Glossary of Terms
Alloy: Refers to material specification. For example, the aluminum standard alloy is 6063.
Band: A flat welded to a side or end of a grating panel, or along the line of a cutout, and extending neither above nor below the bearing bars.
Load carrying band: A band used to transfer the load between bearing bars.
Trim band: A band which carries no load, but is used chiefly to improve appearance and stability.
Bottom Bar/Shim Bar: A bar used to raise height of grating or wear plate.
Carriers: Flats or angles which are welded to the grating panel and nosing of a stair tread and are attached to a star stringer to support the tread.
Carrier Plates: Flat bars which are welded to each end of a piece of grating and nosing of a stair tread and are bolted or welded to a stair stringer to support the tread.
Close Mesh: Bearing bars spaced close together-Bearing bar center 11/16” or under.
Cross Bars: The connecting bars, made from a steel strip, slit sheet, rolled bars, of from rolled or extruded aluminum, which extend across the bearing bars, usually perpendicular to them. They may be bent into a corrugated or sinuous pattern and, where they intersect, the bearing bars are welded, forged, or mechanically locked to them.
Cross Bar Centers: The distance center-to-center of the cross bars.
Dove Tail: Pressure lock grating-aluminum or steel.
Electro-Forged: A process combining hydraulic pressure and heat fusion to forger bearing bars and cross bars into a panel grid (Forge-welded-Machine welded).
End Dimension (End Gauge): The distance from an end of grating to center of first cross bar.
Equal End Dimension: The same distance from the end of bar to center of the first cross rod on both ends of panel (except welded heavy duty, where distance is from edge to grating to back of first cross rod).
Filler Bar: The bar welded between 2 support bearing bars to close the spacing.
Finish: The coating, usually paint or galvanizing, which is applied to the grating.
Flat: Within tolerance of bow and crown-does not rock or bounce.
Flattening: A means of making bowed grating.
Floor Hole: An opening measuring less than 12” but more than 1” in its least dimension, in any floor or platform through which materials but not persons may fall; such as belt hole; pipe opening; or slot opening
Floor Opening: An opening measuring 12” or more, in any floor or platform through which materials may fall: such as hatchway, stair or ladder opening, pit, or large manhole. Floor openings occupied by elevators, dumb waiters, conveyors, machinery, or containers are excluded from this.
Flush Top Grating: A type of aluminum pressure-locked grating in which the cross bars and bearing bars are in the same plane relative to the top surface of the grating using the swaging process.
Grade: Refers to steel – Heavy duty is ASTM A36; Light Duty is ASTM A1011 CS Type B
Hinge: A device to create movable or swing grating (Piano Hinge – Butt Hinge – Heavy Duty Butt Hinge – Double Acting Hinge).
Hinged Panels: Grating panels which are hinged to their supports or to other grating parts.
Hollow Tube: Cross bar in Swage Lock Carbon Steel or Stainless-Steel grating –welded tube 5/16” diameter – .065” wall.
Intersection: The point where the bearing bar and cross bar intersect or cross. In heavy duty grating with a rectangular cross bar; an intersection has four (4) sides.
Length: The dimension of a grating panel measured parallel to the bearing bars.
Longitudinal: Refers to measurements along the span of the grating.
Mebac®: Type of surface, (not a finish). An applied gritted anti-skid surface.
Mebac® Strip: Abrasive strip with a Mebac® surface.
Nose: The portion of a tread projecting beyond the face of the riser immediately below. (OSHA definition)
Nosing: A special L-section member serving as the front or leading edge of a stair tread, or of grating at the head of a stair.
Nosing Angle Support: A steel angle welded to the front edge of a stair tread to support a removable nosing strip. The typical size is 1 ¼” x 1 ¼” 3/16”.
Nosing (ch’d plate): Angle nosing made of checkered plate whose typical dimension is 1 ¼” x 1 ¾”.
Nosing (Abrasive): Abrasive strip made of iron or aluminum that is attached to an angle made of means of nuts and bolts or TEK screws.
Nosing (Mebac®): Angle nosing with Mebac® surface.
Notched Bar: A cut out in the bearing bar. A burn out or punch.
Notched Grating: A fabricated corner cut out or small cut out.
Piece Mark: (Mark Number) Used to identify each unique piece.
Plate fastener: A 1” x 1” x 3/16” steel lug with a centrally located hole that is welded between the bearing bars at each corner of a piece of grating to hold the grating to its support.
Radially Cut Grating: Rectangular grating which is cut into pieces on one side only shaped as annular segments, for use in circular or annular areas. Skew cut is to have load carrying band.
Rip: Cut along the width of grating.
Seal Weld: Welding each bar on sides, top and bottom. Welded completely.
Serrated Grating: Grating which has the top surface of the bearing bars notched.
Skew Cut: A fabricated diagonal cut.
Span of grating: The distance between points of grating support, or the direction of the bearing bars.
Stop Angle: A piece of 1 ¼” x1 ¼” angle approx. 3” long that is centrally located and welded at each end and on the under side of a piece of grating. Its purpose is to prevent the grating from sliding off its supports prior to being fastened in place.
Stop bars: Steel lugs that are welded to the bearing bars of the 4 corners on the underside of a piece of grating at each of the 4 corners. Their purpose is to prevent 2 pieces of grating from meshing together or telescoping.
Swage locked: Grating manufactured by altering the cross sectional shape of a metal cross bar by applying pressure through dies.
T-bars: Steel lugs, which are the same depth as the bearing bars, that are welded between the bearing bars flush with the end of the grating at each of the 4 corners. Their purpose is to prevent 2 pieces of grating from meshing together or telescoping.
Toe Plate (kick Plate): Banding bar that protrudes above the top of the grating. Its purpose is to prevent items from being “kicked” off the edge of the platform. A 4” projection above the top of the grating is standard. Other projections can be provided when specified.
Tread run: The horizontal distance from the leading edge of a tread to the leading edge of an adjacent tread.
Tread Width: The horizontal distance from front to back of tread including nosing when used.
Transverse: Refers to measurements taken along the width of the grating.