Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
38 Cards in this Set
- Front
- Back
|
What is a fire tube boiler? |
Has straight tubes full of gas that’s surrounded by water and steam |
|
|
List the advantages of fire tube |
Can handle low quality water Simple design Holds more water More heat reserve Cheap Less maintenance |
|
|
List the disadvantages of fire tube |
Limited pressure(348 psi) Slow to start up |
|
|
How are fired tubes boiler fired? |
Both internally and externally |
|
|
What are the types of fire tube boilers? |
Locomotives Scott Firebox |
|
|
Describe locomotive boiler |
Boilers that used a lot stays for support Had no fans Produces steam at 350psi Was used on trains |
|
|
What are the 2 types of locomotive boiler |
Dry bottom: water leg extents down Wet bottom: water leg surrounds the furnace |
|
|
Why are locomotive boilers not used anymore? |
Hard to maintain Had poor water circulation Was unreliable |
|
|
Describe a firebox boiler |
Has 2 or 3 passages Is externally fired Has a chamber that’s full of fuel or gas that’s burned to boiling point |
|
|
Describe scotch boiler |
Internally fired Produces 1700kpa of steam pressure |
|
|
List the advantages of package type fire tube boiler |
Low cost Cheap to design Compact Efficient |
|
|
List the disadvantages of package type fire tube boiler |
Difficult to clean and inspect |
|
|
List the parts of a fire tube boiler |
Shell Furnace Tubes Tube sheets Burner Reversal chamber Manhole |
|
|
Which part of a fire tube boiler was only recently added and describe its purpose |
Reversal chamber: changes the direction of gas from first to second chamber |
|
|
Where does the first point of combustion take place? |
In the furnace |
|
|
What’s the purpose of the tube sheets? |
Seal both ends of the shell and provide placement for tubes |
|
|
What fuel source can be used for burner? |
Light fuel oil Methane gas |
|
|
What are the 3 types of tubes used in fire tubes |
Cylindrical Tubular Seamless |
|
|
Between cylindrical, tubular and seamless tubes, which is used for high pressure? |
Seamless tube |
|
|
Between cylindrical, tubular and seamless tubes, which is used for moderate pressure? |
Tubular tubes |
|
|
Between cylindrical, tubular and seamless tubes, which is used for extreme pressures? |
Cylindrical tubes |
|
|
What are the 3 things you can attach to tubes of fire tube boiler? |
Tube expanders Beading Seal weld Groove
|
|
|
How do tube expanders work? |
Made up of 3 rollers and as it rotates it creates a force to expand tube |
|
|
How do beading works? |
Makes contact with tube sheet and expands it to maintain its form under pressure |
|
|
How do seal welds work? |
Extends contact with tube sheet to create cooling and maintains form |
|
|
When are grooved used for on pipes? |
To handle high pressure service |
|
|
What’s the purpose of Insulation and Refractory? |
To prevent: Heatloss, metal failure and prevent workers getting burned |
|
|
What materials are used for insulation and where is it placed ? Why? |
Materials: fibreglass and wool Applied outside the boiler prevents heat loss |
|
|
true or false. insulation can substitute refractory |
False, it cannot because it doesn't handle high temperatures |
|
|
What is refractory? |
a high temperature resistant material |
|
|
what are forms of refractory? provide an example for each |
Solids--> bricks Castable refractory---> cement Plastic refractory--> putty Ceramic blanket |
|
|
Describe a vertical tubeless boiler |
has no firetubes simple shell fired from the top and hot water comes down |
|
|
List the components of vertical tubeless boiler |
Tank Retainer ring reversing chamber fins vertical tube fire ignitor tube coils |
|
|
what's the purpose of fins in the vertical tubeless boiler |
allow more heat transfer |
|
|
Why must all firetubes provide decent water circulation? |
prevent uneven expansion keep heating transfer surfaces cooled prevent sludge formation |
|
|
List the 2 methods of water circulation and which boiler it used for? |
Natural Convection--> steam boiler Forced Circulation --> hot water boiler |
|
|
between wetback and dryback firetube boiler which is more used? |
Wetback because no parts of it is exposed air saving more heat |
|
|
what type of boiler is the cleverbrooks boiler? |
Package firetube boiler |
