PV Fastener SUS304 VS SUS316 Selection Standard, Anti-corrosion Grade Comparison Guide For Outdoor PV Power Stations

PV Fastener SUS304 VS SUS316 Selection Standard, Anti-corrosion Grade Comparison Guide For Outdoor PV Power Stations

p>PV bracket fasteners require a 25+ year service life. Inland, coastal and industrial environments have completely different anti-corrosion requirements. Improper material selection causes rust spots, thread seizure and bracket loosening, leading to high maintenance costs.

1. Anti-corrosion Performance: SUS304 VS SUS316

Performance	SUS304 PV Fastener	SUS316 PV Fastener
Core Corrosion Resistance	General rainwater corrosion resistance	Superior chloride & salt spray resistance
Salt Spray Test	500~800h rust-free	1200h+ high-grade resistance
UV Aging Resistance	Good slight color change	Excellent anti-aging performance
Stress Corrosion Resistance	Average, prone to pitting in salt environment	Excellent anti-stress-cracking performance
Service Life	20+ years inland	25+ years coastal severe environment

2. Scene-based Material Selection Rules

1. Inland mountain & factory PV projects: SUS304 for cost-effective long-term anti-rust performance; 2. Riverside & lake area distributed PV: SUS316 for high humidity corrosion resistance; 3. Coastal & island PV power stations: Mandatory SUS316 to resist sea wind chloride corrosion; 4. Industrial acid-base area PV: Enhanced passivation SUS316 for chemical corrosion resistance.

3. PV Fastener Selection Avoidance Tips

1. Ban SUS201 for coastal projects: Easy mass rust and fracture; 2. SUS304 not suitable for high salt spray environment: Easy pitting rust and seizure; 3. Unified material for the same bracket system to avoid galvanic corrosion; 4. Mandatory stainless steel passivation to remove processing iron ions and prevent flash rust.