In a Woolf type compound engine, the high pressure and low pressure cylinders
Have common piston rod
Are set at 90°
Have separate piston rod
Are set in V-arrangement
Correct Answer :
C. Have separate piston rod
Related Questions
A safety valve mainly used with locomotive and marine boilers is
Lever safety valve
Dead weight safety valve
High steam and low water safety valve
Spring loaded safety valve
The effect of super-saturation is that the
Mass of the steam discharged increases
Entropy and specific volume of the steam increases
Exit velocity of steam reduces
All of these
The draught produced by a steam jet issuing from a nozzle placed in the chimney is called
Induced steam jet draught
Chimney draught
Forced steam jet draught
None of these
Lancashire boiler is
Stationary fire tube boiler
Internally fired boiler
Horizontal boiler
All of these
The principal function of a stop valve is to
Control the flow of steam from the boiler to the main pipe and to shut off the steam completely when required
Empty the boiler when required and to discharge the mud, scale or sediments which are accumulated at the bottom of the boiler
Put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit
Increase the temperature of saturated steam without raising its pressure
The Parsons' reaction turbine has
Only moving blades
Only fixed blades
Identical fixed and moving blades
Fixed and moving blades of different shape
The shell of the Cochran boiler is made hemispherical
To give maximum space and strength
To withstand the pressure of steam inside the boiler
Both (A) and (B)
None of the above
A _________ in a boiler is used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit.
Blow off cock
Fusible plug
Stop valve
Safety valve
The average value of diagram factor lies between
0.2 to 0.5
0.5 to 0.65
0.65 to 0.9
0.8 to 1.2
Which of the following is a water tube boiler?
Lancashire boiler
Babcock and Wilcox boiler
Locomotive boiler
Cochran boiler
The critical pressure ratio is given by (where p₁ = Initial pressure of steam, and p₂ = Pressure of steam at throat or critical pressure)
p₁. p₂
p₁/p₂
p₂/p₁
p₁ + p₂
The maximum heat loss is a boiler occurs due to
Moisture in fuel
Dry flue gases
Steam formation
Unburnt carbon
In forced recirculation type boiler,
Heating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum
Water is supplied in drum and through down comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam
Feed pump is employed to supplement natural circulation in water wall type furnace
Water is converted into steam in one pass without any recirculation
The process of maintaining the speed of the turbine constant for various load conditions, is known as
Bleeding
Reheating
Governing
None of these
Lancashire boiler is used where working pressure and power required are
Low
Moderate
High
None of these
The velocity of steam leaving the nozzle (V) is given by (where K = Nozzle coefficient or nozzle efficiency, and hd = Enthalpy or heat drop during expansion of steam in a nozzle)
V = 44.72 hd K
V = 44.72 K hd
V = 44.72 K hd
V = 44.72 K hd
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
De-Laval turbine is a
Single rotor impulse turbine
Multi-rotor impulse turbine
Impulse reaction turbine
None of these
The discharge of steam in a convergent-divergent nozzle __________ after the throat (i.e. in the divergent portion of the nozzle)
Remains constant
Decreases
Increases
None of these
The best suited coal for chain or travelling grate stoker boiler is
Coking coal
Non-coking or free burning coal
Pulverised coal
High sulphur coal
The artificial draught is produced by
Steam jet
Centrifugal fan
Chimney
Both (A) and (B)
A steam nozzle converts
Heat energy of steam into kinetic energy
Kinetic energy into heat energy of steam
Heat energy of steam into potential energy
Potential energy into heat energy of steam
The saturation temperature of steam with increase in pressure increases
Linearly
Rapidly first and then slowly
Slowly first and then rapidly
Inversely
The difference between Cornish boiler and Lancashire boiler is that
Former is fire tube type and latter is water tube type boiler
Former is water tube type and latter is fire tube type
Former contains one fire tube and latter contains two fire tubes
None/of the above
Benson boiler requires
No drum
One drum
Two drums
Three drums
The flow through a nozzle is regarded as
Constant volume flow
Constant pressure flow
Isothermal flow
Isentropic flow
The diameter of internal flue tubes in a Lancashire boiler compared to its shell is
One-half
One-third
Two-fourth
Two-fifth
The ratio of total useful heat drop to the total isentropic heat drop, is called
Stage efficiency
Internal efficiency
Rankine efficiency
None of these
The safety valve at superheater as compared to drum safety valve setting is set at
Higher value
Lower value
Same value
Any value
The function of a piston in a steam engine is
To guide motion of the piston rod and to prevent it from bending
To transfer motion from the piston to the crosshead
To convert heat energy of the steam into mechanical work id) to exhaust steam from the cylinder at proper moment
None of these