The standard galvanizing thickness for cable trays typically ranges from 45µm for thinner components to 65µm or more for heavy-duty or outdoor applications.

Electro-Galvanized Cable Trays

For electro-galvanized trays, the minimum local zinc thickness is generally 45µm, corresponding to a coating mass of at least 325 g/m² for tray sheets with thicknesses between 1.5mm and 3mm. Heavier components, such as brackets or supports thicker than 3mm, require a minimum thickness of 55µm. The coating must be continuous, uniform, and free of defects like bare spots or blisters, while minor surface marks are acceptable .

Hot-Dip Galvanized Cable Trays

For hot-dip galvanized trays, which are preferred for outdoor or highly corrosive environments, the zinc coating thickness is typically ≥65µm. This ensures long-term corrosion resistance and durability, as hot-dip galvanizing provides strong bonding between the zinc layer and the steel substrate . The thickness may be adjusted depending on environmental exposure, with more aggressive conditions requiring thicker coatings.

Factors Affecting Galvanizing Thickness

• Tray component thickness: Thicker side plates or rungs may require higher zinc thickness.
• Environmental conditions: Indoor general corrosion environments may allow thinner coatings (≥12µm for electroplated zinc), while outdoor or industrial environments require thicker coatings (≥65µm for hot-dip zinc).
• Standards compliance: IEC 61537 and national standards like GB/T 26941.1-2011 or T/CECS 31-2017 define minimum coating requirements and testing methods .

Summary

• Electro-galvanized trays: 45–55µm depending on component thickness.
• Hot-dip galvanized trays: ≥65µm for outdoor or high-corrosion environments.
• Coating must be uniform, defect-free, and meet local and mean thickness requirements. Selecting the appropriate galvanizing thickness ensures long-term corrosion protection, structural integrity, and compliance with international and national standards.