Guide for the selection and use of pallet cable tray

Cable tray (cable bracket) is the full name of a rigid structural system with closely supported cables, which is composed of straight segments, bends, components, arms (arm brackets) and hangers of trays or ladders. 
1) when cable trays, slots and their supports and hangers are used in corrosive environment, they should be made of corrosion-resistant rigid materials, or anti-corrosion treatment should be adopted, and the anti-corrosion treatment should meet the requirements of engineering environment and durability. 
2) in the section with fire prevention requirements, the cable bridge can add fire-resistant or non-flammable plates, nets and other materials to the cable ladder and tray to form a closed or semi-closed structure, and take measures such as painting fireproof coating on the surface of the bridge and its supports and hangers, its overall fire resistance should meet the requirements of the relevant national codes or standards. 
3) the aluminum alloy cable bridge should not be used in the places with high fire protection requirements. 
4) the selection of cable ladder, pallet width and height should meet the requirements of filling rate. Under normal circumstances, the filling rate in cable ladder and pallet should be 40% 50% and 50% 70% respectively, and the engineering development margin of 10% should be reserved. 
5) when selecting the load grade of the cable tray, the working uniformly distributed load of the cable tray should not be greater than the rated uniformly distributed load of the selected cable tray. If the actual span of the support and hanger of the cable tray is not equal to 2m, then the working uniformly distributed load should meet the requirements. 
6) under the condition of meeting the corresponding load, the specifications and dimensions of various components and hangers should match the straight line segment and bend series of pallet and ladder frame. 
7) when selecting the bending, up and down devices of the cable tray, it should not be less than the minimum allowable bending radius of the cable in the cable tray. 
8) for steel cable trays with a span greater than 6m and aluminum alloy cable trays with a span greater than 2m or bearing requirements greater than load grade D, the strength, stiffness and stability should be calculated or tested according to engineering conditions. 
9) when several groups of cable bridges are laid in parallel at the same height, the maintenance and overhaul distance between the adjacent cable bridges should be considered.