The cylindrical shell of a Lancashire boiler has diameter from
1 to 2 m
1.25 to 2.25 m
1.5 to 2.5 m
1.75 to 2.75 m
Correct Answer :
D. 1.75 to 2.75 m
Related Questions
Locomotive boiler is of the following type
Multi tubular
Horizontal
Internally fired
All of the above
Superheating of steam is done at
Constant volume
Constant temperature
Constant pressure
Constant entropy
Water and sediment in fuel oil can be removed by
Heating the oil in the settling tanks
Cooling the oil in the settling tanks
Burning the oil
Suspension
A device in which some portion of waste heat of flue gases is recovered to heat the air before it passes to the furnace for combustion purpose, is known as
Superheater
Air-preheater
Economiser
Injector
An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.
Equal
Less
More
None of these
The process of maintaining the speed of the turbine constant for various load conditions, is known as
Bleeding
Reheating
Governing
None of these
The ratio of the volume at cut-off to the swept volume is called
Cut-off ratio
Expansion ratio
Clearance ratio
None of these
If a steam sample is nearly in dry condition, then its dryness fraction can be most accurately determined by
Throttling calorimeter
Separating calorimeter
Combined separating and throttling calorimeter
Bucket calorimeter
Reheating of steam in a turbine
Increases the workdone through the turbine
Increases the efficiency of the turbine
Reduces wear on the blades
All of these
The safety valve on boiler drum compared to safety valve on superheater is set at
Same value
Higher value
Lower value
Lower/higher depending on steam flow
A turbine is said to have an axial discharge when the steam leaves the blade tip at _________ to the direction of the blade motion.
60°
90°
180°
270°
The density of supersaturated steam is about __________ that of the ordinary saturated vapour at the corresponding pressure.
Same as
2 times
4 times
8 times
The diameter of fire tube of Cornish boiler compared to its shell is
One half
One third
One fourth
One fifth
In order to compare the capacity of boilers, the feed water temperature and working pressure are taken as
50°C and normal atmospheric pressure
50°C and 1.1 bar pressure
100°C and normal atmospheric pressure
100°C and 1.1 bar pressure
During polytropic process
Heat transfer takes place across cylinder walls
Work is done
Steam may be wet, dry or superheated after expansion
All of the above
Which of the following are boiler accessories?
Economiser
Superheater
Both (A) and (B)
None of these
The relative heat absorption for successively added equal areas of boiler convection heating surfaces
Increases
Decreases
Remain unaffected
First increases and then decreases
The heat balance sheet for the boiler shows the
Complete account of heat supplied by 1 kg of dry fuel and the heat consumed
Moisture present in the fuel
Steam formed by combustion of hydrogen per kg of fuel
All of the above
Fire tube boilers are
Internally fired
Externally fired
Internally as well as externally fired
None of these
A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180° to each other, is called
Receiver type compound engine
Tandem type compound engine
Woolf type compound engine
Both (A) and (B)
Presence of moisture in fuel oil would
Keep the burner tips cool
Aid in proper combustion
Because sputtering, possibly extinguishing flame
Clean the nozzles
De-Laval turbine is a
Simple impulse turbine
Simple reaction turbine
Impulse-reaction turbine
None of these
Steam turbines are used for
Large marine propulsion
Electric power generation
Direct drive of fans, compressors, pumps
All of these
Willian's law states that the steam consumption per hour provided with a throttled governor is proportional to (where I.P. = Indicated power)
1/(I.P)
1/(I.P)²
I.P.
(I.P.)²
An economiser is installed in a boiler primarily to
Superheat the steam
Reduce fuel consumption
Increase steam pressure
All of these
When the back pressure of a nozzle is below the designed value of pressure at exit of nozzle, the nozzle is said to be
Choked
Under-damping
Over-damping
None of these
The diameter of internal flue tubes of a Lancashire boiler is about _________ that of its shell.
One-fourth
One-third
Two-fifth
One-half
Which of the following boilers is best suited to meet fluctuating demands?
Babcock and Wilcox
Locomotive
Lancashire
Cochran
The change in internal energy in steam engines equals to
Work done during the Rankine cycle
Work done during compression
Work done during adiabatic expansion
Change in enthalpy
During storage, the heating value of coal
Increases
Decreases
Remain constant
May increase or decrease depending upon the method of storage