Standard Thickness of Large-Span Galvanized Cable Trays

For large-span galvanized cable trays, the typical steel thickness ranges from 1. 5 mm to 3. 0 mm depending on span, load, and galvanization type.

Material Thickness and Galvanization

The thickness of galvanized cable trays is primarily determined by span length, load capacity, and environmental conditions. For large-span trays (spans exceeding 3 meters), manufacturers typically use steel thickness between 1. 5 mm and 3.

0 mm. Hot-dip galvanized trays generally require slightly thicker steel than electro-galvanized trays to achieve equivalent structural strength and corrosion resistance, as the zinc coating adds a protective layer but does not significantly increase mechanical strength ( ). Standards and ComplianceIEC 61537 specifies mechanical strength, corrosion resistance, and load testing for metallic cable trays, ensuring that trays can safely support cables over long spans ( ).

NEMA and AST

M standards provide guidance on galvanization thickness and coating quality. Hot-dip galvanization typically results in a zinc layer of 55–85 µm, while electro-galvanization produces thinner coatings around 10–25 µm, influencing the choice of base steel thickness ( ).

Design Considerations for Large Spans

Support spacing: Longer spans require closer support intervals or thicker tray material to prevent excessive deflection ( ). Load capacity: The tray thickness must accommodate the total weight of cables, including future expansion. For heavy-duty industrial applications, thicker steel (2.

0–3. 0 mm) is recommended. Environmental factors: In corrosive or outdoor environments, hot-dip galvanization with thicker steel is preferred for durability ( ).

Practical Recommendations

For spans up to 3 meters, 1. 5–2. 0 mm galvanized steel is generally sufficient.

For spans between 3–5 meters, 2. 0–2. 5 mm thickness is recommended.

For spans exceeding 5 meters or heavy cable loads, 2. 5–3. 0 mm steel ensures structural integrity and compliance with IEC 61537 ( ).

Selecting the correct thickness ensures mechanical stability, safety, and long-term corrosion resistance, which is critical for industrial and commercial electrical installations.