General Metal Mesh Terminology

Mesh Count: Refers to the number of openings per linear inch. Measured from the midpoint of a single wire to a 1-inch distance

Opening, Space or Aperture: Represents the clear space between two parallel wires. Commonly referred to as “space cloth”

Guage or Diameter: Refer to the thickness of individual round wires

Filter Rating or MERVs: A filter rating, or Minimum Efficiency Reporting Values, tells you whether wire mesh can effectively remove particles of a certain size from other matter. It is a measure of retention and is usually expressed in microns or percentages

Absolute Filter Rating: Mesh with an absolute filter rating has a retention approaching 100%

Calendering: A rolling process which flattens the knuckles of wire mesh giving it a smoother surface

Crimp: Corrugations in wires permit locking them in place when perpendicular to one another. Reduces deformation of hole size and shape

Open Area or Porosity: The proportion of open space in a total mesh area expressed as a percent

Micron: 1/1000-millimeter, 0.00003937 inch. The unit of measure for particle retention of filter media. A function of mesh count, wire diameter and opening

Permeability: The ability of a wire mesh to allow gas or liquid to pass through it

Woven Mesh Terminology

Weave: This refers to the specific pattern of intersecting wires in woven mesh

Shute, Fill or Weft Wires: Wires running across the width of the mesh as a woven

Warp Wires: Foundation wires running the length of the mesh as woven

Plain Weave: The most common woven mesh pattern. The shute and warp wires alternate passing over, then underneath each other to create a standard grid

Plain Dutch Weave: The warp wires have a larger gauge than the shute wires. As such, this weave features fewer warp wires than shute wires but the pattern resembles that of a plain weave

Twill Weave: Each warp wire and shute wire pass over two and then under two successive wires

Twilled Dutch Weave: Plain Dutch weave with a twill pattern. The weft wires are smaller than the warp wires and each warp wire and shute wire pass over two and then under two successive wires

Selvage or Loop Edge: Finished edges running the length of the woven wire roll to prevent unraveling

Expanded Metal Terminology:

Strand: A single metal strip that forms the border of the diamond shaped opening

Strand Width: is the amount of material advanced for expanding

Thickness: the thickness of the finished expanded sheet

SWO (Short Way Opening): The measurement of the empty space between the two nearer corners of the created aperture

SWD (Short Way of Diamond): The measurement of the empty area plus the strand width between the two nearer corners of the aperture, or the full height of the diamond shape

LWO (Long Way Opening): The measurement of the empty space between the two far corners of the created aperture

LWD (Long Way of Diamond): The measurement of the empty area plus the strand width between the two far corners of the aperture, or the full height of the diamond shape