Power of Aluminium

Design Guidelines To achieve a successful product design, some guidelines for extrusion design will be very helpful.. These guidelines will help the designer to achieve extrusions with better functionality and extrudability and by that also less production costs and better all-round economy.
Uniform Wall Thickness Uniform wall thickness within a section reduces the loading on the die and therefore minimises the risk of it being damaged. Big differences in wall thicknesses within a section should also be avoided in order to minimise differences in surface appearance after anodising. Uniform wall thickness is obtained by changing the shape of the extrusion and putting the material where it is most needed.
Rounded Shapes As a rule all corners should be rounded. Normal radi are 0.4 to 1.0 mm. If the design requires sharper edges and corners, a radius of 0.2 mm is the smallest that can be produced.
Symmetry With symmetrical extrusion designs, a balanced flow of material through the die is achieved at the same time as the load on the die is evenly distributed. The extrusion shape is more accurate at the same time as the risk for broken dies is significantly reduced.
Diameter of the Circumscribing Circle Always try to reduce the circle circumscribed around the extrusion. Apart from making it easier to press the extrusion, it also helps keep die and production costs down.
Simplify and Facilitate A change that has no effect on the functional appearance of the extrusion but which simplifies and facilitates production means lower production costs and better economics.
Fewer cavities cut costs
A move towards a hollow extrusion gives better dimensional control
Increased size can cut the weight and increase the rigidity
Heatsinks The design of the flanges increases the surface of the extrusion and thermal conductivity.
Decorative Lines Decorative lines in an extrusion can conceal irregularities as well as protect against damage during handling and fabrication.

Recommended minimum material thickness (mm) in relation to the circumscribing circle diameter.

— Alloy 6082 - - - Alloy 6060
1 = solid extrusion. 2 = hollow extrusion.

The recommended ratio between the gap depth (h) and the gap width (b) in solid extrusions.

Maximum ratio between the
gap height (h) and the gap
width (b) in solid extrusions

Gap width
b

-1
1-2
2-3
3-4
4-5
5-15
15-30
30-50
50-80
80-120
120-

Ratio
h:b

1.0
2.0
2.5
3.0
3.5
4.0
3.5
3.0
2.5
2.0
1.5

The recommended ratio surface – gap width.

Maximum ratio
surface-gap width

Gap width
b

2-3
3-5
5-50
50-80
80-120
120-

Surface ratio
A:b2

2.0
3.0
3.5
3.0
2.0
1.5

Height – width ratio for hollow extrusions.

Height-width ratio for hollow extrusions
max. 3 max. 5 max. 6	Ratio h:b

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