ENGINEERING

STANDARDS
GLOSSARY / DEFINITION
Forge weld Steel Grating:
An open grid assembly of steel bars. Which has load bearing bars and cross bars jointing at intersection by forge welding at regular spacing.
Load Bearing Bar:
Load carrying bars, made from flat bar and extending in the direction of the grating span at regular spacing.
Cross Bar:
Load carrying bars, made from flat bar and extending in the direction of the grating span at regular spacing.

Load Bearing Bar Pitch:

Load carrying bars, made from flat bar and extending in the direction of the grating span at regular spacing.
Cross Bar Pitch:
The distance center to center of the Cross Bars.
Banding Bar:
A Flat welded to a side or end of a grating panel, or along the line of cutout, and extending neither above nor below the bearing bars.
Load Carrying Banding Bar: 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.
Span of Grating:
The distance between points of grating support, or dimension of the bearing bars in this direction.
Width of Grating:
The overall dimension of a grating panel, perpendicular to the bearing bars ( in line with the Cross Bar)
Toe Plate / Kickplate:
A Flat Bar attached flat against the outer edge of a grating to rear edge of a tread, and projecting above the top surface of grating or tread to form a lip or curb.
Serrated Grating:
Grating which has the top surfaces of the bearing bars notched.

Plain Grating:

Grating which has no notched at the top surfaces of the bearing bars.
Circular Cut Grating:
Rectangular grating which is cut into panels shaped as annular segments, for use in circular or annular are
Rectangular Cut Grating:
Common Rectangular grating for use in Rectangular Area.
TOLERANCE & QUANTITY MEASUREMENT
MANUFACTURING TOLERANCES
STANDARD INSTALLATION CLEARANCE
AREA CALCULATION / QUANTITY MEASUREMENTS
In accordance to ANSI/NAAMM MBG 531-00, Quantity Measurements for grating are calculated as follows:
1. Quantity Measurements for gratings ordered to specific dimensions without drawings, shall be based on span times width of each panel, with no deduction made for cutouts.
2. Final calculated grating quantities supplied based on drawings shall be on the bases of gross area measured center to center of supports, or back to back of supporting angles or channels, or overall dimensions of grating, whichever is larger, with no deduction for clearances. Allowances for cutouts shall be determined as follows:
a) Deductions in area for circular cutouts will be allowed only when the diameter of the cutout exceeds 1100 mm. The deduction allowance will be equal to 0.5 of the square of the diameter of the cutout.
b) Deductions in area for cutouts other than circular will be allowed only when the cutout area exceeds 1 m2.
c) No deductions will be allowed for any triangular segment or corners of gratings wasted in skew cuts.
d) For special applications, such as (but not limited to) containment areas in nuclear power plants, the final grating quantities shall be the total gross area of all the pieces furnished with no allowance for cutouts. See the following sketches:
PT. MULIA BERSAUDARA
Kawasan Industri Jababeka 1, Jl. Jababeka IIA Blok C11F, Cikarang, Bekasi – Indonesia
Phone : 62-21-8983 3902, Fax : 62-21-8983 3903,
email : mulia.bersaudara@mb-grating.com
website : www.mb-grating.com