greater noida institute of technology
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GREATER NOIDA INSTITUTE OF TECHNOLOGY
DEPARTMENT OF MECHANICAL ENGG.
SEMINAR PRESENTATION
ON
BOILER
(BABCOCK & WILCOX BOILER)
Submitted To: Submitted By:
Mr. Syed Qaiser Husain Raju singh
CONTENT
Introduction
Classification
Babcock & Wilcox Boiler
Construction Of B&W Boiler
Working
Features
Accessories
Advantages & Disadvantages
Applications
INTRODUCTION A water containing vessel in which
water is heated under pressure Transfer heat from a fuel source (oil,
gas, coal) into steam The steam or hot fluid circulates out of
the boiler for use in various process or heating appliances.
Classification
Fire tube & water tube boiler
Babcock & Wilcox boiler
The evaporative capacity of this boiler is high compared with
other boilers (20,000 to 40,000 kg/hr). The operating pressure
lies between 11.5 to 17.5 bar.
The draught loss is minimum compared with other boilers.
The defective tubes can be replaced easily.
The entire boiler rests over an iron structure, independent of
brick work, so that the boiler may expand or contract freely.
The brick walls which form the surroundings of the boiler are
only to enclose the furnace and the hot gases.
Construction of B&W boiler
Steam and water drum ( boiler shell )
Water tubes
Uptake header and down corner
Grate
Furnace
Baffles
Super heaters
Mud box
Inspection door
damper
Working of Babcock and Wilcox boiler
Coal is feed to grate through the fire door and is burnt.
Flow of flue gases
Water circulation
A damper is fitted as shown to regulate the flue gas outlet and hence the draught
features of Babcock and Wilcox Boiler
efficiency is higher defective tubes can be replaced easily components are accessible for inspection
even during the operation draught loss is minimum Steam generation capacity and operating
pressure are high The water tubes are kept inclined at an angle
of 10 to 15 degree to promote water circulation
Accessories
Safety valve
Water level indicators
Bottom blowdown valve
Continuous blowdown valve
Flash tank
Automatic blowdown/continuous heat recovery system
Low water cut off
Steam drum internals
Surface blowdown line
Circulating pump
Feed water check valve or clack valve
Chemical injection line
Desuperheater tubes or bundles
Hand holes
Advantages
Steam can be generated at very high pressures
Heating surface is more Steam can be raised more quickly maximum amount of heat is transferred to
water A good and rapid circulation of water can
be made it is easier to transport It is suitable for use in steam power plants
Disadvantages
It is less suitable for impure and sedimentary water, as a small deposit of scale may cause the overheating and bursting of tubes. Hence, water treatment is very essential for water tube boilers.
Maintenance cost is high. Failure in feed water supply even for a short
period is liable to make the boiler overheated. Hence the water level must be watched very carefully during operation of a water tube boiler.
Applications
Stationary Marine Railways Variety of process applications in industries Chemical processing divisions Pulp and Paper manufacturing plants Refining units
THE END