Steel cable trays are applied in industrial engineering
      Cable trays have been widely used in industrial and civil engineering. Their varieties include steel cable trays, aluminum alloy cable trays, and fiberglass reinforced plastic cable trays. The most commonly used in engineering are steel cable trays; however, in the current electrical and automation surface construction and inspection standards, as well as quality assessment specifications, there are few regulations for steel cable trays, and there are inconsistent and contradictory provisions presented.
Steel cable tray (hereinafter referred to as tray)
    A collective term for the rigid structural system composed of steel cable tray steel ladder or tray straight sections, bends, and variable-width straight sections, as well as supports and hangers, used to support cables with closely connected continuous structures (trays are divided into perforated, non-perforated, and assembled types. Small standard non-perforated trays are often called wireways, used for laying wires).
Fill ratio
    Also known as cross-sectional utilization rate; it is the percentage of the total cross-section of cables and wires, including their insulation, laid in the tray relative to the internal cross-section of the tray.
Steel cable tray supports and hangers
    A collective term for the supporting components that bear the tray, including columns, brackets, straight, L-shaped, and door-type supports;
Additional concentrated load
    Loads that can be added to the tray during installation and maintenance, aside from the self-weight of the tray and cables (wires).