Question:
Which ONE or MORE among the following options CORRECTLY match(es) the type of defects with the corresponding metal working processes in which they are likely to occur?
Defect Code Defect Process Code Process P Centerburst 1 Deep drawing Q Earing 2 Rolling R Zipper cracks 3 Extrusion S Cold shut 4 Closed die forging 5 Casting
Which ONE or MORE among the following options CORRECTLY match(es) the type of defects with the corresponding metal working processes in which they are likely to occur?
| Defect Code | Defect | Process Code | Process |
|---|---|---|---|
| P | Centerburst | 1 | Deep drawing |
| Q | Earing | 2 | Rolling |
| R | Zipper cracks | 3 | Extrusion |
| S | Cold shut | 4 | Closed die forging |
| 5 | Casting |
Show Hint
Match each defect to the process where it typically forms; remember cold shut can occur in both forging and casting.
Updated On: Aug 3, 2026
- P-3; Q-1; R-2; S-4
- P-5; Q-2; R-3; S-4
- P-1; Q-2; R-4; S-5
- P-3; Q-1; R-2; S-5
Show Solution
Verified By Collegedunia
The Correct Option is A, D
Solution and Explanation
Step 1: Understand what each defect means:
Centerburst (P) is an internal crack that forms at the centre of a bar or wire when it is pulled through a die.
Earing (Q) is the wavy, uneven rim that forms at the top edge of a deep drawn cup because the sheet does not have the same strength in every direction.
Zipper cracks (R) are small tears that appear along the centre line of a rolled sheet when the rollers stretch the middle more than the edges.
Cold shut (S) happens when two fronts of metal touch each other but do not fuse properly, leaving a visible seam.
Step 2: Match each defect to the process where it is common:
Centerburst is a classic defect of extrusion and wire drawing, where the outer layer of the rod is compressed while the centre is pulled in tension, so P goes with 3.
Earing is tied directly to deep drawing of sheet metal cups, so Q goes with 1.
Zipper cracks form during rolling, when the strip is squeezed unevenly across its thickness, so R goes with 2.
Cold shut can occur in two different processes: in closed die forging, when metal folds over itself instead of filling the die properly, and in casting, when two streams of molten metal meet and solidify before mixing. So S can be matched with either 4 or 5.
Step 3: Check each option against this matching:
Option (A), P-3; Q-1; R-2; S-4, matches cold shut with closed die forging. This is correct.
Option (B), P-5; Q-2; R-3; S-4, puts centerburst with casting and earing with rolling, both wrong, so this option is incorrect.
Option (C), P-1; Q-2; R-4; S-5, puts centerburst with deep drawing, which is wrong, so this option is incorrect.
Option (D), P-3; Q-1; R-2; S-5, matches cold shut with casting. This is also correct, since cold shut can happen in casting too.
Final Answer:
Both (A) and (D) give a valid pairing for cold shut, one with forging and one with casting, while the other three pairs P-3, Q-1 and R-2 stay fixed in both. \[ \boxed{\text{(A) and (D)}} \]
Centerburst (P) is an internal crack that forms at the centre of a bar or wire when it is pulled through a die.
Earing (Q) is the wavy, uneven rim that forms at the top edge of a deep drawn cup because the sheet does not have the same strength in every direction.
Zipper cracks (R) are small tears that appear along the centre line of a rolled sheet when the rollers stretch the middle more than the edges.
Cold shut (S) happens when two fronts of metal touch each other but do not fuse properly, leaving a visible seam.
Step 2: Match each defect to the process where it is common:
Centerburst is a classic defect of extrusion and wire drawing, where the outer layer of the rod is compressed while the centre is pulled in tension, so P goes with 3.
Earing is tied directly to deep drawing of sheet metal cups, so Q goes with 1.
Zipper cracks form during rolling, when the strip is squeezed unevenly across its thickness, so R goes with 2.
Cold shut can occur in two different processes: in closed die forging, when metal folds over itself instead of filling the die properly, and in casting, when two streams of molten metal meet and solidify before mixing. So S can be matched with either 4 or 5.
Step 3: Check each option against this matching:
Option (A), P-3; Q-1; R-2; S-4, matches cold shut with closed die forging. This is correct.
Option (B), P-5; Q-2; R-3; S-4, puts centerburst with casting and earing with rolling, both wrong, so this option is incorrect.
Option (C), P-1; Q-2; R-4; S-5, puts centerburst with deep drawing, which is wrong, so this option is incorrect.
Option (D), P-3; Q-1; R-2; S-5, matches cold shut with casting. This is also correct, since cold shut can happen in casting too.
Final Answer:
Both (A) and (D) give a valid pairing for cold shut, one with forging and one with casting, while the other three pairs P-3, Q-1 and R-2 stay fixed in both. \[ \boxed{\text{(A) and (D)}} \]
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