MANUFACTURING OF WROUGHT IRON

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• Q1: What is Wrought Iron?
  Ans: Wrought iron is a pure form of iron with very low carbon content.
  It is soft, ductile, and easily workable.
• Q2: State the uses of Wrought Iron.
  Ans: The uses are:

  • ➔ Chains and hooks
  • ➔ Pipes and tubes
  • ➔ Decorative items
  • ➔ Agricultural tools
• Q3: State the properties of Wrought Iron.
  Ans: The properties are:

  • ➔ High ductility
  • ➔ Good corrosion resistance
  • ➔ Tough and malleable
  • ➔ Low carbon content
  • ➔ Easily welded
• Q4: State the composition of Wrought Iron.
  Ans: The composition is:

  • ➔ Iron (Fe): about 99%
  • ➔ Carbon (C): less than 0.1%
  • ➔ Slag: small amount
• Q5: Briefly explain the manufacturing of Wrought Iron.
  Ans: Wrought iron is manufactured from pig iron using a puddling furnace.
  Impurities and excess carbon are removed by heating and stirring.
  The metal is then shaped into bars.
• Q6: What is a Puddling Furnace? What is it used for?
  Ans: A puddling furnace is a type of furnace used to convert pig iron into wrought iron.
  It removes carbon and impurities by heating and stirring the molten metal.
• Q7: What is a Reverbratory Furnace? What is it used for?
  Ans: A reverberatory furnace is a furnace where heat is reflected from the roof onto the material.
  It is used for heating metals without direct contact with fuel.
• Q8: What is a Single Puddling Furnace?
  Ans: A single puddling furnace has one working chamber where the metal is processed.
  It is used for small-scale production.
• Q9: What is a Double Puddling Furnace?
  Ans: A double puddling furnace has two working chambers.
  It increases production and efficiency.
• Q10: What are the Charges of Puddling Furnace?
  Ans: The charges of Puddling Furnace are as follows:

  • ➔ Pig Iron
  • ➔ Hot Air
  • ➔ Iron Oxide
• Q11: Briefly explain the Charging of Puddling Furnace.
  Ans: Charging is the process of adding pig iron and other materials into the furnace.
  The materials are heated until they become semi-molten.
• Q12: Briefly explain the Operation of Puddling Furnace.
  Ans: In operation, the molten iron is stirred continuously.
  Oxygen reacts with carbon and impurities to remove them.
  The metal becomes pasty and forms lumps.
• Q13: Briefly explain the Construction of Puddling Furnace.
  Ans: The puddling furnace consists of a hearth, firebox, chimney, and working door.
  Heat is reflected from the roof onto the metal in the hearth.
• Q14: What is the melting temperature of Pig Iron?
  Ans: The melting temperature of pig iron is about 1200^oC to 1500^oC.
• Q15: What are Puddlers Candles?
  Ans: Puddlers candles are bright flames formed during the burning of carbon in the furnace.
  They indicate the removal of impurities.
• Q16: What are Puddle Balls?
  Ans: Puddle balls are lumps of semi-solid iron formed during the puddling process.
  These are later worked into shapes.
• Q17: What is Squeezing or Shingling?
  Ans: Squeezing or shingling is the process of removing slag from puddle balls by hammering or pressing.
  It improves the quality of wrought iron.
• Q18: What are Merchant Bars?
  Ans: Merchant bars are finished wrought iron bars produced after rolling.
  They are used for commercial purposes.
• Q19: What is Ductility?
  Ans: Ductility is the property of a material to be drawn into thin wires without breaking.
• Q20: What is Purity?
  Ans: Purity is the degree to which a material is free from impurities.
• Q21: What is Fettling?
  Ans: Fettling is the process of repairing and preparing the furnace lining.
  It ensures proper working of the furnace.
• Q22: What is the purpose of Fettling?
  Ans: The purpose is:

  • ➔ To protect the furnace lining
  • ➔ To maintain proper working condition
  • ➔ To increase furnace life
• Q23: What is the Finery Process?
  Ans: Finery process is an old method of refining pig iron into wrought iron.
  It removes carbon by oxidation.
• Q24: What is the Bloomery Process?
  Ans: Bloomery process is an ancient method of producing iron from ore.
  It produces a spongy mass called bloom.
• Q25: Why is a puddling Furnace called a “Puddling” Furnace?
  Ans: It is called a puddling furnace because the molten metal is stirred (puddled) continuously.
  This helps in removing impurities and improving quality.