Product Overview
High Load Molded Grating is a heavy-duty fiberglass-reinforced plastic (FRP) structural grating engineered specifically for vehicular traffic and extreme concentrated loads.
Our high load molded grating is manufactured by precision molding of continuous E-glass fiber rovings in a thermoset polymer matrix. Related FRP solutions: pultruded FRP profiles, FRP rebar, pultrusion machines, and pultrusion dies.
Manufactured through precision molding of continuous E-glass fiber rovings within a thermoset polymer matrix, this bi-directional grating system delivers high load capacity at about 25% the weight of steel grating for equivalent load capacity.
Technical Specifications
Mechanical Properties
| Property | Test Method | Typical Value | Units |
|---|---|---|---|
| Tensile Strength | ASTM D638 | 30,000 | psi |
| Tensile Modulus | ASTM D638 | 2.5 × 10⁶ | psi |
| Flexural Strength | ASTM D790 | 30,000 | psi |
| Flexural Modulus | ASTM D790 | 1.2 × 10⁶ | psi |
| Compressive Strength | ASTM D695 | 40,000 | psi |
| Shear Strength | ASTM D2344 | 4,500 | psi |
| Bearing Strength | ASTM D953 | 40,000 | psi |
| Notched Izod Impact | ASTM D256 | 25 | ft-lb/in |
| Barcol Hardness | ASTM D2583 | 45-50 | – |
Physical Properties
| Property | Test Method | Value | Units |
|---|---|---|---|
| Specific Gravity | ASTM D792 | 1.80-1.95 | – |
| Water Absorption (24 hr) | ASTM D570 | <0.5 | % |
| Glass Content | ASTM D2584 | 33-35 | % by weight |
| Coefficient of Thermal Expansion | ASTM D696 | 1.0 × 10⁻⁵ | in/in/°F |
| Thermal Conductivity | ASTM C177 | 0.25 | BTU-in/hr-ft²-°F |
Electrical Properties
| Property | Test Method | Value | Units |
|---|---|---|---|
| Dielectric Strength | ASTM D149 | 500 | V/mil |
| Arc Resistance | ASTM D495 | 180 | seconds |
| Surface Resistivity | ASTM D257 | 10¹⁶ | ohms |
Load Capacity Data
2″ Deep Panel – Uniform Load Capacity (PSF)
| Span (inches) | L/150 Deflection | L/100 Deflection | L/75 Deflection |
|---|---|---|---|
| 12″ | 1,850 | 2,775 | 3,700 |
| 18″ | 820 | 1,230 | 1,640 |
| 24″ | 460 | 690 | 920 |
| 30″ | 295 | 440 | 590 |
| 36″ | 205 | 305 | 410 |
| 42″ | 150 | 225 | 300 |
| 48″ | 115 | 170 | 230 |
2″ Deep Panel – Concentrated Line Load (lb/ft width)
| Span (inches) | L/150 Deflection | L/100 Deflection | L/75 Deflection |
|---|---|---|---|
| 12″ | 2,400 | 3,600 | 4,800 |
| 18″ | 1,600 | 2,400 | 3,200 |
| 24″ | 1,200 | 1,800 | 2,400 |
| 30″ | 960 | 1,440 | 1,920 |
| 36″ | 800 | 1,200 | 1,600 |
1½” Deep Panel – Uniform Load Capacity (PSF)
| Span (inches) | L/150 Deflection | L/100 Deflection | L/75 Deflection |
|---|---|---|---|
| 12″ | 1,200 | 1,800 | 2,400 |
| 18″ | 530 | 800 | 1,065 |
| 24″ | 300 | 450 | 600 |
| 30″ | 190 | 285 | 380 |
| 36″ | 130 | 195 | 260 |
Safety Factor: 3:1 on ultimate strength. For impact loads, reduce values by 50%.
Product Dimensions
Standard Panel Sizes
| Panel Depth | Panel Size | Weight | Open Area | Bar Pattern |
|---|---|---|---|---|
| 1½” | 4′ × 6′ | 5.8 psf | 46% | 1½” × 1½” mesh |
| 1½” | 4′ × 8′ | 5.8 psf | 46% | 1½” × 1½” mesh |
| 2″ | 4′ × 6′ | 7.5 psf | 40% | 2″ × 2″ mesh |
| 2″ | 4′ × 8′ | 7.5 psf | 40% | 2″ × 2″ mesh |
Load Bar Configuration
- Top Bar Width: 0.25″ – 0.31″ (meniscus profile)
- Bottom Bar Width: 0.19″ – 0.25″
- Bearing Bar: Bi-directional square mesh pattern
- Standard Tolerance: ±5% on thickness, ±1/8″ on length/width
Resin Systems & Chemical Resistance
Available Resin Options
1. General Purpose Polyester (GPFR)
- Service Temperature: -20°F to 150°F continuous
- Chemical Resistance: Good for mild acids/alkalis
- Applications: General industrial, warehouses
- Cost: Most economical option
2. Isophthalic Polyester (IFR)
- Service Temperature: -20°F to 180°F continuous
- Chemical Resistance: Excellent for moderate concentrations
- Applications: Chemical processing, water treatment
- Fire Rating: Class 1 available (ASTM E84)
3. Vinyl Ester (VFR)
- Service Temperature: -20°F to 200°F continuous
- Chemical Resistance: High for aggressive chemicals
- Applications: Petrochemical, high corrosion environments
- Performance: Maximum chemical/temperature resistance
Chemical Resistance Chart (Vinyl Ester)
| Chemical | Concentration | Max Temperature | Rating |
|---|---|---|---|
| Sulfuric Acid | 10-50% | 180°F | Excellent |
| Hydrochloric Acid | 10-37% | 140°F | Excellent |
| Sodium Hydroxide | 10-50% | 180°F | Excellent |
| Chlorine (Wet) | Saturated | 140°F | Good |
| Salt Water | Saturated | 180°F | Excellent |
| Crude Oil | 100% | 200°F | Excellent |
| Gasoline | 100% | 100°F | Excellent |
Rating: Excellent (<5% property loss), Good (5-10% loss), Fair (10-25% loss)
Vehicle Load Specifications
Forklift Class Requirements
| Forklift Class | GVWR Range | Max Wheel Load | Min Panel Depth |
|---|---|---|---|
| Class I-II | 4,000-8,000 lbs | 3,200 lbs | 1½” |
| Class III | 10,000 lbs | 5,000 lbs | 1½” |
| Class IV-V | 12,000-20,000 lbs | 10,000 lbs | 2″ |
| Class VI-VII | 40,000+ lbs | 20,000 lbs | 2″ reinforced |
Wheel Load Distribution
- Contact Area: Actual wheel width + (2 × panel depth)
- Load Spread: 45° angle through panel thickness
- Dual Wheel Factor: 0.85 for paired wheels
- Dynamic Factor: 1.5 for moving loads, 2.0 for impact
Design Parameters
Deflection Criteria
| Application Type | Maximum Deflection | Typical Limit |
|---|---|---|
| Pedestrian Areas | L/200 | 0.125″ |
| Standard Industrial | L/150 | 0.25″ |
| Vehicular Traffic | L/100 | 0.375″ |
| Heavy Equipment | L/75 | 0.50″ |
Support Requirements
| Support Type | Min Bearing | Max Span | Max Overhang |
|---|---|---|---|
| Steel Beam | 1.0″ | Per load table | 6″ |
| Concrete | 2.0″ | Per load table | 4″ |
| FRP Angle | 1.5″ | Per load table | 6″ |
Safety Factors
- Standard Applications: 3:1 on ultimate strength
- Critical Applications: 5:1 on ultimate strength
- Impact Loading: Additional 2.0 factor
- Continuous Vibration: Additional 1.5 factor
Installation Requirements
Cutting Specifications
| Cut Type | Recommended Tool | Blade Type |
|---|---|---|
| Straight Cuts | Circular Saw | Carbide, 6-8 TPI |
| Curved Cuts | Jigsaw | Diamond grit |
| Holes <2″ | Hole Saw | Carbide tipped |
| Holes >2″ | Router | Carbide bit |
Fastening Systems
| Fastener Type | Application | Spacing | Load Capacity |
|---|---|---|---|
| M-Clips | Standard attachment | 12″ O.C. | 500 lbs/clip |
| G-Clips | Removable panels | 12″ O.C. | 400 lbs/clip |
| Hold-Down Clips | High vibration | 6″ O.C. | 250 lbs uplift |
Surface Options
Standard Surfaces
- Meniscus Top – Standard molded surface, good traction
- Grit Top – Applied aluminum oxide, maximum slip resistance
- Smooth/Covered – Sealed surface for cleanroom applications
Slip Resistance Values
| Surface Type | Dry COF | Wet COF | Test Method |
|---|---|---|---|
| Meniscus | 0.60 | 0.50 | ASTM F1679 |
| Grit Top | 0.90 | 0.80 | ASTM F1679 |
| Smooth | 0.40 | 0.30 | ASTM F1679 |
Fire Performance
Fire Ratings by Resin System
| Resin Type | Flame Spread | Smoke Index | Classification |
|---|---|---|---|
| GPFR Standard | 200-500 | 300-600 | Not rated |
| IFR Fire Retardant | ≤25 | ≤450 | Class 1 |
| VFR Fire Retardant | ≤25 | ≤450 | Class 1 |
Compliance Standards
- ASTM E84: Surface Burning Characteristics
- ASTM D635: Self-Extinguishing (<5 seconds)
- NFPA 130: Transit Vehicle Standards
- USCG 164.009: Marine Applications
Quality Standards
Manufacturing Compliance
- ANSI/ACMA FRP-01: Fiberglass Grating Standard
- ISO 9001:2015: Quality Management System
- AASHTO LRFD: Bridge Design Specifications
- ASCE Structural Plastics Design Manual
Testing Protocols
- Proof Load: 2.5× working load without failure
- Ultimate Load: 5× working load minimum
- Fatigue: 2 million cycles at working load
- Creep Resistance: <0.5″ after 1000 hours at 50% ultimate
Primary Applications
Industrial Facilities
- Heavy equipment platforms
- Forklift operating areas
- Chemical processing walkways
- Tank farm access platforms
- Mezzanine flooring
Infrastructure
- Wastewater treatment plants
- Electrical substations (non-conductive)
- Trench covers for utilities
- Bridge decking
- Marine terminals
Specialized Environments
- Corrosive chemical exposure areas
- High-temperature process areas
- Electrically sensitive zones
- Explosion-proof areas (with conductive option)
- Food processing facilities (with sealed surface)
Product Advantages
Performance Benefits
- 75% Weight Reduction vs. steel grating
- Corrosion Resistance – No rust or oxidation
- Non-Conductive – Electrical safety
- Low Thermal Conductivity – Personnel comfort
- Bi-directional Strength – Load distribution in both directions
Economic Benefits
- Long Service Life in appropriate applications
- Zero Painting/Coating maintenance required
- Reduced Installation Cost due to light weight
- No Replacement from corrosion damage
- Lower Structural Support requirements
FAQ
What load capacity does high load molded grating support?
High load capacity (HLC) molded grating supports H-20 loading (20,800 lbs concentrated, 32,000 lbs drive axle). Designed for forklift traffic up to 10,000 lbs with proper span design.
What panel sizes and depths are available?
Standard 6′ x 4′ panels in 1-1/2″ and 2″ depths. 48% open area with 1″ x 2″ bearing bars. Custom panel sizes and cutting available for specific project layouts.
What resin systems are offered?
Vi-Corr vinyl ester (excellent corrosion), Corvex corrosion resistant, FGI-AM fire retardant. All meet ASTM E84 Class 1 flame spread. Aluminum oxide grit top available for maximum slip resistance.
Can HLC grating support vehicular traffic?
Yes. Designed for forklift and light vehicular turning traffic. Supports 55% drive axle load (2,220 lbs) over 8″ + 4″ span, 85% over 11″ + 4″ span. Deflection limited to L/120.
What applications use high load molded grating?
Trench covers, ramps, storage/loading areas, assembly lines, machine platforms, and areas requiring forklift access in corrosive environments like chemical plants and wastewater treatment.
Is HLC grating lighter than steel grating?
Yes. about 60-75% lighter than carbon steel grating for equivalent loads. Reduces structural support requirements and installation costs significantly.
Does HLC grating meet fire standards?
Yes. ASTM E84 Class 1 flame spread rating (≤25). FGI-AM resin system provides fire retardancy for high-risk industrial applications.
How is HLC grating installed?
Standard M6-M10 stainless steel bolts or epoxy adhesive. 1/8″ expansion gap at joints. Compatible with FRP angles, channels, and support systems for corrosion-resistant platforms.
FAQ
What sizes are available for pultruded FRP angles?
Standard sizes from 1-1/4″ x 1-1/4″ x 1/4″ (0.438 lb/ft) to 6″ x 6″ x 1/2″. Equal and unequal leg configurations available. Custom sizes and tolerances upon request.
What is the weight advantage vs steel angles?
Pultruded FRP angles are approximately 75% lighter than steel by weight and 30% lighter than aluminum while maintaining comparable tensile strength. Example: 3″ angle = 1.2 lb/ft vs 4.1 lb/ft steel.
Is pultruded angle corrosion resistant?
Yes. 100% resistant to chemicals, moisture, saltwater, and industrial atmospheres. No painting, galvanizing, or maintenance required. 25+ year service life guaranteed.
What is the tensile strength?
Tensile strength 240-600 MPa (35-87 ksi) depending on glass content and resin. Exceeds typical steel yield strength while providing fatigue resistance and impact toughness.
What applications use pultruded FRP angles?
Industrial platforms, handrail supports, structural framing, equipment mounting, cooling tower frameworks, cable tray supports, and architectural features in corrosive environments.
Does pultruded angle conduct electricity?
No. Completely non-conductive with high dielectric strength. Safe for electrical substations, power plants, and applications requiring EMI shielding or worker safety.
Are pultruded angles dimensionally stable?
Yes. Low thermal expansion coefficient (10-15 × 10⁻⁶/°C vs steel’s 12 × 10⁻⁶). Maintains tight tolerances and straightness over wide temperature range (-50°C to +120°C).
Can pultruded angles be customized?
Yes. Custom colors (RAL system), fire-retardant UL94 V0, UV stabilized, high-temperature resins, and CNC fabrication for brackets/fittings. Minimum order quantities apply.
Ordering Information
Required Specifications
- Panel depth (1½” or 2″)
- Panel size (4’×6′ or 4’×8′)
- Resin system (GPFR, IFR, or VFR)
- Surface type (meniscus, grit, or smooth)
- Color (standard: gray, yellow, green, or custom)
- Load requirements (uniform and concentrated)
- Chemical exposure details
- Operating temperature range
Available Options
- Custom cut-outs for pipes/equipment
- Beveled edges for transitions
- Conductive surface for static control
- FDA-compliant resin systems
- Custom colors for safety coding
Request a Quote for High Load Molded Grating
Need high load molded grating for your project? Contact us for a quote and we will confirm specifications, lead time, and pricing.
All specifications are typical values. Actual performance depends on specific resin system, manufacturing process, and application conditions. Load ratings include appropriate safety factors per ANSI/FGMC standards.
