Flashcards in Steam Boilers Deck (83)
Is Lancashire boiler stationary or movable ?
Where is Lancashire boiler used ?
Sugar mills and textile industry
Why should water reserve be high for Lancashire boiler be high ?
Large quantity of steam is needed
Is the Lancashire boiler internally or externally fired ?
How many passes does it have for flue gases ?
Why does Lancashire boiler have good steaming quality (allowing for the use of low quality coal) ?
Heats water from three sides
What is the shape of the main shell ?
What is the cylindrical shell mounted on ?
A brick structure
How many base flue gas lines are there ?
How many side flue gas lines are there ?
How many flue tubes does the main cylindrical shell have ?
Two flue tubes
Where are the flue gases generated ?
At the grate
How many grates are there ?
Each flue tube has one
In what manner is the grate supported by a bridge ?
So that ash and coal do not enter the tube
Where do the flue gases go ?
End of the tube and then down
What happens to the flue gases when they reach the front of the boiler ?
Get divided into two streams and pass through side flues
Where do the flue gases go after travelling through the side tubes ?
Expelled to atmosphere through chimney
What should be the water level in the boiler ?
Above the main flue tubes
How is the water heated ?
By the passage of outgoing flue gases
How is fuel combustion controlled ?
What do dampers do ?
They reduce the flow of air by partial closing of the passage of the chimney
How are the dampers controlled ?
By chain and pulley block from outside
Where are superheaters kept, when they are provided ?
End of main flue tubes
What the mountings on top of the Lancashire boiler ?
Manhole, safety valve, steam collecting pipe
What are the mountings in front of the Lancashire boiler ?
Pressure gauge and water level indicator
What are the mountings provided at the bottom of the Lancashire boiler ?
Blow off cock
Where is the fusible plug mounted ?
Top of each main flue tube, just above the grate
Why is the efficiency of Lancashire boiler high ?
Because of mountings like economizer, superheater, large heat transfer area
Why is the surface area for the burning of coal reduced ?
The furnaces are inside the flue tubes