Cable tray bend modification

Cable tray bends can be modified by adjusting the bend radius in design software or physically reshaping the tray using proper tools and techniques.

Adjusting Bend Radius in Design Software

In software like Autodesk Revit, you can modify a cable tray bend by selecting the bend, clicking the dimension for the radius, and entering a new value. The default bend radius is typically equal to the tray width measured between the inside edges, but you can specify a different multiplier in the Type Properties dialog to suit your design requirements. This ensures that the bend complies with cable bend-radius standards and avoids overcrowding.

Physical Bending Techniques

For on-site modifications, cable trays can be bent using specialized tools or improvised methods: Cable tray bender: A tool designed for precise bends in metal trays, suitable for various tray sizes and materials. Manual methods: For steel trays, a metal bar or crimping technique can create internal 90-degree bends without a bending machine, though care must be taken to avoid deforming the tray. Pre-manufactured bends: When possible, using factory-made bends ensures consistent radius and structural integrity.

Considerations for Bend Geometry

When modifying bends, it is important to account for: Bend radius and cable fill: Cables on the inside of a bend travel a shorter distance than those on the outside, which can lead to crowding. Calculating the fill capacity based on the inside radius helps prevent exceeding tray limits. Tray type: Ladder trays allow easier access and better fill management, ventilated troughs reduce usable space due to slats, and wire mesh baskets have lower fill capacity but are easier to install.

Safety and integrity: Inspect trays for dents or cracks before bending, and clean them to ensure accurate measurements and smooth bends. Steps for Modifying a Cable Tray BendInspect and clean the tray to remove debris and check for damage. Measure and mark the desired bend location and angle.

Choose the appropriate bending method or tool. Apply the bend gradually, ensuring the tray maintains structural integrity. Verify that the bend radius meets cable fill and installation requirements.

By following these guidelines, you can safely and effectively modify cable tray bends while maintaining compliance with electrical and mechanical standards.