Cable tray installation and fixing in vertical shafts

Secure cable trays in vertical shafts using properly positioned hangers, clamps, and threaded rods to maintain alignment, prevent slippage, and accommodate cable expansion.Preparation and PlanningBefore installation, plan the tray layout carefully, considering the shaft height, cable weight, and load distribution. Ensure that all tray sections, fittings, and supports are compatible and manufactured according to standards such as BS EN 61537 for cable trays and BS 6946 for channel supports . Avoid using the tray as a support for personnel or heavy equipment to prevent damage and ensure safety .Mounting Hangers and SupportsUse vertical threaded rods as hangers, positioning them at intervals that comply with the tray manufacturer's load specifications, typically supporting up to 318–340 kg per hanger with a maximum spacing of 3.6 m .Thread an upper hex nut onto the rod approximately 203 mm (8") above the tray bottom for initial positioning.Place round washers and clamps (single or double ladder clamps) around the tray siderails. Ensure the washer is between the hex nut and the clamp to distribute load evenly .Adjust the tray height by threading the lower hex nut until the tray reaches the desired vertical alignment.Securing the Cable TrayEnsure constant lateral clamping force using clamps with springs or adjustable tension to accommodate thermal expansion and contraction of cables .Avoid closed loops of ferromagnetic steel in the shaft to prevent magnetic interference and maintain high tensile strength .Maintain proper bend radius for cables exiting the tray to prevent conductor stress and insulation damage .For multiple adjacent trays, use double clamps to support them together, ensuring stability and alignment .Additional ConsiderationsPlan for cable expansion and contraction to prevent slippage or mechanical deformation during load cycling .Use high-tensile or armored cables where necessary to withstand vertical pulling forces .Ensure all tray sections are level and aligned before final tightening of nuts and clamps to prevent misalignment along the shaft .For complex vertical connections, elbows or bends may be used to transition between vertical and horizontal runs, ensuring smooth cable routing . By following these steps, cable trays can be safely and securely installed in vertical shafts, maintaining cable integrity and compliance with industry standards.