Preheating before welding is done to

A. Make the plate softer

B. Burn oil & grease sticking to plate surfaces

C. Avoid plate distortion

D. Prevent cold cracks

Please do not use chat terms. Example: avoid using "grt" instead of "great".

You can do it
  1. Ceramic compounds as compared to metallic compounds
  2. Limestone is added in the blast furnace (during pig iron manufacture) to
  3. The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________…
  4. Material of construction of the electrode used in the electric resistance welding is
  5. Holes for riveting purposes should be preferably made by
  6. Pick out the wrong statement.
  7. The dew point of moist air becomes __________ with decrease in its relative humidity.
  8. Use of water as a manometric liquid suffers from the disadvantage of its
  9. Shrinkage allowance on pattern is provided to compensate for shrinkage when the
  10. Use of flux during soldering is done to
  11. Hot extrusion process is not used for making
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  13. Yield strength of a material is determined by the __________ test.
  14. In extrusion of metals, which of the following statement is true?
  15. Speisses is a mixture of the following:
  16. Normalising does not __________ of a metal.
  17. Two solutions A1 & A2 have pH value of 2 & 6 respectively. It implies that the solution
  18. The approximate height of a blast furnace having a useful volume of 2000 m3 is about __________ metres
  19. Principal alloying element in Elinvar (used for making hair springs for watches) is
  20. The most important function of a washer is to provide bearing area and washers are normally specified…
  21. In fluid flow, and heat and mass transfer, one encounters (i) kinematic velocity (μ), (ii) molecular…
  22. The joint for soldering is supported by binding wire made of
  23. Which of the following is not the function of a volute casing provided in a centrifugal pump?
  24. Plastics as a material of construction suffer from the drawback of low
  25. Powder metallurgy is used to produce
  26. Larger length & diameter water pipes are made by
  27. Heat release during phase change is observed in case of a/an
  28. Which of the following is an acidic constituent of B.F. slag?
  29. A high pressure boiler generates steam at a pressure greater than __________ kg/cm2.
  30. For a small scale toy factory, the fixed cost per month is Rs. 5000/-. The variable cost per toy is…