Cable tray bridging bolts

Cable tray bridging bolts are used to securely connect, stabilize, and provide electrical continuity between cable tray sections, often with anti-loosening nuts or washers.

Purpose of Bridging Bolts

Bridging bolts are essential for: Mechanical stability: They secure cable tray sections to each other or to support brackets, preventing movement under load or vibration. Electrical continuity: In metal cable trays, bridging bolts help maintain a conductive path for grounding and bonding, especially in stainless steel or aluminum trays. Compliance with standards: Properly installed bolts ensure adherence to DIN EN 61537 and other industrial installation standards, supporting safe and reliable cable routing.

Installation Guidelines

Number of bolts: Typically, at least two bolts are used at each connection point to ensure stability and conductivity. Anti-loosening hardware: Use anti-loosening nuts or washers to prevent bolts from loosening due to vibration or thermal expansion. For galvanized trays, anti-loosening nuts are preferred over washers.

Grounding connections: Stainless steel and aluminum trays often have dedicated grounding bolt holes. Copper stranded wires with crimped copper connectors can be used to bridge trays electrically, with a minimum cross-sectional area of 4 mm². Direct crimping: For conductive connections, bolts can be used with crimped tinned copper connectors or insulated multi-strand copper wires to ensure proper grounding.

Material Considerations

Galvanized steel trays: Bridging can be achieved with anti-loosening nuts or washers; grounding of connecting plates is not always required. Stainless steel and aluminum trays: Use special grounding bolt holes and ensure conductive bridging with copper wires or welded bolts on supports.

Best Practices

Ensure all bolts are tightened to manufacturer-recommended torque values. Avoid using more than two crimped wires at a single crimping point to maintain reliable electrical connections. Verify that bridging bolts and grounding connections are compatible with the tray material to prevent corrosion or galvanic reactions.

Consider welding bolts on supports for long runs or high-vibration environments to enhance stability. Proper use of cable tray bridging bolts ensures structural integrity, electrical safety, and compliance with industrial standards, making them a critical component in cable management systems.