Definitions & Formulae

Aperture (w)

Wire Diameter (d)

Mesh Count (n)

Pitch (p)

Warp

Weft

Open Area %

Porosity

Space between adjacent parallel wires, in mm.

(25.4 / n) – d

Diameter of wire before weaving, in mm.

Number of apertures per lineal inch measured from the centre of one wire to a point 1 inch (25.4 mm) distant.

25.4 / (w + d)

Distance between the centres of two adjacent wires in mm.

w + d or 25.4 / n

Wires running lengthwise in the cloth as woven.

Wires running crosswise in the cloth as woven.

The fractional open surface area of the wirecloth in the flow direction

(w²) / (w + d)² * 100 (applicable for square meshes only).

The fractional void volume of the mesh.