For sheet metal design engineer position interviewer ask questions on sheet metal design and manufacturing. To crack sheet-metal design engineer interview a good understanding of basic fundamentals of sheetmetal design will be helpful.
In this article we will discuss common sheetmetal interview questions. You can also contribute your experience by writing interview questions in comment section. We will try to add those questions in this article as well.
What is the difference between sheet metal blanking, punching & piercing operation?
Blanking is a process in which the punch operation removes a final product from a larger piece of sheet metal.
Punching is a material removal process in which the punch operation removes material from a final piece of sheet metal.
Piercing is process in which punch operation cuts a hole / material by tearing operation from a final piece of sheet metal. Piercing is a blanking operation
What are the different operations done for the manufacturing of sheet metal parts?
Following are general steps in manufacturing of sheet metal parts
Flat pattern -> CNC Cutting Programming -> Cutting operations (CNC Punching, laser/water cutting) -> Deburring —–> Hardware assembly ( PEM Hardware, Weld Nut, Rivet hardware) -> Press Bending -> Joining operations (welding/riveting) -> Grinding -> Finish operations – > Packing
What is the difference in hot rolled & cold rolled steel sheets?
Process of hot rolling involves rolling steel at a temp above re-crystallisation temp. During the cooling process steel will shrink and the size and shape of the steel will be less predictable.
While cold rolling involves at a temp below re-crystallisation temp (at around room temp). So there is no chance of steel shrinkage.
What is the criteria for the selection of sheet metal material for any application?
Following considerations need to be taken while selecting sheet metal material:
- Corrosion Resistance
- Part Weight
- Required finish
- Joining process
- Part Cost
What are the commonly used sheet metal joining operations during sheet metal part manufacturing?
Permanent Sheet Metal Joint:
- Adhesive Bonding
Reusable Sheet Metal Joints:
- Metric Screws
- Self Cutting Screws
- Sheet metal tabs
Why some times punching is preferred over laser cutting for sheet metal parts cutting?
With laser cutting sheet metal forming operations (extruded hole, lance, cut and bend) are not feasible.
What is minimum hole that can be processed with sheet metal turret punching press?
Minimum diameter of hole that can be punched in sheet metal should be equal to sheet thickness.
What are different press bending machine operations that can be done on sheet metal parts?
- 90 degree bend
- Z bend
- Hem bend
- Tab Bend
What are the type of welding done on sheet metal parts ?
- TIG welding
- MIG Welding
- Gas Welding
- Spot welding, seam welding
What is neutral axis in sheet metal?
When metal is bent the top section is going to undergo compression and the bottom section will be stretched. The line where the transition from compression to stretching occurs is called the neutral axis.