Data and technical information

Manufacturing process
Expanded metal is manufactured from metals (sheet or strip/coil). The material is cut transversely and simultaneously stretched lengthwise. The cut length determines the mesh length, which runs across the material. The maximum overall length per piece is determined by the stretch factor, which depends on the mesh shape and the web width.

Strech factor
Expanded metal is manufactured from metal sheets or coils.
The material is cut transversely and simultaneously stretched lengthwise.
The material is cut transversely and stretched lengthwise.
... Stretch Factor
For strip as pre-material:
Mesh width : twice the web width > SFb = b : 2c Sheet: Stretch Factor
For sheet as pre-material:
Value from sheet calculation x 0.9 (due to the necessary retaining edge) > SFt = SFb x 0.9
Materials and specific gravities (weight of 1 sq m with 1 mm thickness) kg/dm³

Steel sheet 8
Stainless steel 8
Brass 8.5
Aluminum 2.7
Copper 8.9
Nickel 8.85
Titanium 4.5
Lead 11.34
Silver 10.5
Zirconium 6.52

In principle, plastics could also be stretched. However, polyethylene, polypropylene, and PVC have the property of reverting to their original shape. The stretched material shrinks, and the resulting dimension is not permanently stable.

Materials and specific gravities (weight of 1 sq m with 1 mm thickness) kg/dm³ Material Standards
Unique material definitions are provided, for example, according to previous DIN standards (such as 17100 – 17155), material numbers, EU designations, or the currently valid EN standards (e.g., EN 10025, 10028, 10088, 10111).

Mesh Dimensions
The mesh length is measured from node to node. For long-bar meshes, it is measured from the center of the unstretched bar across the mesh to the next center. The mesh length depends on the blade shape and cannot be freely selected; the possible mesh lengths between 3 mm and 300 mm can be found in the brochure. The mesh width depends on the depth to which the blade cuts the material. It can also be manufactured in widths between 2 mm and 110 mm, deviating from the dimensions in the brochure.

Mesh Shapes
There is the standard mesh – 4-sided, rhombus-shaped – and the long-bar mesh – 6-sided hexagon. Meshes according to the former DIN 791 standard visually correspond to the standard mesh.

Hot-dip galvanizing or sendzimir-galvanized material
Hot-dip galvanizing is only practical for mesh lengths of 28 mm and 9 mm or greater, as well as material thicknesses of 1.5 mm or greater, because with smaller meshes, the excess zinc does not drip off cleanly enough and leaves a film or zinc lump on the material. For smaller meshes, we recommend pre-galvanized material (sendzimir-galvanized St 02 Z or DX51D+Z). The bar cut surface is then barely galvanized, because during cutting, only individual zinc particles are drawn around the cut edge by the knife. Furthermore, the material combination provides anodic protection. St 02 Z-expanded metal does not offer 100% rust protection, but this is often sufficient if it is subsequently treated (wet painting or powder coating).

Standard Dimensions
Sheets: Large format 1500 mm wide, Medium format 1250 mm wide, Small format 1000 mm wide. Strips (Coils): Widths 600, 800, 1000, 1250, 1500 mm. Intermediate dimensions (slit strips) are available upon request for corresponding quantities.

Opening Distance in Longbond Meshes
The vertical opening refers to the distance between the end of the upper strand and the beginning of the lower strand. The clear opening refers to the open front distance between two staves.

Light Transmission
The light transmission of a mesh can be calculated in two ways. The ratio of material to air is calculated using the expansion ratio. A ratio of 2.5 means 2.5 meters of expanded metal from 1 meter of material; This results in a light transmission of approximately 60%. The value can be calculated more precisely using the following formula, which establishes a ratio between a fictitious reference value with a web width of 0 and the stretched mesh. (l – 2c) x (b – 2c) : 2 = Light area Example: Mesh 2810/2015 Reference value: l x b : 2 > 28 x (10 : 2) = 140 mm² Light transmission of the mesh: ( 28 – 2 x 2) x {(10 – 2 x 2) : 2} = (28 – 4) x {(10 – 4) : 2} = 24 x (6 : 2) = 24 x 3 = 72 mm² The light transmission of this mesh is 72 : 140 x 100 = 51.43%

Flat rolling
Maximum sheet width for flat rolling: 1500 mm, Maximum material thickness for steel sheet: 3.0 mm, Maximum material thickness for aluminum: 5.0 mm, Stainless steel: on request

Bending
Maximum material thickness for steel and stainless steel: 2.5 mm
Maximum material thickness aluminum: 3.0 mm