Coal Burner Nozzle & Tip

Coal Burner Nozzle and Tip Assembly are used to inject pulverized coal through the splitter plates tangentially from the four corners of a boiler. The fireball is kept in a turbulent and free mixing state to ensure optimum combustion. Through the tilting mechanism on the burner nozzle, the fireball is moved up and down inside the boiler furnace cavity to control the temperature of the steam leaving the boiler.

Coal burners are arranged in such a way that all mills Supply the coal to the burners at four corners of the furnace. All the nozzles of the burners are interlinked and can be tilted as a single unit from +30° to - 30°. The tips are attached to the nozzle body through hinges which allow tips to tilt about the axis. Firing is done using four burners corner to corner to create a fireball at the centre of the furnace and optimize combustion via control of near-burner time, temperature, turbulence, and stoichiometry.

The three main factors in determining efficiency are therefore flue-gas exit temperature, excess air and burnout, all of which are dependent on the Coal burner Nozzle & Tip. The flue-gas exit temperature is related to boiler design rather than the combustor. Accurate control of the amount of air is essential to boiler efficiency: Too much air will cool the furnace and carry away useful heat. Too little air and combustion will be incomplete, unburned fuel will be carried over and smoke may be produced.

The splitter plate assembly of the coal burner nozzle tip is subjected to severe pulverized coal erosion. The point at which the pulverized coal and primary air meets the steel components of the burner nozzle is the point of change of direction of flow and the point where the maximum erosion takes place.

• Inside surface of the Victaulic area of the coal nozzle body.
• The area of the coal nozzle body along the edge of the divider plate at the entry of the divider plate.
• The location of the divider plate at the entry of the Pulverized coal.

• Velocity Adopted for Fuel-Air Mixture: It has been learnt that the velocity adopted influences the wear rate on the coal burner. The higher the velocity, the higher the rate of wear, but this cannot be varied much as it depends on the burner requirement.
• The Pulverized Coal Fineness: Coal fineness has an influence on the rate of wear depending upon the segregation of ash from the organic portion of the coal.
• The geometry of the Burner/Coal Nozzle Tips: Burner /coal nozzle tip wear is a complex phenomenon. Amongst several factors affecting wear, burner/nozzle tip geometry plays a paramount role.
• Material (Alloys) for the Burner/Coal Nozzle Tips/ Splitter Plates: As burners are subjected to heat radiation from burning fuel, they are made of very high alloy steels. The more often preferred material is stainless steel 310 Grade.
• The Flame Profile and Distance from the Burner/Coal Nozzle Tip: The flame intensity and flame distance from the burner tip have two influences on the wear of the burner. One, it leads to warping of the burner tip and second, it creates eddies that accelerate wear.

We are a pioneer in bringing in the concept of “Repair Reclaim and Renew” critical and expensive components through our specially developed welding products and processes.

We have 6 decades of experience in maintenance and repair welding, with skilled manpower and experienced R&D support for innovation and improvements in providing Services. We also boast a 100% success rate.

For coal burner Nozzle and Tip our Proven Product, XHD AbraTec 6715 is an advanced electrode for hard facing a wide range of base material for abrasion/erosion at elevated temperature. The deposit consists of a complex Carbide system that retains Abrasion/erosion resistance up to 850°C with a Hardness of 62-68 HRc.

XHD AbraTec 6517 hardfacing layer retained on the Coal burner Nozzle and Tip which will maintain the hardness of 62-68 HRc at elevated temperature 850°C, due to its Abrasion /erosion and heat resistance property. This controls the air-fuel consumption, which promotes Boiler efficiency.