Basic Materials & Anti-Corrosion of Cable Trays

The basic construction material of cable trays is metal. However, when directly exposed to the natural environment without any protective layer, the metal is prone to reacting with water and air in nature, leading to corrosion that impairs the overall structural integrity of the tray. There are two common types of cable trays with protective layers: hot-dip Galvanized cable trays and electro-galvanized cable trays.

Differences in Production Processes:

Hot-Dip Galvanizing (HDG): Steel parts or castings are immersed in molten zinc, forming a protective coating on the surface consisting of zinc-iron alloy, pure zinc, or a combination of both.

Electro-Galvanizing: After chemical cleaning, the steel surface is immersed in an electroplating bath. Direct current is applied to the steel workpiece and zinc plates in the bath, depositing a zinc layer through electrochemical reactions.

Hot-Dip Galvanized Channel Cable Trays

Differences in Anti-Corrosion Performance:

Electro-galvanizing offers poor rust resistance due to uneven zinc deposition and insufficient zinc coating thickness during the electrolytic process, typically resulting in rust formation within 2-3 years. In contrast, hot-dip galvanizing provides a thicker coating with superior corrosion resistance.

During the initial installation phase, the zinc layer remains intact. However, over time and due to changes in the external environment, the integrity and quality of the coating may deteriorate. Therefore, regular inspection and maintenance of the cable tray surface are required after project completion. Any rust spots must be addressed promptly; otherwise, the rust will spread, compromising the overall project quality. The following construction requirements shall be followed during rust removal and maintenance:① Ambient temperature should be 13℃-30℃, but not lower than 5℃;② Relative humidity should not exceed 80%;③ Outdoor construction is prohibited during rain, fog, or strong winds;④ Construction should not be performed under intense direct sunlight.