The function of a crosshead is to guide motion of the _________ and to prevent it from bending.
Piston rod
Connecting rod
Eccentric rod
Valve rod
Correct Answer :
A. Piston rod
Related Questions
Caking coals are those which
Form lumps or masses of coke
Burn freely
Show little or no fusing action
Burn completely
Which is not correct statement about effect of sulphur in fuel?
It has heating value
It helps in electrostatic precipitation of ash in flue gases
It leads to corrosion of air heaters, ducting, etc. if flue gas exit temperature is low
It erodes furnace walls
The number of water level indicators in a boiler are generally _________ in number.
One
Two
Three
Four
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
Which of the following statement is correct?
The efficiency of steam turbines is greater than steam engines
A flywheel is a must for steam turbine
The turbine blades do not change the direction of steam issuing from the nozzle
The pressure of steam, in reaction turbines, is increased in fixed blades as well as in moving blades
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 reheat factor depends upon
Initial pressure and superheat
Exit pressure
Turbine stage efficiency
All of these
When the cross-section of a nozzle increases continuously from entrance to exit, it is called a
Divergent nozzle
Convergent nozzle
Convergent-divergent nozzle
None of these
Locomotive boiler is a
Single tube, horizontal, internally fired and stationary boiler
Single tube, vertical, externally fired and stationary boiler
Multi-tubular, horizontal, internally fired and mobile boiler
Multi-tubular, horizontal, externally fired and stationary boiler
Which of the following boilers is best suited to meet fluctuating demands?
Babcock and Wilcox
Locomotive
Lancashire
Cochran
In a throttling process
Heat transfer takes place
Work is done by the expanding steam
Internal energy of steam changes
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 factor of evaporation for all boilers is always
Equal to unity
Less than unity
Greater than unity
None of these
The power of a boiler may be defined as
The ratio of heat actually used in producing the steam to the heat liberated in the furnace
The amount of water evaporated or steam produced in kg per kg of fuel burnt
The amount of water evaporated from and at 100° C into dry and saturated steam
The evaporation of 15.653 kg of water per hour from and at 100° C
A condenser where circulating water flows through tubes which are surrounded by steam, in known as
Surface condenser
Jet condenser
Barometric condenser
Evaporative condenser
The velocity of whirl at outlet for an axial discharge turbine is
Minimum
Maximum
Zero
None of these
The difference of supersaturated temperature and saturation temperature at that pressure is called
Degree of super-saturation
Degree of superheat
Degree of under-cooling
None of these
The diameter of Cornish boiler varies from
0.5 to 1 m
1 to 2 m
1.25 to 2.5 m
2 to 3 m
Which of the following statement is wrong?
Locomotive boiler is a water tube boiler
Water tube boilers are internally fired
Lamont boiler is a low pressure water tube boiler
All of the above
The critical pressure ratio for initially dry saturated steam is
0.546
0.577
0.582
0.601
The function of a safety valve is
To blow off steam when the pressure of steam inside the boiler exceeds the working pressure
To indicate the water level inside the boiler to an observer
To measure pressure of steam inside the steam boiler
None of the above
Gradually increasing temperature of flue gases at inlet to chimney for given steam outputs is an indication of
Higher effectiveness of boiler
High calorific value coal being burnt
Fouling of heat transfer surfaces
Raising of steam temperature
The diameter of internal flue tubes in a Lancashire boiler compared to its shell is
One-half
One-third
Two-fourth
Two-fifth
The object of producing draught in a boiler is
To provide an adequate supply of air for the fuel combustion
To exhaust the gases of combustion from the combustion chamber
To discharge the gases of combustion to the atmosphere through the chimney
All of the above
For the same length of stroke and speed of crankshaft, the piston speed for a double acting steam engine is _________ the piston speed of single acting steam engine.
Equal to
Twice
Three times
Four times
On Millier chart, the constant pressure lines
Diverge from left to right
Diverge from right to left
Are equally spaced throughout
First rise up and then fall
A single stage impulse turbine with a diameter of 1.2 m runs at 3000 r.p.m. If the blade speed ratio is 0.42, then the inlet velocity of steam will be
79 m/s
188 m/s
450 m/s
900 m/s
Fire tube boilers are those in which
Flue gases pass through tubes and water around it
Water passes through the tubes and flue gases around it
Forced circulation takes place
Tubes are laid vertically
Locomotive boiler is of the following type
Multi tubular
Horizontal
Internally fired
All of the above
Parson's turbine is a
Simple impulse turbine
Simple reaction turbine
Impulse-reaction turbine
None of these