How long should the fireproof sealing of the cable tray be

Fireproof sealing partitions should be installed every 80–100 meters for flame-retardant cables and every 60 meters for non-flame-retardant cables.

Recommended Intervals

According to technical guidelines, the spacing of fireproof sealing partitions depends on the type of cable: Flame-retardant cables: Install a fireproof partition every 80–100 meters along the cable tray. Non-flame-retardant cables: Install a fireproof partition every 60 meters. These partitions act as fire stops to prevent fire from spreading along the cable tray in case of ignition.

The partitions should be constructed using fireproof partition plates at least 10 mm thick, with the middle filled using inorganic putty, fireproof bags, or refractory bricks.

Sealing Materials and Construction

Wrap the cables with organic putty around the fireproof wall, ensuring a thickness of at least 20 mm and a width of no less than 30 mm. Compactly seal both sides of the fireproof wall with organic putty, maintaining a smooth and flat surface. Seal gaps at the bottom of the cable trench and around the fireproof wall using organic putty with a minimum thickness of 10 mm and width of 20 mm.

Additional Considerations

Ensure that all gaps inside and around metal trunking or cable trays are tightly sealed without visible cracks or voids. Use firestop packs, firestop mastic, or fire-resistant mineral wool in an orderly sequence to maintain fire integrity. For large openings, install a fire-resistant backing plate before sealing to enhance fire protection.

Periodically inspect fireproof trays and sealing materials to ensure long-term effectiveness and compliance with safety standards. By following these intervals and construction methods, cable trays can maintain fire safety and prevent the spread of fire through electrical installations.