Municipal Water Treatment Plant — Cable Tray & Handrail System

The Challenge

A 120,000 m³/day municipal water treatment facility in Thailand required full replacement of its cable management and safety handrail systems. The existing galvanized steel cable trays and handrails had suffered severe corrosion after only 8 years of service due to constant exposure to chlorinated water vapor, high humidity (85–95% RH year-round), and tropical UV radiation. Annual maintenance costs had escalated to over USD 45,000, and several sections posed safety risks due to structural section loss exceeding 30%. The facility operator required a zero-maintenance solution with a minimum 25-year design life that could be installed during normal plant operation without process shutdowns.

Our Solution

F1 Composite supplied a complete FRP cable tray and handrail system comprising pultruded FRP cable ladder trays (600mm and 450mm widths, NEMA VE 1 compliant), FRP channel and angle sections for tray supports, pultruded round tube and square tube handrail assemblies with UV-stabilized polyester resin, and molded FRP grating stair treads with anti-slip surfaces rated to AS 4586 R11. The isophthalic polyester resin system was selected for its proven resistance to chlorinated water environments and tropical UV exposure. All profiles were factory-cut and pre-drilled to site dimensions, with stainless steel 316L fasteners for connections. The modular design allowed installation by a 4-person crew using hand tools only — no welding, no hot work permits, no crane required. Each cable tray section weighed approximately 75% less than the galvanized steel equivalent, enabling manual handling throughout the plant.

Results

The complete system — covering 2.8 km of cable tray runs and 1.2 km of handrail — was installed over 6 weeks with zero process interruption. The FRP system weighs 78% less than the replaced steel, eliminating all crane operations during installation. Post-installation load testing confirmed compliance with IEC 61537 cable tray load requirements and EN ISO 14122-3 handrail loading standards. The facility operator projects zero structural maintenance over the 30-year design life, representing estimated lifecycle savings of USD 850,000 compared to repeated galvanized steel replacement cycles. After 6 months of service, inspection confirmed no visible degradation, discoloration, or structural change in any FRP component.