Terminology

Mesh Counts: The number of openings in a linear inch, counting from the center of any wire to a point 1 inch or 25.4 millimeters distant.

Wire Diameter: The measurement of the thickness of one wire.

Aperture / Opening: The dimension between two adjacent parallel wires, usually measured in inches or millimeters. Opening is not affected by diameter of the wire.

Micron: 1 micron is equal to 0.001 mm.

• The function of mesh count, wire diameter and aperture / opening.
• Mesh count = 25.4 mm / (wire diameter [mm] + opening [mm])

% Open Area: The proportion of the opening area in the total screen area expressed as a percent. See the following function.

• % Open Area = 100 * opening [mm]² / (opening [mm] + wire diameter [mm])²

Wires

• Warp Wires: The wires running across the length of the mesh as woven.
• Weft Wires: The wires running across the width of the mesh as woven. Weft wires are referred to as fill wires, shute wires, shoot wires.

Weaves

• Plain: Wire mesh in which each warp wire and each weft wire pass over one and then under the next adjacent wire in both directions.
• Twill: Wire mesh in which each warp wire and each weft wire pass over two and then under two successive wires.
• Plain Dutch: Weave style of wire mesh is the same as plain type; each warp wire and each weft wire pass over one and then under the next adjacent wire in both directions.
• The difference between them is the wire diameter. For plain type, the warp wires are the same as the weft wires. For plain dutch type, the warp wires are usually larger than the weft wires. The weft wires are closely spaced to provide a very tight weave.
• Twill Dutch: Similar with twill except the weft wires are smaller than the warp wires. Twill dutch weave is an even tighter weave and even finer filtration than plain dutch weave mesh.