What size are the bolts used in cable trays

Cable tray supports commonly use M6 bolts for light to medium loads and 10mm anchor bolts for heavier installations. Common Bolt SizesM6 Bolts: Frequently used for standard cable tray installations, especially for ladder-type or perforated trays. Typical lengths range from 12mm to 16mm, paired with serrated flange nuts to provide vibration-resistant fastening.

These bolts are suitable for electrical, mechanical, and construction applications where moderate load support is required. 10mm Anchor Bolts: For heavier cable trays or when supporting multiple large cables, 10mm anchor bolts are often recommended. Each bolt can have a basic tensile load capacity of around 5 kN, making them suitable for supporting cable trays with significant weight, such as 600mm ladder-type trays carrying armored cables.

Other Sizes: In some cases, 1/4" (≈6. 35mm) plastic bolts or 3/8" (≈9. 5mm) steel bolts are used for specific wall or stand-off supports, depending on the tray width and mounting configuration.

Considerations for Bolt Selection

Load Capacity: Ensure the bolt size matches the weight of the cable tray and the cables it carries. Heavier trays require larger diameter bolts or multiple fasteners per support point. Material and Finish: Steel bolts with zinc plating or black powder coating are common for corrosion resistance.

Stainless steel may be used in outdoor or high-humidity environments. Compatibility: Use bolts compatible with the tray type (ladder, perforated, or solid-bottom) and the support structure (wall, ceiling, or stand-off brackets). Installation: Serrated flange nuts or truss head bolts are preferred for vibration resistance and secure fastening.

By selecting the appropriate bolt size and type, you ensure safe, durable, and code-compliant cable tray installations.