Chapter No.2: Rolling and Forging Processes - Rolling Introduction Quiz
29 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the main purpose of metal forming processes?

  • To transform simple geometry into complex parts (correct)
  • To change the composition of the material
  • To increase the mass of the material
  • To simplify the geometry of the material
  • Which category do sheet metal forming operations fall under?

  • Powder metallurgy operations
  • Bulk forming operations
  • Casting operations
  • Sheet metal forming operations (correct)
  • How do rolls function in the rolling process?

  • By vibrating rapidly
  • By heating the material
  • By rotating to draw the work into the gap between them (correct)
  • By cooling the material
  • In the context of metal forming, what is rolling primarily used for?

    <p>Reducing the thickness of a slab or plate</p> Signup and view all the answers

    Which industry sectors benefit from items produced through metal forming processes?

    <p>Aeronautical and automotive industries</p> Signup and view all the answers

    What distinguishes metal forming processes from other manufacturing methods?

    <p>Transforming simple geometry into complex shapes without changing mass or composition</p> Signup and view all the answers

    What type of mill consists of upper and lower driven rolls and a middle roll that rotates by friction?

    <p>Three-high mill</p> Signup and view all the answers

    In a cluster mill, how many backing rolls support each of the work rolls?

    <p>Two backing rolls</p> Signup and view all the answers

    What is the purpose of feed rolls in a planetary mill operation?

    <p>To introduce the slab into the mill</p> Signup and view all the answers

    What is the main characteristic of a cluster mill compared to a four-high mill?

    <p>Each work roll being supported by two backing rolls</p> Signup and view all the answers

    What allows a planetary mill to hot reduce a slab directly to strip in one pass through the mill?

    <p>Pair of heavy backing rolls surrounded by planetary rolls</p> Signup and view all the answers

    What is synchronized in continuous rolling or tandem mills to maintain consistent speed throughout the process?

    <p>Input speed of each stand</p> Signup and view all the answers

    What is the angle subtended by the deformation zone at the center of the roll to achieve a 10% reduction in cross-sectional area of the strip after rolling?

    <p>6.84 degrees</p> Signup and view all the answers

    For a strip with a cross-section of 150 mm x 4.5 mm and being rolled with a 20% reduction of area using 450 mm diameter rolls, what is the angle subtended by the deformation zone at the roll center in radians?

    <p>0.02 radians</p> Signup and view all the answers

    In a rolling process where a sheet of 25 mm thickness is rolled to 20 mm thickness using a roll of diameter 600 mm rotating at 100 rpm, what will be the roll-strip contact length?

    <p>78 mm</p> Signup and view all the answers

    What factor leads to an increase in the maximum possible draft in cold rolling of a sheet?

    <p>Decrease in coefficient of friction</p> Signup and view all the answers

    How are seamless rings made in industry?

    <p>By a special rolling process called ring rolling</p> Signup and view all the answers

    In a rolling process, which pair of parameters directly affects the maximum possible draft (difference between initial and final thickness) of the metal sheet?

    <p>Strain, Strength of the work material</p> Signup and view all the answers

    What is the purpose of ring rolls in industrial processes?

    <p>Tube rolling and ring rolling</p> Signup and view all the answers

    How are threads typically formed using the thread rolling technique?

    <p>By axial flow of material in the workpiece</p> Signup and view all the answers

    What advantage do rolled threads have over cut threads?

    <p>Greater resistance to mechanical stress and increased fatigue strength</p> Signup and view all the answers

    What happens to the grain structure of the material when threads are rolled?

    <p>The grain structure is distorted to follow the thread form</p> Signup and view all the answers

    What is the entrance plane for a metal sheet entering the rolls in flat rolling analysis?

    <p>'xx' with a thickness 'h o'</p> Signup and view all the answers

    What is the general guideline for flash thickness in forging?

    <p>3% of the maximum thickness of the forging</p> Signup and view all the answers

    Why are draft angles necessary in almost all forging dies?

    <p>To facilitate removal of the part from the die</p> Signup and view all the answers

    Why are internal draft angles typically made larger than external ones in forgings?

    <p>To improve metal flow into the die cavity</p> Signup and view all the answers

    What is the adverse effect of small radii in forging?

    <p>Fatigue cracking of the dies</p> Signup and view all the answers

    Why should machining allowance be provided in forging-die design?

    <p>To achieve final desired dimensions and surface finish</p> Signup and view all the answers

    Where should machining allowance typically be provided in forging-die design?

    <p>At holes, at flanges, and at mating surfaces</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Browser