Engineering Anatomy

Steel Grating Nomenclature & Components

Bar gratings consist of structural bearing bars fused or welded with transverse cross bars and framed by boundary bars to deliver optimal strength-to-weight performance.

Load Bearing Bars (Main Bars)

Bearing bars are the primary structural members positioned parallel to the span direction. They carry the applied loads and transfer forces directly to the supporting steelwork or concrete rebate.

Light Duty: 25 x 3 mm, 30 x 3 mm Medium Duty: 25 x 5 mm, 30 x 5 mm Heavy Duty: 40 x 5, 50 x 5, 65 x 5, 65 x 8 mm Extra Heavy Duty: 75 x 8, 75 x 10, 100 x 10, 120 x 10, 120 x 12 mm

Cross Bars (Transverse Connectors)

Cross bars are fused perpendicularly across bearing bars to maintain precise bar spacing and provide lateral restraint against torsional buckling under load.

Square Twisted: 6 mm, 8 mm Deformed Tore Steel: 8 mm, 10 mm Round & Hexagonal: 6 mm, 8 mm

Mesh Centers & Pitch Designations

Center-to-center (C/C) bar spacing is calibrated based on pedestrian ergonomics, wheel point loads, rolling resistance, and site ventilation requirements.

OM 30100: 30 mm pitch x 100 mm cross pitch OM 3050: 30 mm pitch x 50 mm cross pitch OM 40100: 40 mm pitch x 100 mm cross pitch OM 4050: 40 mm pitch x 50 mm cross pitch

Binding / Boundary Banding Bars

Flat bars perimeter-welded to closed panel ends. Boundary bars distribute local wheel loads across adjacent bearing bars and ensure safe handling during transit and installation.

Standard Boundary Sizes: 25 x 5 mm, 30 x 5 mm, 40 x 5 mm
Accredited Engineering Verification

Official V.J.T.I. Structural Type Test Certification

Empirical proof of load-bearing integrity verified by India's premier engineering institute, Veermata Jijabai Technological Institute (VJTI).

VJTI Government Certified

Independent Structural Load Testing Synopsis

To assure international EPC contractors, plant designers, and civil consultants of verified product safety, standard production grating panels underwent comprehensive hydrostatic and hydraulic type testing at the accredited testing laboratories of VJTI.

1500 × 1000 mm Tested Panel Geometry
30 × 5 mm Load Bearing Bar Cross Section
18 kN / m² Uniformly Distributed Load (UDL) Applied
Verified Test Outcome: Zero Structural Defects

Under maximum design proof loading of 18 kN/m² UDL, the test specimen exhibited complete elastic resilience with no visual cracks, no joint detachment at forged intersections, and no permanent plastic deformation, fully conforming to BS 4592, ANSI/NAAMM, and IS 2062 criteria.

Engineering Reference

Safe Working Load Tables & Clear Span Deflection

Theoretical safe uniformly distributed loads (U in kN/m²) and concentrated center line loads (C in kN) calculated at allowable bending stress fb = 165 N/mm² with maximum deflection limited to L/200 or 6 mm.

Bearing Bar Size (mm) Bar Pitch / Cross Pitch Weight (kg/m² approx) Span: 600 mm Span: 900 mm Span: 1200 mm Span: 1500 mm Span: 1800 mm VJTI Integrity Rating
25 × 3 OM 30100 (30/100) 19.8 U: 32.4 kN / C: 3.1 kN U: 14.4 kN / C: 2.1 kN U: 8.1 kN / C: 1.5 kN Pedestrian Only — Passed Safe
25 × 5 OM 30100 (30/100) 31.2 U: 54.0 kN / C: 5.2 kN U: 24.0 kN / C: 3.5 kN U: 13.5 kN / C: 2.6 kN U: 8.6 kN / C: 2.1 kN Pedestrian Only Passed Safe
30 × 3 OM 30100 (30/100) 23.5 U: 46.8 kN / C: 4.5 kN U: 20.8 kN / C: 3.0 kN U: 11.7 kN / C: 2.2 kN U: 7.5 kN / C: 1.8 kN — Passed Safe
30 × 5 OM 30100 (30/100) 37.1 U: 77.8 kN / C: 7.4 kN U: 34.6 kN / C: 5.0 kN U: 19.4 kN / C: 3.7 kN U: 18.0 kN / C: 3.0 kN U: 8.6 kN / C: 2.4 kN VJTI Certified
40 × 5 OM 30100 (30/100) 48.8 U: 138.2 kN / C: 13.2 kN U: 61.4 kN / C: 8.8 kN U: 34.5 kN / C: 6.6 kN U: 22.1 kN / C: 5.3 kN U: 15.3 kN / C: 4.4 kN Passed Safe
50 × 5 OM 30100 (30/100) 60.5 Heavy Rolling Loads U: 96.0 kN / C: 13.8 kN U: 54.0 kN / C: 10.3 kN U: 34.5 kN / C: 8.3 kN U: 24.0 kN / C: 6.9 kN Passed Safe
65 × 8 OM 4050 (40/50) 112.4 Extreme Vehicular U: 205.0 kN / C: 28.5 kN U: 115.3 kN / C: 21.4 kN U: 73.8 kN / C: 17.1 kN U: 51.2 kN / C: 14.2 kN Extra Heavy

* Note: Data above represents standard mild steel grades with yield strength FY = 250 N/mm². For stainless steel AISI 304/316, serrated surface bars, or dynamic impact conditions, engineering derating factors apply. Custom project calculations can be generated upon receipt of client drawings.

Manufacturing Governance

International Engineering Standards & Tolerances

Our design, fabrication, and surface treatments strictly adhere to worldwide regulatory benchmarks.

BS 4592 Part 1

Industrial flooring, walkways, and stair treads design standards for load bearing, open area requirements, and deflection safety parameters.

ANSI / NAAMM MBG 531

Metal Bar Grating Manual specifications covering physical tolerances, welded joint penetration, fabrication guidelines, and vehicular wheel loadings.

ASTM A123 / ISO 1461

Standard specifications for zinc (hot-dip galvanized) coatings on iron and steel products, guaranteeing uniform minimum coating thickness exceeding 85 μm.

IS 2062 / ASTM A36

Certified mill-test structural steel materials ensuring minimum tensile strength, chemical composition control, and ductility for fatigue resistance.

Require Specific Load Calculations or Custom Bar Sections?

Our engineering team can evaluate your exact support layouts, concentrated wheel loads, or corrosive operating parameters to issue certified fabrication drawings and price proposals.

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