Glossary
Key terms used in perforated metal, expanded metal, and bar grating manufacturing.
Perforation terminology
Essential dimensional parameters and hole arrangement standards used to specify perforated metal sheets.
Hole size
DimensionThe diameter or dimension of each perforation.
Measured in millimeters or fractions of an inch for round, square, or slotted openings.
Pitch
SpacingThe center-to-center distance between adjacent holes.
Determines the bridge/bar width between perforations and directly controls sheet rigidity.
Open area
RatioThe percentage of a sheet's surface that is open or perforated.
Crucial for calculating fluid flow, ventilation rates, light transmission, and acoustics.
Staggered pattern
LayoutHoles arranged in offset rows, typically 60° or 45°, maximizing open area.
The industry standard pattern offering the highest strength-to-weight ratio and open area.
Straight pattern
LayoutHoles arranged in aligned rows and columns.
Provides a clean, geometric visual profile with parallel alignment across length and width.
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