Non-galvanized cable tray connection between plates

Non-galvanized cable trays can be securely joined using splice plates and bolts, with careful attention to mechanical strength, corrosion protection, and grounding.

Connection Method

For non-galvanized cable trays, the most common and reliable method is using splice plates. These are flat metal plates with pre-drilled holes that align with the ends of two tray sections. The splice plate is positioned across the joint and secured with nuts and bolts, typically with lock nuts or spring washers to prevent loosening due to vibration or load stress . Each connection should have at least two bolts per side to ensure stability .

Steps for Installation

1. Align the tray sections so that the ends are flush and level.
2. Place the splice plate across the joint, ensuring all holes line up.
3. Insert bolts through the holes and secure with nuts and washers. Use a torque wrench to apply proper torque, ensuring a tight, vibration-resistant connection .
4. Check for gaps and adjust as necessary to maintain a straight run and proper load distribution.

Corrosion Considerations

Non-galvanized steel is prone to rust and corrosion, especially in humid or industrial environments. To mitigate this:

• Apply a protective coating such as zinc-rich paint or epoxy on the splice plate and exposed tray edges.
• Consider using stainless steel bolts and washers to reduce galvanic corrosion between fasteners and tray material .
• Regularly inspect joints for signs of corrosion and reapply protective coatings as needed.

Grounding and Bonding

Even if the cable tray is non-galvanized, it may still serve as an Equipment Grounding Conductor (EGC) if installed according to electrical codes. To ensure proper grounding:

• Use grounding clamps to bond each tray section to the EGC, especially at splice plate connections .
• Avoid bare copper conductors in aluminum trays to prevent electrolytic corrosion; use insulated conductors with tin or zinc-plated connectors where bonding is required .
• Ensure continuity across all tray sections to maintain a reliable grounding path.

Maintenance and Safety

• Tighten bolts periodically to prevent loosening from vibration or thermal expansion.
• Inspect protective coatings and reapply as necessary to maintain corrosion resistance.
• Ensure that the tray remains level and supports the intended cable load without sagging. By following these practices, non-galvanized cable tray connections using splice plates can achieve long-term mechanical stability, electrical safety, and ease of maintenance .