Cable tray elbow splicing

Cable tray elbow splicing is achieved using specialized splice plates that securely join horizontal or vertical elbow sections, ensuring structural continuity and proper cable support.

Overview of Elbow Splicing

Cable tray systems often require elbows to navigate changes in direction, either horizontally or vertically. To maintain mechanical strength and electrical continuity, splice plates are used to connect these elbow sections to straight tray runs or other elbows. Splice plates are designed to fit specific tray types and elbow configurations, including fixed angle, adjustable, horizontal, and vertical applications .

Types of Splice Plates

1. Straight Splice Plates – Used to join straight sections or extend elbows in a linear alignment.
2. Fixed Angle Horizontal/Vertical Plates – Designed for elbows with a predetermined angle, typically 90°, to maintain precise directional changes.
3. Adjustable Horizontal/Vertical Plates – Allow minor angle adjustments to accommodate site-specific installation requirements.
4. Expansion Straight Plates – Used where thermal expansion or contraction may occur, providing flexibility without compromising structural integrity .

Installation Guidelines

• Alignment: Ensure the elbow sections are properly aligned with the adjoining tray sections before attaching splice plates.
• Fastening: Use the recommended bolts or push pins as specified by the manufacturer. For example, some systems require M6x16 bolts or patented push pins for secure attachment .
• Support Spacing: Maintain proper distance from supports, typically L/5 from the support, to prevent sagging or misalignment .
• Hole Considerations: Pre-punched holes in trays and elbows simplify installation, but ensure that splice plates are centered and all fasteners are tightened evenly to avoid gaps or misalignment .
• Material Compatibility: Use splice plates made from the same material as the tray (e.g., fiberglass, aluminum, or steel) to prevent galvanic corrosion and maintain mechanical strength .

Best Practices

• Verify that the splice plates are compatible with the specific elbow radius (short or long radius) and tray type.
• For vertical elbows, ensure that the splice plates are designed to handle the weight of the cables and maintain proper grounding if required.
• Always follow manufacturer guidelines for torque specifications and installation sequence to ensure safety and compliance with UL or NEMA standards . By following these guidelines, cable tray elbow splicing can be performed efficiently, maintaining both structural integrity and cable protection throughout the system.