump? - ANSWER-By throttling the discharge valve or by
changing the speed of the motor. Too much throttling may require the installation of a bypass.
If the valve is closed completely or throttled too much the pump is will slowly overheat.
What are the merits of the centrifugal pump? - ANSWER-Few moving parts, uniform flow, easy
to control, high capacities, dependable and long life.
Make a drawing of a centrifugal pump and explain how it works. - ANSWER-The spinning
impeller draws liquid into its center and discharges from its outer edge. Either a volute shaped
casing or the diffusion rings direct the liquid toward the discharge converting velocity energy to
pressure head.
Define perfect, complete and incomplete combustion - ANSWER-Perfect combustion l: burning
all the fuel using the theoretical amount of air
Complete combustion: burning all the fuel and using more than the theoretical amount of air.
,Incomplete combustion: when a portion of the fuel remains unburned because of insufficient
amounts of air.
Why is a row of tubes sometimes left out of an HRT boiler? - ANSWER-To improve circulation
which reduces carryover.
What are the essential steps in putting a cold boiler on line with other operating boilers? -
ANSWER-Blowdown gauge glass and water column
Check operation of feedwater valves and pumps
Open the vent on the boiler drum
Start the burner on low manual fire.
Test the flame scanner
Test the low water cutoff
When boiler pressure starts to build close the vent
Open the equalizing line around the header valve to warm the header
Open header valve drain and non-return valve drain
When the header is hot open the header valve and close the drain.
When the boiler pressure is 80% of header pressure unscrew the hand wheel on the non-return
valve and close the drain
When boiler pressure equals header pressure put the controls in automatic
How do you mechanically clean the waterside of a boiler tubes and what precaution should be
taken? What test should be down after the cleaning? How are boiler tubes cleaned other than
with mechanical means? - ANSWER-When cleaning fire tubes a knocker raps the inside of the
tube, cracking the scale off the outside. When cleaning water tubes a cutter head rotates inside,
cutting. And crushing the scale. Always keep the cutter head moving! A hydrostatic test should
be preformed after cleaning.
What are pits, what causes them and how can you determine their depth. - ANSWER-Pits are
small hollow spots that could develop into holes. They are caused by oxidation.
Make a plaster cast of the pit And surrounding plate. After the cast has set it will show the depth
of the pit.
Ultra/sound
Eddy current
, X-ray
What is a fyrite analyzer? Where is it used? Why is it used ? - ANSWER-It is a flue analyzer to
determine the amounts of CO2 and O2 in flue gases. Combustion gases are sampled from the
last pass or the breaching.
It determines combustion efficiency.
Describe a gate valve and where it is used most often - ANSWER-A valve with a wedge shaped
gate which is raised or Lowered into a passageway. The wedge shape tightens against the
sides when closed. Little resistance to flow when open. Used to isolate or shutoff flow.
How do you pipe a globe valve on a feed water system - ANSWER-
What is a pressure reducing valve ((PRV)) where is it used - ANSWER-The PRV automatically
reduces high pressure and maintains a lower delivery pressure. They are used for heating
systems, cookers, city water makeup, control air and gases or oil to a boiler.
Explain the letters SWP and WOG found on the side of a valve. - ANSWER-SWP is its
maximum steam working pressure
WOG is the maximum water, oil, gas pressure the valve may be used for.
What precautions should be taken be removing a manhole cover - ANSWER-Make sure the
boiler is vented and drained
What is scale and what causes it? Why is it bad for a boiler - ANSWER-Scale is a mineral sold
in boiler water being deposited in the heating surfaces. It is caused by high TDS (total dissolved
solids) and improper treatment of the boiler water. Scale forms An insulation layer that retards
the flow of heat to the water and cause the metal to become overheated.
Why are hot water systems more desirable than steam systems for heating blogs. Name two
types of hot water boiler heating systems. - ANSWER-Hot water heat is more consistent
because water retains its heat as it circulates and steam looses its heat rapidly as it condenses.
Two types are natural circulation and forced circulation
