Industrial Furnaces, Metallurgical Furnaces, Industrial Ovens, Industrial Driers, Industrial Ovens, Laboratory Furnaces, Solar Heating Systems, Energy Saving Gas Burners, Mumbai, India

FAQ

1 What are the various dependent variable for heat loss?

1. Temperature of product of combustion at entrance.

2. Time on air.

3. Temperature of the air.

4. Time on flue gas.

5. Thickness of checker bricks.

6. Specific heat of checker bricks.

7. Thermal conductivity of checker bricks.

8. Weight of checker bricks.

9. Arrangement of checker bricks.

10. Extent of heat-exchanging surface.

11. Velocity of flow of flue gas.

12. Velocity of flow of air.

13. Dust or flame content of the product of combustion.

14. Heat transmission coefficient from flue gas to bricks.

15. Heat transmission coefficient from bricks to air.

16. Heat transmitted in unit time.

17. Heat loss through enclosure.

2 What are the mode of the Heat transfer?

Heat gets transfered through the medium by means of conduction, convection and Radiation.

3 What are the variables that affect furnace capacity?

Following variables are affecting the furnace capacity

1.The temperature of the furnace wall when cold stock is charged.

2.Tempetature to which stock is to be heated.

3. Temperature of the product of combustion.

4. Emissivity of the product of combustion.

5. Emissivity of the wall.

6. Emissivity of the heat stock

7. Ratio of the wall surface to surface of the stock

8.Thickness of the layer of the product of combustion.

9. Thermal conductivity of stock.

10. Desired uniformity of temperature in the product.

11. Thickness of heat stock

12. Size of furnace

13. Velocity of gases in furnace

4 What are the different means of Heat loses in case on industrial furnaces and ovens?

1. Poor insulation.

2. Heat loss by the furnace gases escaping around the door.

3. Heat loss by radiation through openings.

4. Heat loss from furnace wall at Steady state (Steady state loss) and at the time of the operation (Intermediate state loss).

5. Heat loss due to part of the stock projecting out side of the furnace.

6. Loss due to conduction of heat through terminal or electrodes.

7. Heat imparted to water-cooled part.

8. Loss of heat to tongs and charging machines.

9. Loss to trays, conveyors chains and rollers.

5 How can we save the heat loss through the furnace or oven?

1. Reduction of wall losses, including storage loss.

2. Application of high-temperature heat to a low temperature charge without loss.

3. Preheating of the stock by waste heat.

6 What are the highest processing temperatures for the industrial processes?

Heating process or subsequent Operation	Highest temperature during heating process In degree C	Heating process or subsequent Operation	Highest temperature during heating process In degree C
Drying steel wire	150	Normalizing steel pipe	900
Drying lacquer	150	Colorizing	930
Japanning	80-230	Heating sheet bars	930
Core baking for iron casting	150-230	Normalizing sheet steel	950
Bluing	260	Carburizing	950
Hot dip tinning	260	Pack heating sheet steel	950
Temperature in oil	260	Short-cycle annealing, malleable iron	980
Tempering high speed steel	350	Cyaniding	980
Annealing aluminum	400	Glazing porcelain	1000
Cracking petroleum	400	Vitreous enameling ( Casting )	1010
Heating aluminum for rolling	455	Bar and pack heating , S.S.	1040
Nitrating steel	510	Normalizing stainless steel	930 - 1100
Annealing brass	540	Rolling stainless steel	960 - 1230
Annealing glass	620	Forging titanium alloy	870 - 1070
Annealing copper	620	Annealing manganese steel casting	1040
Annealing German silver	650	Heating tool steel for rolling	1040
Enameling, wet process	650	Heating sheet steel for pressing	1050
Strain relieving	650-705	Heating spring steel for rolling	1100
Annealing cold- rolled strip	677-760	Glost firing porcelain	1120
Porcelain decorating	760	Hardening high speed steel	1200
Heating brass for rolling	790	Bisque firing porcelain	1235
Annealing nickel	800	Rivet heating	1250
Annealing high carbon steel	820	Heating steel for die pressing	1300
Heat treating medium carbon steel	850	Calcining limestone	1380
Patenting wire	870	Welding steel tube	1400
Box- annealing steel sheets	870	Burning firebrick	1320-1450
Vitreous-enameling iron steel	870	Burning Portland cement	1430
Annealing malleable iron	870	Glass melting	1430
Heating copper for rolling	870	Steel melting	1670
Forging commercially pure titanium	870	Melting chromium steel	1790
Annealing steel castings	900

7 What are factors that affect strength and Durability of the furnace?

1. High temperature.

2. Variation of temperature.

3. Chemical effect of oxide, sulfur compound , and slags.

4. Oxygen and other gases or vapors at high temperature.

5. Explosions.

6. Mechanical injury by moving solids.

7. Steam and water.

8. Excessive loading on roofs and sidewalls.

9. Yielding of foundation.

10. Vibrations.