Thickness of fireproof trapezoidal cable trays

Fireproof trapezoidal cable trays typically have a metal thickness ranging from 1.2 mm to 2.0 mm, depending on load requirements and fire-resistance specifications.Material and FireproofingFireproof trapezoidal cable trays are designed with metal structures coated with fire-resistant materials to prevent flame spread and protect cables during a fire event, often rated for 30 to 60 minutes of fire resistance . The fireproof coating is generally thin but highly adherent, ensuring both flame retardancy and mechanical durability . Common materials include galvanized steel, stainless steel, or aluminum alloys, selected based on environmental conditions and corrosion resistance .Thickness ConsiderationsThe tray thickness is determined by several factors:Mechanical load: Heavier cable bundles require thicker metal to prevent deformation or failure under full load .Fire-resistance rating: Higher fire-resistance durations may require slightly thicker trays or additional coating layers .Tray span and support spacing: Longer unsupported spans or wider trays may necessitate increased thickness for structural integrity . Typical thickness ranges for fireproof trapezoidal trays are:Light-duty trays: 1.2–1.5 mmMedium-duty trays: 1.5–1.8 mmHeavy-duty trays: 1.8–2.0 mm These values ensure sufficient mechanical strength and fire protection while maintaining manufacturability and cost efficiency .Installation and ComplianceWhen installing fireproof trays, it is important to follow technical standards for alignment, support, and load distribution. Horizontal deviation should be ≤2 mm per meter, and vertical deviation ≤3 mm per meter to maintain structural integrity . Compliance with UL, NEMA, or CE standards is recommended to ensure safety and regulatory adherence .SummarySelecting the correct thickness for fireproof trapezoidal cable trays depends on the weight of cables, span, and required fire-resistance rating. Standard practice ranges from 1.2 mm for light loads to 2.0 mm for heavy-duty applications, with fireproof coatings applied to enhance flame resistance and protect critical electrical systems .