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Ritesh Maheshwari

The document is a presentation about boiler instrumentation and control. It discusses the basic components and functions of boilers, including generating steam through heat transfer. It also describes different types of boiler mountings, accessories, and classifications such as fire tube versus water tube boilers. The presentation covers boiler control loop systems, including single element, two element, and three element control loops. It concludes with goals of boiler control and potential future uses of microcontrollers and programmable logic controllers.

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Presented By:- RITESH MAHESHWARI 4th Yr, EIC. GIT, JAIPUR. Presented By:- RITESH MAHESHWARI 4th Yr, EIC. GIT, JAIPUR. Welcome to Presentation on Boiler instrUmentation & control Welcome to Presentation on Boiler instrUmentation & control 1GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
introdUction on Boilers introdUction on Boilers To generate steam at a desired pressure and temperature by transferring heat to water to change it to steam, produced by burning fuel . Inputs are fuel, combustion air, atomizing air or steam & feed water. Outputs are steam, flue gas, blow down, radiation & soot blowing. It can be classified in various ways: - To generate steam at a desired pressure and temperature by transferring heat to water to change it to steam, produced by burning fuel . Inputs are fuel, combustion air, atomizing air or steam & feed water. Outputs are steam, flue gas, blow down, radiation & soot blowing. It can be classified in various ways: - Tube contentsTube contents a). Fire tube b). Water tube a). Fire tube b). Water tube Method of firingMethod of firing a). Internally b). Externally a). Internally b). Externally Pressure of steamPressure of steam a). Low pressure b).High pressure a). Low pressure b).High pressure Circulation of water Circulation of water a). Natural b). Forced a). Natural b). Forced 2GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
Boiler moUntings and accessories moUntings Two safety valves Two water level indicators Pressure gauge Steam stop valve Feed check valve Blow-off cock Man and mud holes accessories Air preheater Economizer Steam superheater Feed pump Injector 3GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
BLOCK DIAGRAM OF BOILER DRUM CONTROL 4GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
CONTROL LOOP SYSTEM 5GLOBAL INSTITUTE OF TECHNOLOGY For the generation of steam to be continuous, it follows that the control also should be continuous and the needed adjustments for air flow, fuel flow, water flow, etc., should be adjusted simultaneously. It contain several variables with interaction occurring among the control loops for fuel, combustion air, & feedwater. Control loops used for boilers may be of the pressure, temperature, liquid level type, or flow type. Major loops in boiler control are: 1) Combustion control 2) Feedwater control A typical control loop includes a controlled variable sensor, controlled variable transmitter, controller, automatic-manual control station, and final control element. Saturday, April 25, 2009
TYPICAL CONTROL LOOP 6GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
SINGLE ELEMENT CONTROL SYSTEM Utilizes just a level transmitter to maintain control of the boiler drum water level. Controls feed water flow based on drum level. Measures drum level and regulates feedwater flow to maintain that level. Used for small boilers having relatively high storage volumes and slow changing loads. Response is very slow. Saturday, April 25, 2009 7GLOBAL INSTITUTE OF TECHNOLOGY
TwO ELEMENT bOILER CONTROL LOOP Utilizes a level transmitter & the amount of steam flow from the boiler to maintain control of the boiler drum water level. Provides compensation for variable loads. Used in intermediate boilers as well as large boilers. Flow and level transmitters are summed by a computing relay and will be the set point for feedwater. Response is faster. Saturday, April 25, 2009 8GLOBAL INSTITUTE OF TECHNOLOGY
THREE ElEmEnT boilER ConTRol looP Utilizes a level transmitter, the amount of steam flow from the boiler and the amount of water into the boiler to maintain control of the boiler drum water level. Corrects the problems associated with a two element control system and provides the best method of compensating for variable loads. The level and steam flow signals are summed and used as an index or set point to the feedwater flow. The feedwater flow measurement provides corrective action for variation in feedwater pressure. Saturday, April 25, 2009 9GLOBAL INSTITUTE OF TECHNOLOGY
ClASSiFiCATion oF boilERS FIRE TUBE BOILERS Simple, compact and rugged in construction. Classified as vertical and horizontal tube boilers. Since the water volume is more, circulation will be poor. So they can't meet quickly the changes in steam demand. High pressures of steam are not possible. Maximum pressure can be attained is about 17.5kg/sq cm. The output of the boiler is also limited. eg. Cochran, Lancashire, Cornish, Locomotive boilers Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 10
ClASSiFiCATion oF boilERS WATER TUBE BOILERS Movement of water in the water tubes is high, so rate of heat transfer also becomes high resulting in greater efficiency. Produce high pressure. Easily accessible and can respond quickly to changes in steam demand. Less weight and less liable to explosion. Attain pressure as high as 125 kg/sq cm and temperatures from 315 to 575 centigrade. Classified as vertical, horizontal and inclined tube depending on the arrangement of the tubes. Ex. Babcock and Wilcox boiler, Stirling boiler . Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 11
ConCluSionS Saturday, April 25, 2009 12GLOBAL INSTITUTE OF TECHNOLOGY The various goals of boiler control include: a) To minimize excess air. b) To minimize blow down. c) To minimize steam pressure. d) To measure efficiency. e) To find when to perform maintenance. In future, we can also use Microcontrollers & PLC as a controllers.
Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 13 To find fault is easy; to do better may be difficult -- Plutarch
Any questions? Please go ahead! Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 14

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ritesh

  • 1. Presented By:- RITESH MAHESHWARI 4th Yr, EIC. GIT, JAIPUR. Presented By:- RITESH MAHESHWARI 4th Yr, EIC. GIT, JAIPUR. Welcome to Presentation on Boiler instrUmentation & control Welcome to Presentation on Boiler instrUmentation & control 1GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
  • 2. introdUction on Boilers introdUction on Boilers To generate steam at a desired pressure and temperature by transferring heat to water to change it to steam, produced by burning fuel . Inputs are fuel, combustion air, atomizing air or steam & feed water. Outputs are steam, flue gas, blow down, radiation & soot blowing. It can be classified in various ways: - To generate steam at a desired pressure and temperature by transferring heat to water to change it to steam, produced by burning fuel . Inputs are fuel, combustion air, atomizing air or steam & feed water. Outputs are steam, flue gas, blow down, radiation & soot blowing. It can be classified in various ways: - Tube contentsTube contents a). Fire tube b). Water tube a). Fire tube b). Water tube Method of firingMethod of firing a). Internally b). Externally a). Internally b). Externally Pressure of steamPressure of steam a). Low pressure b).High pressure a). Low pressure b).High pressure Circulation of water Circulation of water a). Natural b). Forced a). Natural b). Forced 2GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
  • 3. Boiler moUntings and accessories moUntings Two safety valves Two water level indicators Pressure gauge Steam stop valve Feed check valve Blow-off cock Man and mud holes accessories Air preheater Economizer Steam superheater Feed pump Injector 3GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
  • 4. BLOCK DIAGRAM OF BOILER DRUM CONTROL 4GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
  • 5. CONTROL LOOP SYSTEM 5GLOBAL INSTITUTE OF TECHNOLOGY For the generation of steam to be continuous, it follows that the control also should be continuous and the needed adjustments for air flow, fuel flow, water flow, etc., should be adjusted simultaneously. It contain several variables with interaction occurring among the control loops for fuel, combustion air, & feedwater. Control loops used for boilers may be of the pressure, temperature, liquid level type, or flow type. Major loops in boiler control are: 1) Combustion control 2) Feedwater control A typical control loop includes a controlled variable sensor, controlled variable transmitter, controller, automatic-manual control station, and final control element. Saturday, April 25, 2009
  • 6. TYPICAL CONTROL LOOP 6GLOBAL INSTITUTE OF TECHNOLOGYSaturday, April 25, 2009
  • 7. SINGLE ELEMENT CONTROL SYSTEM Utilizes just a level transmitter to maintain control of the boiler drum water level. Controls feed water flow based on drum level. Measures drum level and regulates feedwater flow to maintain that level. Used for small boilers having relatively high storage volumes and slow changing loads. Response is very slow. Saturday, April 25, 2009 7GLOBAL INSTITUTE OF TECHNOLOGY
  • 8. TwO ELEMENT bOILER CONTROL LOOP Utilizes a level transmitter & the amount of steam flow from the boiler to maintain control of the boiler drum water level. Provides compensation for variable loads. Used in intermediate boilers as well as large boilers. Flow and level transmitters are summed by a computing relay and will be the set point for feedwater. Response is faster. Saturday, April 25, 2009 8GLOBAL INSTITUTE OF TECHNOLOGY
  • 9. THREE ElEmEnT boilER ConTRol looP Utilizes a level transmitter, the amount of steam flow from the boiler and the amount of water into the boiler to maintain control of the boiler drum water level. Corrects the problems associated with a two element control system and provides the best method of compensating for variable loads. The level and steam flow signals are summed and used as an index or set point to the feedwater flow. The feedwater flow measurement provides corrective action for variation in feedwater pressure. Saturday, April 25, 2009 9GLOBAL INSTITUTE OF TECHNOLOGY
  • 10. ClASSiFiCATion oF boilERS FIRE TUBE BOILERS Simple, compact and rugged in construction. Classified as vertical and horizontal tube boilers. Since the water volume is more, circulation will be poor. So they can't meet quickly the changes in steam demand. High pressures of steam are not possible. Maximum pressure can be attained is about 17.5kg/sq cm. The output of the boiler is also limited. eg. Cochran, Lancashire, Cornish, Locomotive boilers Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 10
  • 11. ClASSiFiCATion oF boilERS WATER TUBE BOILERS Movement of water in the water tubes is high, so rate of heat transfer also becomes high resulting in greater efficiency. Produce high pressure. Easily accessible and can respond quickly to changes in steam demand. Less weight and less liable to explosion. Attain pressure as high as 125 kg/sq cm and temperatures from 315 to 575 centigrade. Classified as vertical, horizontal and inclined tube depending on the arrangement of the tubes. Ex. Babcock and Wilcox boiler, Stirling boiler . Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 11
  • 12. ConCluSionS Saturday, April 25, 2009 12GLOBAL INSTITUTE OF TECHNOLOGY The various goals of boiler control include: a) To minimize excess air. b) To minimize blow down. c) To minimize steam pressure. d) To measure efficiency. e) To find when to perform maintenance. In future, we can also use Microcontrollers & PLC as a controllers.
  • 13. Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 13 To find fault is easy; to do better may be difficult -- Plutarch
  • 14. Any questions? Please go ahead! Saturday, April 25, 2009 GLOBAL INSTITUTE OF TECHNOLOGY 14