Cable tray installation inside vertical shaft

Vertical cable tray installation requires careful planning, secure support, and adherence to safety standards to manage cable weight and prevent mechanical failure.

Key Considerations

Safety and Planning: Installing cable trays in vertical shafts is inherently risky due to the gravitational forces acting on the cables. Only trained professionals should perform these installations, and a detailed plan must account for cable weight, pulling forces, and potential hazards . Support and Fixation: Vertical trays must be supported using vertical hangers, clamps, and brackets. Center-hung supports allow easier cable deposition from each side, while threaded rods with washers and hex nuts secure the tray sections in place . Maximum load per hanger typically ranges from 318 kg to 340 kg, with support spacing up to 3.6 m . Cable Handling: When pulling cables vertically, consider the tensile strength of the cable and use pulling grips or steel wire socks to prevent rupture. Fail-safe mechanisms, such as secondary steel wires or synchronized cable pushers, are recommended to prevent free fall in case of cable failure . Tray Material and Type: Cable trays can be made of steel, aluminum, or other corrosion-resistant materials, selected based on environmental conditions and mechanical requirements . Ladder-type trays are commonly used for vertical runs due to their strength and ease of cable placement . Installation Method:

1. Position vertical hangers at calculated intervals.
2. Thread upper hex nuts onto all-thread rods above the tray bottom.
3. Place clamps around tray siderails, add washers, and lift the tray section so the rod passes through the clamp.
4. Secure with a second washer and hex nut, adjusting to the desired vertical position .
5. Ensure proper snaking of cables to avoid sharp bends and maintain minimum bend radius. Mechanical and Thermal Considerations: Avoid closed loops of ferromagnetic steel to prevent electromagnetic interference. Ensure that cable expansion and contraction during load cycling do not cause slippage or insulation damage . Standards Compliance: Installations should comply with BS EN 61537 for cable trays and BS 6946 for channel support systems, ensuring mechanical integrity and safety .

Summary

Vertical cable tray installation demands secure mechanical support, careful cable handling, and adherence to standards. Proper planning, use of high-strength materials, and fail-safe mechanisms are essential to prevent accidents and ensure long-term reliability of the cable system .