Low Pressure Boiler Test A With
Complete Questions and Answers |
Updated 2025/2026
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.
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.
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.
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.
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
,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.
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
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.
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.
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.
What are pits, what causes them and how can you determine their depth. - ANSWERPits are small
hollow spots that could develop into holes. They are caused by oxidation.
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.
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.
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.
Complete Questions and Answers |
Updated 2025/2026
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.
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.
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.
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.
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
,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.
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
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.
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.
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.
What are pits, what causes them and how can you determine their depth. - ANSWERPits are small
hollow spots that could develop into holes. They are caused by oxidation.
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.
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.
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.
