Section 5: Sheet Metalworking

Question 1

Categories of Sheet Metalworking

Answer 1

Performed on presses:
-Sheet metal cutting:
- Sheet metal shearing
- Sheet metal blanking
- Sheet metal punching
- Sheet metal bending:
- V-bending
- Edge bending
- Drawing
Not performed on presses
- Stretch forming
- Roll bending
- Roll forming
- Spinning

Question 2

Define Sheet Metalworking

Answer 2

Cutting and forming operations performed on relatively thin sheets of metal:
- Thickness of foil <= 0.4mm
- Thickness of sheet metal = 0.4mm-6mm
- Thickness of plate stock > 6mm

Question 3

Are Sheet metalworking operations usually hot or cold working

Answer 3

cold working

Question 4

What is the thickness of the foil for sheet metalworking

Answer 4

<= 0.4mm

Question 5

What is the thickness of sheet metal in sheet metalworking

Answer 5

0.4 mm - 6 mm

Question 6

Thickness of plate stock in sheet metalworking

Answer 6

> 6mm

Question 7

Advantages of Sheet Metal Parts

Answer 7

• High strength
• good dimensional accuracy
• good surface finish
• relatively low cost
• economical mass production for large quantities

Question 8

Punch and die

Answer 8

tooling to perform cutting, bending, and drawing

Question 9

Stamping press

Answer 9

Machine tool that performs most sheet metal operations

Question 10

Stampings

Answer 10

sheet metal products

Question 11

Sheet Metal Shearing

Answer 11

Category of sheet metal cutting to separate large sheets

Question 12

Sheet Metal Blanking

Answer 12

Category of sheet metal cutting to cut part perimeters of sheet metal

Question 13

Sheet Metal Punching

Answer 13

Category of sheet metal cutting to make punch holes in sheet metal

Question 14

Sheet Metal Bending

Answer 14

Straining Sheet around a straight axis

Question 15

Sheet Metal Drawing

Answer 15

Forming of sheet into convex or concave shapes

Question 16

Scrap and part in Blanking

Answer 16

• Blank is the part (interior of the cut)
• Strip is the scrap (exterior of cut)

Question 17

Scrap and part in punching

Answer 17

Part is the exterior
- Slug is the scrap (hole punched out)

Question 18

In sheet metal bending, what happens to the inside and outside of the neutral plane?

Answer 18

Metal on the inside of the plane is compressed, and the metal outside of the plane is stretch
Like turning the Letter I into the letter C

Question 19

V-bending

Answer 19

-performed with a V-shaped die
- low production (smaller Q)
- performed on a press brake
- v-dies are simple and inexpensive

Question 20

Edge Bending

Answer 20

• performed with a wiping die
• high production (Larger Q)
• pressure pad required
• Dies are more complicated and costly

Question 21

Sheet metal drawing process and products and other name

Answer 21

Process: sheet metal blank is positioned over a die cavity and then punched into opening
Products: cans, car body panels
AKA Deep Drawing

Question 22

Most press-working operations are performed with what tooling and why?

Answer 22

punch and die tooling
- Custom-designed for a particular part

Question 23

A name for high production dies

Answer 23

stamping die

Question 24

Sheet metalworking operations not performed on presses

Answer 24

• stretch forming
• roll bending and forming
• spinning

Question 25

Stretch forming

Answer 25

sheet metal is stretched and simultaneously bent to achieve shape change

Question 26

Roll Bending

Answer 26

Large metal sheets and plates are formed into curved sections using rolls

Question 27

Roll Forming

Answer 27

Continuous bending process in which opposing rolls produce long sections of formed shapes from coil or strip stock

Question 28

What is Spinning and its three types

Answer 28

Sheet metal forming process in which an axially symmetric part is gradually shaped over a rotating mandrel using a rounded tool or roller

Three types:
- Conventional spinning
- shear spinning
- tube spinning

Question 29

Conventional spinning vs Shear spinning

Answer 29

Conventional spinning leaves the thickness of the sheet metal unchanged. Shear spinning reduces it

Question 30

How does Conventional spinning work?

Answer 30

bends the metal around a moving circular axis to conform to the outside surface of the axisymmetric mandrel. The thickness of the metal therefore remains unchanged

Question 31

How does shear spinning work

Answer 31

outside diameter remains constant therefore wall thickness is reduced

Question 32

Tube Spinning

Answer 32

Tube spinning is used to reduce the wall thickness and increase the length of a tube by means of a roller applied to the work over a cylindrical mandrel.
Similar to shear spinning but in a tube rather than a flat disk