Key Construction Points and Installation Methods for Hot-Dip Galvanized Bridge Channels

Cable tray selection and design: High and low voltage lines should be laid in separate channels; high and low voltage should be separated in the junction box.(When boxes cross, metal separation plates must be used to isolate them; the conductors for strong and weak electricity should not come into direct contact within the cable trays. The various wiring in ground cable trays is only allowed to be connected at the outlet of the branching box. During construction and installation, all cable trays should be connected to form a reliable grounding whole.

1Measurement and Positioning:

Mark the installation location of the bridge with string lines, determine the fixed position of the brackets, and make clear markings. For the positioning of the bridge in the shaft, first use the suspended wire method to determine the installation baseline. If the reserved hole is not suitable, adjust it promptly and make necessary repairs.  

2Cable tray manufacturing and installation

We design the elevation and bridge specification, locate them, and then manufacture the brackets according to the measured dimensions, which are produced in a factory. Install brackets along the bottom of the beam or against the wall in areas without a suspended ceiling, or in the suspended ceiling or against the wall in areas with a suspended ceiling. In public areas without a suspended ceiling, combine structural components, consider architectural aesthetics, and ease of maintenance, and use brackets installed against the wall or column, or install under the truss stringers. Fixed brackets installed against the wall use expansion bolts, and the spacing between brackets should not exceed2At the connections of straight and non-straight segments, at the deformation joints of buildings, and in the middle of non-straight segments with a bend radius greater than 300mm, additional support and suspension brackets should be installed. The installation of the support and suspension brackets should ensure that the bridge rail is level or vertical as required.

3Cable tray

a.For special-shaped bridge supports, submit the measured dimensions to the material supplier, who will manufacture them based on these dimensions, reducing on-site processing. The bridge support material, model, thickness, and accessories meet the design requirements.

b.Prior to bridgeway installation, coordination with all relevant specialties is mandatory to avoid conflicts with large-diameter fire hoses, sprinkler pipes, hot and cold water pipes, drainage pipes, as well as air conditioning and exhaust equipment.

c.Lift the bridge to the designated position and secure it to the bracket with bolts. Be meticulous in checking dimensions at turns. The bridge should align with the slope of the building. For bridges on the walls of an arched building, the arc should match the building's shape. Connect bridges using junction plates, with half-round head bolts for the connections, placed on the inside of the bridge. The gaps between bridges must meet design specifications to ensure the bridges of a single system are integrated as one.

d.The bridge for crossing the expansion joints of buildings should be properly treated with expansion joints according to the company's standard "Installation Technology for Steel Cable Bridgeways." When the straight section of the steel bridgeway exceeds 30 meters, a thermal expansion and contraction compensation device should be installed.

e.Bridge supports are installed horizontally and vertically, neat and aesthetically pleasing, with consistent spacing, and securely connected. The level deviation within the same horizontal plane does not exceed 5mm/m, and the straightness deviation does not exceed 5mm/m.

4Grounding treatment

Grounding treatment for cable trays: The zinc-plated trays can utilize zinc-plated connecting plates as jumper wires to connect the trays into a single unit. Zinc-plated spring washers are applied to the two connecting bolts at both ends of the connecting plate, and the trays are connected using not less than4mm2Soft copper wire is used for cross-connection, and then the bridge is connected to the grounding wire to form an electrical path. The bridge should have at least two connections to the main grounding line.

5Multi-layer bridgeway installation; layered bridgeway installation

First install the upper layer, then the lower layer. Leave sufficient space between the upper and lower layers, which is conducive to later cable laying and maintenance. The clear distance between horizontally adjacent bridgeways should not be less than50mmThe spacing between levels should be no less than 150mm based on the bridge width, and at least 0.5m away from the low-voltage cable bridge.

Yunnan Ziyang Zongjiu Industry and Trade Co., Ltd. is a cable tray manufacturer in Yunnan, specializing in tray manufacturing for years. Our factory offers standard specifications and galvanized, fire-resistant, and easy-to-install槽trays. If you're in need of cable trays, feel free to call for detailed discussions!!