Cable tray support bolt fixing

Cable trays are typically connected and secured using truss-head bolts, combination nuts, and joint plates to ensure stability and protect cables.

Types of Bolts and Nuts

Cable tray connections commonly use FRS M6 truss-head bolts paired with combination nuts for fastening straight or angled connectors. Other options include roofing bolts with nuts and flange nuts with fixed washers, which prevent the nut from falling during installation. The choice of bolt depends on the tray type, width, and load requirements.

Installation Procedure

Positioning the Connector: Insert the straight or angled connector into the inside of the tray rail. For trays 400 mm or wider, a joint plate is recommended to prevent transverse bending; for trays up to 300 mm, it is optional. Securing the Bolts: Pass the fastening screws from the inner side of the tray to avoid damaging cables, and secure them with combination nuts on the outer side.

Clamp or Joint Plate: For straight connectors, clamp the joint plate between the connectors before tightening the bolts. This ensures a stable and aligned connection. Additional Supports: Use mounting clamps, tray hangers, or suspension rods as needed to support heavy loads or maintain proper alignment.

Precautions

Always avoid direct contact of screws with cables to prevent damage. Ensure bolts are tightened securely but not over-torqued, which could deform the tray or fittings. Use pre-mounted turn buckles or covers where applicable to protect cables at bends, tees, or crossovers.

Materials and Compatibility

Cable tray bolts and fittings are typically made from galvanized steel, stainless steel, aluminum alloy, or FRP, depending on environmental conditions and load requirements. Ensure compatibility between the bolt type and tray material to prevent corrosion or mechanical failure.

Summary

For effective cable tray connection bolt fixing: use FRS truss-head bolts with combination nuts, insert connectors from the inner side, secure joint plates for wider trays, and employ additional supports as needed. Always follow manufacturer guidelines to protect cables and maintain structural integrity.