Expanded metal

Calculation of open area
SD / 2 x Strand = X
100 / X = Y
Y – 100 = % Open area

Mesh measurement
We currently have diamond and hexagonal shaped holes made from expanded metal which may be laminated (flat surfaced) or standard.

To define the diamond shape, we must identify the 4 parameters which form the mesh nomenclature.

• Short way diagonal (SD): distance between centres of two vertical rhombuses.
• Long way diagonal (LD): distance between centres of two horizontal rhombuses.
• Strand:  distance between one rhombus and the next rhombus.
• Thickness (T): sheet thickness.

Materials and measurements
The expanded metal may be made from different materials such as carbon steel, galvanised steel, aluminium, stainless steel, copper etc.

It can be made in rolls or sheets, the maximum width can vary depending on the thickness of the material.

The long way diagonal always has to be parallel to the material width.

Expanded metal uses the materials elasticity to conform its shape.

Flattened expanded metal
Expanded metal is, because of its manufacturing process, a non-flat surface. As the metal sheet is expanded it deforms and twists. The mesh can be flattened using a cold roll reducing mill; this will make strands and bonds to flatten, turning them into a smooth and flat surface. This process will also elongate the Long Way Diagonal (DL) and reduce the thickness of the mesh.

Dimension specification for flattened expanded metal.

Width:
Effective minimum = 300 mm
Effective maximum = 1.500 mm

Thickness:
Iron: 3 mm
Aluminium: 4 mm
Stainless steel: 2 mm