FRP cable trays support power and instrumentation cables across corrosive zones in chemical plants and offshore platforms. Available in flame-retardant resin formulations, they resist the acidic fumes and salt mist that eat through metal trays within a few seasons.
A fiberglass cable tray weighs roughly one‑third of an equivalent steel tray, yet the pultruded side rails and rungs carry the same NEMA load classes. The open‑ladder design allows cables to drop in from above without threading, and the smooth, rounded edges prevent insulation abrasion during pulls. For non‑metallic cable management in classified areas, the non‑sparking, non‑magnetic properties eliminate the risk of accidental arc ignition and stray current loops—details that electrical engineers in hydrogen‑sulphide‑rich processing units take seriously.
In offshore topside and coastal plants, an FRP ladder tray run stays visually and structurally intact without the coating touch‑ups that galvanised steel demands. Salt fog testing per ASTM B117 routinely exceeds 2,000 hours with no under‑film corrosion because there is no film to breach—the entire section is homogeneous resin reinforced with glass. Maintenance teams also note that the lighter weight allows a single electrician to carry a 3‑m tray section up a stair tower, which speeds up tray modifications during turnarounds.
Typical Dimensions & Load Classes
| Standard widths | 150, 300, 450, 600 mm (6, 12, 18, 24 in) — NEMA VE‑1 |
|---|---|
| Side rail height | 100 or 150 mm (4 or 6 in) |
| Rung spacing | 150 mm (6 in) standard; 300 mm (12 in) for heavy loads |
| Load class | NEMA Class A (light), B (medium), or C (heavy) depending on configuration |
| Resin system | Isophthalic polyester (standard); vinyl ester for high‑H₂S or chemical exposure; brominated resin for flame retardancy |
| Fire performance | Flame spread index ≤ 25 (ASTM E‑84); self‑extinguishing grades available |
| Length | 3 m or 6 m (10 or 20 ft); cut‑to‑length service available |
| Weight | Approx. 4–10 kg/m (2.7–6.7 lb/ft) depending on width and class |
Each tray section ships with 316 stainless steel splice plates and hardware. The splices act as expansion joints, absorbing thermal movement without stressing the tray. For projects that need a consistent non‑metallic specification, the same resin system can run through all the access components—ladders, handrails, and trays—eliminating galvanic corrosion at transition points. The trays also integrate with cable management systems that include bends, tees, and risers.
Proven in Field
“The metal cable trays in our sulphur recovery unit were perforated by acid condensation within three years. We replaced the entire run with FRP ladder trays of the same width—zero structural degradation after four years, and the electricians appreciate not having to repaint every outage.”
— Excerpt from Power Plant Cable Tray Retrofit