What are the Boiler Mountings, Accessories and Auxiliaries??
Boiler Mountings are the items fitted in Boiler for feed water and steam supply, measurement, control and Safety of the Boilers.
Boiler Mountings are the essential safety devices fitted on a boiler as per the Indian Boiler Regulations (IBR) or Boiler rules. They ensure safe operation and protect the boiler from any incidents and accidents.
These are not optional add-ons, but mandatory safety devices prescribed by the Indian Boiler Regulations (IBR) and international standards. Without them, operating a boiler would be unsafe and illegal.
Common mountings used in all type of the Boilers are;
- Feed Check valve or Feed control valve
- Main steam stop valve
- Main steam Non-return valve
- Water Gauge glass and level transmitters
- Safety valves
- Pressure gauge and pressure transmitters
- Continuous blow down (CBD) and Intermittent Blow down (IBD) valves
- Air vent valves
- Boiler Man holes
- Fusible Plug
What are the functions of Boiler Mountings??
Functions of Boiler Mountings;
- Safety valves Protect the boiler from overpressure and accidents
- Provide operators with control over steam generation
- Ensure safe operation under varying working conditions
- Water level gauges and transmitters prevent explosions by controlling pressure, water level, and steam flow
- They help in efficient operation of the Boiler by monitoring and controlling working conditions.
- Prevents damage to tubes, drums, and pipelines due to unsafe pressure or water levels.
- IBD and CBD blow down valves help in maintaining Boiler water parameters and correct water level in drums.
Boiler mountings are the lifeline of boiler safety. They are not just fittings but crucial devices that safeguard operators, equipment, and processes. Understanding their functions is essential for boiler engineers, plant operators, and students preparing for competitive exams.
What are Boiler Axillaries?
Boiler Auxiliaries are supporting equipment and systemsthat help in the operation, maintenance, and control of the boiler and power plant as a whole. These help in supplying the fuel, air and water for generating steam. They do not directly generate steam but are essential for boiler operation.
Common Auxiliaries used in Boiler are;
- Boiler fans (ID fan, FD fan, SA fan and PA fan)
- Boiler feed pump
- Fuel feeding system (Coal feeder or Bagasse feeder)
- Soot blowers
- Ash Handling system
What are the functions Boiler Axillaries?
- Boiler auxiliaries Ensures complete burning of fuel with the right supply of air by ID, FD & SA fans
- Boiler fuel handling and fuel feeding system in storing, feeding, and burning different types of fuel (coal, oil, gas, biomass).
- Boiler Axillaries Maintains proper air flow and flue gas removal.
- Manages waste products and keeps the furnace clean
- Boiler Axillaries helps to Collect and dispose ash from furnace and flue gases through ash handling plant.
For plant engineers and operators, understanding auxiliaries is as important as knowing mountings and accessories. A well-maintained auxiliary system reduces fuel costs, prevents breakdowns, and ensures compliance with safety and environmental standards.
What are the Boiler Accessories?
These are the devices installed to improve efficiency, performance, and economy of the boiler. A boiler may operate without accessories, but with lower efficiency and higher fuel consumption.
Unlike boiler mountings (which are mandatory for safety), accessories are not compulsory but highly recommended because they save fuel, improve steam quality, and reduce operational costs.
What are the different types of Boiler Accessories used in Boilers?
- Super heater
- Economiser
- Air Preheater
- Attemperator
- Steam Traps
- Steam Separators
- Feed Injectors
What are the functions Boiler Auxillaries?
- In Economizers, feedwater will be heated by using waste heat from flue gases. This, saves fuel by reducing the temperature difference between feedwater and boiler water.
- Air Preheater (APH) preheats the combustion air before it enters the furnace, which Increases combustion efficiency and reduces fuel consumption.
- Super Heaters convert saturated steam into superheated (dry) steam, this reduces steam consumption of turbines and improves efficiency.
- Feed water pumps, Pump feedwater into the boiler drum at high pressure and maintains continuous water supply.
- Steam traps Removes condensate from steam lines without letting steam escape.
Boiler accessories may not be mandatory, but they play a crucial role in making boilers more fuel-efficient and reliable. By recovering waste heat, preheating air and water, and supplying superheated dry steam, accessories can save significant operational costs and extend equipment life.
What are the differences among Boiler Mountings, Auxiliaries and Accessories?
| Sl No. | Boiler Mountings | Boiler Auxiliaries | Boiler Accessories |
| 1 | Mountings are the Devices fitted on the boiler for its safe and reliable operation. | Boiler Auxiliaries are the Supporting equipment that helps in the smooth operation of the boiler system | These are the Devices attached to the boiler to improve efficiency and performance. |
| 2 | Boiler mountings Purpose is Safety, control, and direct operation of the boiler. | The purpose of the Boiler Auxiliaries is Fuel handling, draft creation, ash disposal, and pollution control. | The purpose of the Boiler Accessories is for Fuel economy, better steam quality, efficient heat utilization. |
| 3 | These are compulsory/mandatory as per Boiler rules | These are not compulsory/mandatory as per Boiler rules | These are not compulsory/mandatory as per Boiler rules |
| 4 | With Mountings Boiler cannot be run safely legally | Without Boiler Auxiliaries boiler operation difficult | Without accessories Boiler can be run but not efficiently leading to lower efficiency and more fuel consumption |
| 5 | Mountings take direct role in steam generation | Not related directly in steam generation | Directly related in steam generation |
| 6 | Boiler Mountings Prevent accidents & ensures safe working | These enable boiler in smooth, continuous operation | Boiler Accessories Reduces fuel cost, improves steam quality |
| 7 | Examples: Safety valve, water level indicator, pressure gauge etc | ID fans, FD fans, PA fans, SA fans, fuel feeding, fuel handling, ash handling system, chimney etc | Economizer, superheater, air preheater etc |
Final conclusion on Boiler Mountings, Accessories and Auxiliaries;
Mountingsare the safety guards of a boiler, Auxiliaries are thesupport systems for Boiler and Accessories are the Accessoriesare theefficiency boosters.
