Industrial Boilers-Thermodynamics-Lecture Slides, Slides of Thermodynamics

Download Industrial Boilers-Thermodynamics-Lecture Slides and more Slides Thermodynamics in PDF only on Docsity! Industrial Boilers  Steam generators  Closed vessels  made of steel and  used for generation of steam  vaporizing water  combustion of fuels  eg. coal,coke,oil,wood,saw dust and begesse etc.  Steam used for producing power,for industrial process work or for heating proposes. Docsity.com Requirements of a Perfect Steam Boilers  Should be absolutely reliable,capable of producing maximum steam at required pressure for minimum of fuel consumption,with minimum attention and minimum initial cost and operating cost.  Simple constructions  Quick starting from cold  Strong enough against temp. stress & strains  Well design combustion chamber  Less floor area, space & light weight  Best gauges,safety valves and other mountings  Easily accessible for inspection,cleaning and repairs Docsity.com Simple Cross tube vertical boiler  consists of a cylindrical shell surrounding a cylindrical fire box.  heating surface is about 8-10 times the grate area.  50% efficiency Docsity.com Cochran Boiler  It is well design of a Vertical multitubular fire tube boiler  Improvement over the simple vertical boiler as it provides greater heating surface.  Total heating surface area is about 10-25 times the grate area  Efficiency 70-75%  Ranges from 1m dia.X2m high,evaporation 20kg/hr to 3m dia X6m high,evaporation 3000kg/hr. Docsity.com 7 Cochran Boiler contd.... Docsity.com 4 Lancashire Boiler contd vecaes Gusset plaves . th. Side view of Lancashire Boiler, Docsity.com Locomotive Boiler  Is an internally fired multitubular fire tube boiler Docsity.com Babcock and Wilcox water tube Boiler  Water tube boiler having lager pressure ranges and larger sizes.  Three main parts, steam and water drum,water tubes and furnace. Docsity.com High Pressure Boilers contd………  La-Mont Boiler( Forced circulation Boiler) Docsity.com Once-Through Forced Circulation Boiler  Does not required a steam and water drum,saving in weight  Supercritical Pressure Boiler  Two types- Benson and Ramzin Docsity.com Ramzin Boiler ' | Compton steom ocd | rede, superheoter 7 Redehon stegm awoerkeater, Docsity.com Fire tubes Vs water tubes Boilers  Fire tubes boilers has a large volume of water,therefore more flexible and can meet the sudden demand of steam without much drop of pressure.  Fire tubes boiler is rigid and of simple mechanical construction,so greater reliability and low in first cost.  Fire tube boilers can be made in smallest sizes therefore simple to fabricate and transport, occupies less floor space but more height.  Due to mostly externally fired water tubes boiler so furnace can be altered considerably to meet the fuel requirements.  Water tubes boilers are more readily accessible for cleaning,inspection and repairs,compared to the fire tube boilers.  Modern trend is in the favors of water tube boiler due to continuous increase in capacities and steam pressures. Docsity.com Boiler Mountings and Accessories  Fitting and devices which are necessary for the safety and control are knows as boiler mountings  Fitting or devices which are provided to increase the efficiency of the boiler and help in the smooth working of the plant are knows as boiler accessories.  Fittings which are essential from the safety point of view are as follows,  Water level indicators  Safety valves  Combined high steam and low water safety valve  Fusible plug Docsity.com Boiler Mountings and Accessories contd….  Fittings which are essential from the control point of view are as follows,  Pressure gauge  Junction or stop valve  Feed check valve  Blow-off cock  Man hole and Mud Box  The important accessories are  Superheater  Economiser  Air-preheater  Feed pump or injector Docsity.com