WireCloth Terminology according to ISO 9044

A LABELLING Aperture width w Wirediameter d Open screening area, A
o : The per-centage of the area of all the aper- tures in the total screening surface or the ratio of square of the nominal aperture width w and the square of the nominal pitch p (= w + d), round- ed to a full percentage value: Pitch p Partial lengths: Woven wire cloth shall be labelledwith the following informations: –The name and the trade-mark of themanufacturer–the material of the wire –the nominal aperture width w –the nominal wire diameter d –the type of weave, if not plain –the length and width of the roll orstrip, or the size and number of pieces–the weight (mass), if required.If the cloth roll consists of several rollpieces, the length of each piece shall be indicated.Woven wire cloth in strips or pieces shall be so labelled on the outer pack- ing.The length and weight of each rolled strip (coil) shall be specified subject to agreement. Cloth width: Strips and cut-to-size-pieces: For rolls and roll pieces,the width of the cloth shall not be less than the nominal width, but may be up to 2 % in excess. A wire cloth roll myconsist of a maximum of three roll pieces. The minimum length of a roll piece is 2.5 m. Warp: All wires running lengthwiseof the cloth as woven. is the distance between themiddle point of two adjacent wires or the sum of the aperture width w and the wire diameter d. is the diameter ofthe wire in the woven cloth. (The wire diameter may be altered slightly during the weaving process.) is the distancebetween two adjacent warp or weft wires, measured in the projected plane at the mid-positions. Roll lengths: A standard roll is 25 or30.5 m long, and half rolls are 12.5 m or 15 m long. The length of rolls may be + or - 10 %. The delivered length is the one invoiced. Forstrips, the width shall be specified. With orders of quantities of less than a standard roll, the length of individual strips may be reduced accordingly. For cut-to-size pieces, the sides, lengths, angles and radii shall be specified. Weft: All wires running across thecloth as woven.
o = 100.(w : p)
2 Type of weave is the way in whichthe warp and weft wires cross each other. Weight G of the steel wire clothscreen section in kg per m
2 The number of apertures per unit length n G = (12.7 .d
2 ) : p G =Mesh.d is the number of aper-tures which are counted in a row one behind the other for a given unit length. The unit length may be 1 cm, 1 dm, Inch or any other unit of length. (The number of apertures with a length of 24.5 mm is designated as “Mesh”.)Mesh =number of apertures perEnglish inch = 25.4 : pn/cm =number of apertures per cm=10 : pn/cm
2 2The actual value can be up to 3 %lower. The wire diameter can be calculated using the following equation:d =G.pd =2.G12.7 Mesh
wpd wp Material: It is up to the user to speci-fy the choice of material with respect to: a) the final application of the wirecloth (e.g. resistance to environ- mental corrosion, suitability for food products etc.)b) the further processing (e.g. suit-ability for shaping, welding and surface treatment).Materials should be designated inaccordance with appropriate stan- dards, or if none exists, according to commercial specifications.
2 =number of apertures per cm
2 = (10 : p)
2

Types of Apertures

Square Aperture Rectangular “Oblong” Rectangular “Broad” Zero Aperture “Filter Cloth” 2