Drilling Method for Fixing Cable Trays

Cable trays are fixed by drilling pre-marked holes in the support structure and securing trays with clamps, bolts, and fasteners according to tray type and load requirements.

Preparation and Marking

Before drilling, mark the locations where the cable tray supports or clamps will be installed, ensuring proper alignment and spacing. Supports are typically spaced 1. 5 to 3 meters apart, depending on the tray type and load capacity.

Ensure the route is clear and level, and check for any obstructions or structural limitations.

Drilling Procedure

Select the appropriate drill bit for the support material (concrete, steel, or wood). For metal supports, use high-speed steel or cobalt bits; for concrete, use masonry bits. Drill holes at the marked positions on the support structure.

Ensure holes are straight and of the correct diameter to match the bolts or anchors being used.

For FRP or GR

P trays, pre-drilled holes in the tray covers or clamps are aligned with the support holes. Use pop rivets or bolts to secure the tray cover and clamps.

Fixing the Cable Tray

Place the cable tray or ladder on the supports.

Install H

D cover clamps or fixing clamps over the tray edges and align with drilled holes. Insert bolts and nuts (e.g., M10 flange nuts for metal trays) and tighten to the recommended torque, typically 6 Nm for cover clamps. For wider trays (600 mm and above), add additional bolts at the center and use anti-sag clamps to prevent deflection.

Ensure all joints, couplers, and fittings are securely bolted and aligned to maintain structural integrity.

Final Checks

Verify that the tray is level, aligned, and rigid. Ensure sufficient clearance for cable installation and maintenance. Confirm that all fasteners are tightened to the recommended torque and that expansion joints or connectors are properly installed.

By following these steps, cable trays are securely fixed, minimizing sagging and ensuring safe, long-term support for electrical and instrumentation cables. Proper drilling and fastening are critical for compliance with standards such as IEC 61537 and NEMA VE-1.