Installing vertical shaft cable trays

Vertical shaft cable trays must be installed with proper material selection, secure support, correct spacing, and strict adherence to safety standards to ensure reliable and safe cable management.

Material and Design Considerations

Vertical cable trays are typically made from cold-rolled steel, galvanized steel, or aluminum alloy, with surface treatments such as hot-dip galvanizing or electrostatic spraying to meet corrosion resistance standards (GB/T 13912) and fire resistance (GB 8624 Class B1) requirements . Each tray unit includes the tray, cover, and connectors, with a load-bearing capacity of at least 200 kg/m. The tray path should avoid interference with ventilation ducts, water pipes, and other services, maintaining a minimum clearance of 300 mm. When multiple trays are installed in layers, power and weak-current trays must be spaced at least 150 mm apart, with isolation plates at crossings .

Support and Fixation

The support system is critical for vertical cable trays. Supports must be installed according to design specifications, ensuring stability and load distribution. Firestop spaces must be reserved when passing through fire compartments, using GB 23864-certified firestop materials . Proper fixation of cables within the tray is essential, avoiding closed loops of ferromagnetic steel to prevent electromagnetic interference .

Cable Pulling in Vertical Shafts

Cable pulling in vertical shafts is high-risk due to gravitational forces. It is recommended to use professional installation teams with experience in vertical installations . Key precautions include:

• Considering the weight of the cable and the tensile strength to prevent rupture.
• Using fail-safe mechanisms such as secondary steel wires or synchronized cable pushers to prevent free fall.
• Ensuring proper snaking and fixation of cables once installed, avoiding sharp bends and maintaining minimum bend radius .

Installation Procedure

1. Review Approved Shop Drawings: Confirm tray layout, lengths, and locations.
2. Material Inspection: Verify all trays, ladders, and accessories for compliance and damage before installation .
3. Support Installation: Install brackets, struts, or hangers according to design, ensuring vertical alignment and load capacity.
4. Tray Assembly: Connect tray sections securely, maintaining proper spacing and alignment.
5. Cable Laying: Pull or push cables carefully, using protective grips and avoiding excessive tension.
6. Final Checks: Inspect for proper fixation, spacing, and compliance with fire and safety standards.

Safety and Compliance

• Only qualified personnel should perform installation, following local electrical codes and occupational safety regulations .
• Ladder trays are mechanical support systems, not walkways or lifting devices.
• Proper storage and handling of trays prevent damage and corrosion before installation. By following these guidelines, vertical shaft cable trays can be installed safely, ensuring structural integrity, fire safety, and reliable cable management in high-rise buildings, industrial plants, or other vertical shaft applications .