The cross arm system requires two suspension rods and two sets of five-piece kits for each arm. The recommended installation ratio is one cross arm for every 1. 5 to 2 meters of cable tray, ensuring sufficient structural integrity for larger and heavier installations. Galvanized crossarms for cable trays are typically made of Q235 low-carbon steel via rolling. more See our. Cable tray making machines are used to manufacture cable trays – an important component in electrical installations and industrial buildings for routing cables and wires safely. This comprehensive guide provides a detailed overview of cable tray making machine technology, working principles, types. This method primarily relies on two key accessories: hoisting frames and cross arms, each suited for different specifications of cable trays.