Sheet metal

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Sheets of stainless steel cover the Chrysler Building

Thin sheets of gold leaf

Sheet metal is simply metal formed into thin and flat pieces. It is one of the fundamental forms used in metalworking, and can be cut and bent into a variety of different shapes. Countless everyday objects are constructed of the material. Thicknesses can vary significantly, although extremely thin pieces of sheet metal would be considered to be foil or leaf, and pieces thicker than 1/4 inch or a centimeter can be considered plate.

[edit] Basics

Sheet metal is generally produced in sheets less than 6 mm. by reducing the thickness of a long work piece by compressive forces applied through a set of rolls. This process is known as rolling and began around 1500 AD. Sheet metals are available as flat pieces or as strip in coils. It is characterized by its thickness or gauge of the metal. The gauge of sheet metal ranges from 30 gauge to about 8 gauge. The higher the gauge, the thinner the metal is. There are many different metals that can be made into sheet metal. Aluminum, brass, copper, cold rolled steel, mild steel, tin, nickel and titanium are just a few examples of metal that can be made into sheet metal. Sheet metal has applications in car bodies, airplane wings, medical tables, roofs for building and many other things.

1 Basics
2 Processes

[edit] Processes

Forming metal on a bend press

A main feature of sheet metal is its ability to be formed and shaped by a variety of processes. Each process does something different to the metal giving it a different shape or size.

[edit] Stretching

Stretching is a process where sheet metal is clamped around its edges and stretched over a die or form block. This process is mainly used for the manufacture of aircraft wings, automotive door and window panels.

[edit] Drawing

Drawing forms sheet metal into cylindrical or box shaped parts by using a punch which presses the blank into a die cavity. Drawing process can also be utilised to create arbitrary shapes with the help of soft punch.

[edit] Deep Drawing

Deep Drawing is a type of Drawing process where the depth of the part is greater than its diameter. Deep drawing is used for making automotive fuel tanks, kitchen sinks, 2 piece aluminum cans, etc.

[edit] Cutting

Cutting sheet metal can be done various ways from hand tools called tin snips up to very large powered shears. With the advances in technology, sheet metal cutting has turned to computers for precise cutting.

[edit] Bending and Flanging

Bending and flanging imparts stiffness to a sheet metal part or to form various shapes, such as 3 piece aluminum cans[1]. See Bending (metalworking).

[edit] Punching and Shearing

During punching or shearing, the sheet metal is cut by using a punch and die.

[edit] Spinning

Spinning is used to make axis-symmetric parts by applying a work piece to a rotating mandrel with the help of rollers or rigid tools. Spinning is used to make rocket motor casings and missile nose cones for example.