Roll Forming MCQ

Test your knowledge with important Roll Forming MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Roll Forming MCQs at Bissoy

• What will be the theoretical elongation of outside fibre in ratio to the neutral axis, if inside bend radius is equal to the material thickness and the bending factor is equal to 0.33?
  ক

  14.5%

  খ

  25.3%

  গ

  40%

  ঘ

  50.3%
• It is difficult to form materials with high yield and ultimate tensile strength. Why?
  ক

  High ductility

  খ

  High fatigue strength

  গ

  Lower creep resistance

  ঘ

  Lower elongation
• Forming of any metal, however, must be achieved with stresses above the yield stress.
  ক

  True

  খ

  False
• Why blind corners and radii should be avoided while roll forming?
  ক

  It needs an additional setup

  খ

  It is time consuming

  গ

  Skilled labour is a need for that

  ঘ

  Less accuracy
• In roll forming, exact vertical side walls are avoided.
  ক

  True

  খ

  False
• Waviness at the edges can be avoided by_____
  ক

  longitudinal stiffening ribs

  খ

  incorporating a flange

  গ

  using roller support at the edges

  ঘ

  waviness can never be avoided
• The waviness can be seen in the formed product if unformed areas are less than _____ wide.
  ক

  100 mm

  খ

  120 mm

  গ

  125 mm

  ঘ

  150 mm
• Depth of roll formed section should be kept as small as possible.
  ক

  True

  খ

  False
• The parts shorter than_____ the centreline spacing of rolls of the machine employed will not feed or form satisfactorily.
  ক

  2 times

  খ

  3 times

  গ

  4 times

  ঘ

  5 times
• The minimum bend radius for bending material in roll forming is one stock thickness.
  ক

  True

  খ

  False
• When forming “Z” sections, the product is twisted in the opposite direction to compensate the machine generated twist.
  ক

  True

  খ

  False
• When an asymmetrical section is roll formed, the finished product will have _____
  ক

  Camber

  খ

  Cross-bow

  গ

  A twist

  ঘ

  Waviness
• What is camber in roll forming?
  ক

  Deviation of the strip edge from a straight line in horizontal plane

  খ

  Deviation of the strip edge from a straight line in vertical plane

  গ

  Difference in theoretical and actual elongation of the strip

  ঘ

  Waviness of the strip
• During roll forming, the strain (elongation) of the outside edge fiber of the strip must remain below the uniform engineering strain (elastic limit).
  ক

  True

  খ

  False
• What will be the elongation if a 1in high section is formed in four passes in a mill having a horizontal distance (between passes) of 14in?
  ক

  0.04%

  খ

  0.16%

  গ

  0.63%

  ঘ

  0.50%
• In case of “U” channel/ section, the length of travel of the edge of the strip (effective length of the strip) ‘s’, travelling in a helical pattern having initial length ‘l’ is given by_____
  ক

  l2 = s2 + c2

  খ

  c2 = l2 + s2

  গ

  s2 = l2 + c2

  ঘ

  s = l2 + c2
• What is “leg length” or “leg height”?
  ক

  The maximum vertical dimension of the profile

  খ

  Total length of the product

  গ

  Excess length of the product

  ঘ

  Maximum width of the section
• Which of the following is true in case of “too quick” forming (too few passes)?
  ক

  It makes the tooling and the process uneconomical

  খ

  It makes process easier

  গ

  It distorts the product

  ঘ

  Eliminate the need of a skilled operator
• Which of following is necessary in order to have a good set of rolls?
  ক

  Short horizontal distances

  খ

  Small lead-in flanges

  গ

  A smooth flow of material

  ঘ

  Less number of forming passes
• During roll forming, a flat strip is passed number of times through the rollers.
  ক

  True

  খ

  False
• Why additives are mixed with lubricating oil?
  ক

  To reduce the friction

  খ

  To increase the heat transfer

  গ

  To change the colour

  ঘ

  To improve the lubricant properties
• Macro-emulsions are also called as soluble oils.
  ক

  True

  খ

  False
• Which of the following is ideal for lubrication in roll forming of hot rolled and cold rolled steel?
  ক

  Micro-emulsion

  খ

  Macro-emulsion

  গ

  SAE 120

  ঘ

  SAE 20W 40
• For which of the following materials evaporative lubricants are used?
  ক

  Hot rolled steel

  খ

  Stainless steel

  গ

  Ferrous and non-ferrous materials

  ঘ

  Aluminium
• Which of the following is used for lubrication in heavy-duty roll forming?
  ক

  Extreme pressure-type solutions

  খ

  Soap-type solutions

  গ

  Non-ionic type solutions

  ঘ

  Micro-emulsions
• Chemical solutions (synthetics) ideal for coated steel.
  ক

  True

  খ

  False
• In how many types roll forming lubricants are categorised?
  ক

  3

  খ

  5

  গ

  6

  ঘ

  4
• Which of the following oils is used in roll forming equipment?
  ক

  SAE 140

  খ

  SAE 30

  গ

  Linseed oil

  ঘ

  SAE 5W-30
• EP 2 grease, high-temperature grease and chain and open-gear grease are used in roll forming equipment.
  ক

  True

  খ

  False
• Why spacers are used in roll forming machines?
  ক

  To prevent the springback of the material

  খ

  To fix the rolls in exact position

  গ

  To accommodate specific material thickness by adjusting the height

  ঘ

  To support the shaft