ASTM A755 Standard: The Premium Grade for Exterior Roofing & Siding
Our ASTM A755 Prepainted Galvanized Steel Coils are engineered specifically for high-end architectural exterior applications. This standard governs the application of organic coatings to metallic-coated steel sheets, ensuring that every coil delivered meets the rigid durability requirements for residential, commercial, and industrial roofing and siding.
Superior Coating Architecture for Extreme Weather
Under the ASTM A755/A755M specification, our PPGI coils feature a sophisticated multi-layer protection system designed to combat UV degradation and moisture infiltration:
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Substrate Quality: We utilize hot-dip galvanized (ASTM A653) or galvalume (ASTM A792) bases, providing the essential sacrificial protection needed for exterior longevity.
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Organic Coating Systems: Depending on your project’s environment, we offer high-performance finishes including Polyvinylidene Fluoride (PVDF) for maximum UV resistance, Silicone Modified Polyester (SMP) for enhanced chalk resistance, and High-Durability Polyester (HDP).
Rigorous Performance Testing & Compliance
To guarantee performance as an “Exterior Grade” material, our ASTM A755 coils undergo comprehensive testing:
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Color Retention & Gloss Uniformity: Our coatings are calibrated to maintain color integrity even under prolonged exposure to harsh sunlight (low $\Delta E$ values).
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Flexibility & Adhesion: Designed for precision roll-forming, our steel sustains 0T-2T bends without micro-cracking, ensuring the protective barrier remains intact at the ribs and valleys of roofing profiles.
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Corrosion Resistance: Tested via Salt Spray and Humidity cabinets to simulate decades of outdoor exposure.
Technical Specifications Table
| Parameter | ASTM A755 Requirement | Bomis Steel Capability |
| Substrate Standards | ASTM A653, A792, A875 | Fully Compliant |
| Top Coat Options | PVDF, SMP, HDP, PE | Customized per environment |
| Pencil Hardness | $\geq$ F – 2H | Optimized for scratch resistance |
| Salt Spray Resistance | Per standard hours | Exceeds 1000+ hours (PVDF) |
| T-Bend Test | No cracking or peeling | 0T to 2T |
Detailed Images （We support custom pattern design.）
Certification
ASTM A755 PPGI Steel Coil Application Scenarios
Usage Scenarios | Specific use | Reason for adaptation |
Roofing system | Roof panels / corrugated steel sheets for industrial plants, warehouses, commercial buildings, and prefabricated buildings. | Resistant to UV rays and temperature fluctuations, withstands wind loads and rain erosion, and has stable color. |
Wall enclosure | Exterior wall cladding, sandwich panel facings, interior partition walls, balcony panels | Highly decorative, can be processed directly, suitable for PU adhesive bonding, and compatible with modular construction |
Supporting components | Roller shutters, door and window frames, awnings, ventilation ducts | The coating has strong adhesion, is resistant to cracking and peeling during processing, and provides both protection and aesthetic appeal. |
Special buildings | Cold storage facilities, cleanrooms, agricultural greenhouses, prefabricated and modular buildings | Resistant to humidity and heat, resistant to salt spray, easy to clean, and meets the requirements for special environments such as food processing and medical facilities. |
Logistics equipment | Container side panels / roof panels, box truck body panels | Resistant to seawater and salt spray corrosion, not easily deformed during long-distance transportation, and requires low maintenance. |
Vehicle parts | Bus interior panels, car luggage racks, ship deck decorative panels | Lightweight, vibration-resistant, and with an anti-aging coating. |
FAQ about PPGI
1.what is ASTM A755 Galvanized Coil
ASTM A755/A755M is a standard published by the American Society for Testing and Materials (ASTM) for hot-dip coated and coil-coated pre-painted steel sheets/coils for outdoor construction. Its core principle is a hot-dip metallic substrate (galvanized/aluminum-zinc/pure aluminum) with an organic coating, specifically designed for outdoor exposed building components. It emphasizes weather resistance, formability, and coating adhesion, and specifies pre-painted steel sheets/coils with a hot-dip metallic substrate and a continuously coil-coated organic film. It is applicable to coils, cut-to-length sheets, and formed parts, covering corrugated sheets, profiled sheets, bent components, and other outdoor building products.
2.Are you a manufacturer or a trading company?
We are a factory with over 10 years of sales experience
3.How do you guarantee the quality?
1) Sourcing only from top-tier, certified mills.
2) Conducting our own rigorous in-house QC checks.
3) Providing a formal Mill Test Certificate and our quality warranty for every shipment.
