250+ TOP MCQs on Rod and Tube Drawing and Answers

Casting, Forming and Welding Multiple Choice Questions on “Rod and Tube Drawing”.

1. Which of the following types of stresses is applied during the process of rod or tube drawing?
a) Shear
b) Direct compressive
c) Tensile
d) In-direct compressive

Answer: c
Clarification: Rod or tube drawing is a deformation process in which the metallic material in the form of cylindrical bar is pulled by the help of a converging die. In general, the tensile stress is applied during the process. The strain hardening occurs which makes the material very hard and strong by reducing its ductility.

2. In rod drawing process, the cross-sectional area of the material remains constant.
a) True
b) False

Answer: b
Clarification: In rod drawing process, a bar or rod is drawn in order to reduce its diameter. The drawing operation results in the reduction in cross-sectional area of the material by increasing its length. This process is basically a kind of cold working process which takes place below the re-crystallization temperature of the material.

3. Which of the following processes of metal forming is widely used for making the raw material for the manufacturing of bolts?
a) Rolling
b) Forging
c) Wire drawing
d) Rod drawing

Answer: d
Clarification: Rod drawing is not completely similar to wire drawing process. Wire drawing is basically a metal forming process which is used for producing wires like electrical wires, cables, welding electrodes, fencing etc. And rod drawing is used for making the raw material for the manufacturing of bolts. The basic difference between rod drawing and wire drawing is the size of the metallic bar used for wire drawing is small.

4. Bar or rod drawing is a process which can be performed in a single draft.
a) True
b) False

Answer: a
Clarification: Bar or rod drawing process can be performed in single draft. A draft is a difference between the initial and final diameter of the metallic bar used. Whereas, for wire drawing process a small diameter metal bar is used. And wire drawing is basically done in multiple steps which use nearly around 4 to 12 dies.

5. In rod drawing process, the final output is coiled on a large metallic form roll.
a) True
b) False

Answer: b
Clarification: In rod drawing process, a draw bench is used instead of a form roll for drawing of rods or bars because rods cannot be coiled on any roll. The rod or bar is usually pointed by swaging operation and then fed into the drawing dies. And the tip of the rod is clamped into the jaws and then drawing process is carried out continuously.

6. Over drawing of the metallic rod can cause poor surface finish of the product.
a) True
b) False

Answer: a
Clarification: Rod drawing is a cold working process in which strain hardening occurs. Over drawing or reduction in cross-sectional area of bar beyond a certain limit can cause poor surface finish of the product. During this stage, the need of tensile stress increases substantially and the material becomes very hard and strong due to the reduction in its ductility.

7. In general, no any lubrication is required during the process of rod or bar drawing.
a) True
b) False

Answer: b
Clarification: In rod drawing process, the metallic rod is fixed into the dies by using a die holder and then a drawing head is used in which the metallic rod is fixed through a jaw mechanism. And then the bar is stretched and slides between the surfaces of the die, which causes friction and wearing. So to avoid such wearing, the rod is first lubricated before going into the process. In general, soap solution or oil is used for the lubrication in rod drawing process.

8. In rod drawing process, intermediate annealing is required for improving the ductility of material.
a) True
b) False

Answer: a
Clarification: Intermediate annealing is basically a kind of heat treatment process in which the material is heated and gradually cooled in order to obtain strength and ductility in the material. During the process of rod drawing, work hardening occurs which causes materials to be hard and less ductile, so for maintaining its mechanical properties, the intermediate annealing is performed.

9. Wet drawing is a process which involves throwing water jets onto the material during the process.
a) True
b) False

Answer: b
Clarification: Wet drawing basically involves dipping of metallic bar inside a lubricant bath before the next processing stage. In this process, the rod is lubricated by using lubricants like soap solution or oil. Lubrication can also be done by applying a coating of sulfate onto the material in order to retain the lubricant on the surface of metallic bar.

10. In rod drawing, a bearing is used which causes frictional drag on the metallic bar.
a) True
b) False

Answer: a
Clarification: In the rod or bar drawing process, the entrance of the die assembly includes a bell assembly which facilitates the entry of lubricant along with the metallic bar during the process. The bearing area causes frictional drag on the metallic bar and generally helps in the movement of the metallic bar inside the die mechanism.

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