Cable tray reverse right-angle bend

A reverse right angle bend in a cable tray is a 90° bend that redirects the tray in the opposite direction, typically fabricated using pre-made fittings or on-site bending techniques.Understanding Reverse Right Angle BendsA reverse right angle bend allows a cable tray to change direction sharply, often to navigate around obstacles such as structural columns, pipes, or HVAC ducts. These bends are commonly used in both horizontal and vertical planes, depending on the routing requirements .Fabrication MethodsPre-fabricated 90° fittings: Many manufacturers provide ready-made 90° bends for steel or wire mesh cable trays, which can be installed directly onto the tray system . These fittings ensure consistent angles and maintain proper cable bending radii.On-site bending: If pre-fabricated fittings are unavailable, a reverse right angle bend can be made using a cable tray bending machine, crimping tools, or even a metal bar for smaller trays . The process involves marking the bend points, lifting the tray sides, and carefully forming the 90° angle while maintaining the tray's structural integrity.Wire mesh trays: For wire mesh cable trays, bends can be created live on-site using a bolt cutter to cut and form the tray, with protective caps applied to cut ends to prevent cable damage .Installation ConsiderationsBending radius: Ensure the bend does not violate the minimum bending radius of the cables to prevent damage during installation .Support spacing: Secure the tray at least twice along the length of the bend and use appropriate brackets or riser links to maintain stability .Offset calculation: For complex routing, calculate the horizontal and vertical offsets to determine the required straight tray lengths between bends. Tools and multipliers can simplify this calculation .Smooth transitions: Avoid sharp transitions that could make cable pulling difficult, especially for thick or high-voltage cables. Angles of 30° or 45° may be used in combination to create a smoother path if space allows .Software AssistanceFor design and planning, tools like Revit with GreaterBIM Smart Bend add-in allow engineers to model reverse right angle bends accurately in 2D and 3D, ensuring proper alignment and reducing on-site adjustments .SummaryA reverse right angle bend is essential for navigating obstacles in cable tray systems. It can be achieved using pre-fabricated fittings, on-site bending, or wire mesh modifications, with careful attention to bending radius, support, and offset calculations to ensure safe and efficient cable installation .