Installation of Lightning Protection Devices for Container Houses

The installation of lightning protection devices for container houses should follow the principle of coordinated operation among the air-termination system, down conductors, and grounding devices. The construction sequence is from bottom to top, installing the grounding device, down conductors, and air-termination system in order, and ensuring that the material quality, welding process, and equipotential bonding meet the specification requirements.

I. Key Points for Grounding Device Construction

The grounding device is the core of the lightning protection system and needs to be realized using the foundation reinforcement of the building or independent grounding electrodes. If raft foundation reinforcement is used, more than two main reinforcements with a diameter of ≥Φ16 should be welded through and reliably connected to the main reinforcements in the concrete piles. A bow-shaped connection should be made at the deformation joints. If an independent foundation is used, the up-lead should be welded into a loop with the two reinforcements on the inner and outer perimeters of the base plate. All welding points should have the flux removed and be treated with anti-corrosion measures. The test points should be set at the designed positions above the ground for easy subsequent measurement of the grounding resistance.

II. Down Conductor Installation Specifications

Down conductors should use column main reinforcements (two main reinforcements with a diameter of ≥Φ16 or four diagonal main reinforcements with a diameter of ≥Φ10) as conductors, and form a path through cross-welding with Φ12 round steel. Key requirements include:

1. After welding, the flux should be removed and marked to ensure electrical continuity.
2. The roof should be divided into grids (≤20m×20m or 24m×16m) using Φ12 galvanized round steel, and the grids should be reliably connected to the down conductors.
3. The connection points between the down conductors and the lightning strip should be welded in series layer by layer to the top parapet to avoid breakpoints.

III. Air-Termination System Installation Details

The air-termination system includes lightning rods, lightning strips, etc., and should use hot-dip galvanized materials. The installation key points are as follows:

1. The support spacing should be 0.5 - 1m, with a height of 150mm. Smooth transitions and compensation settings should be made at the bends.
2. The joints of the lightning strip should be double-welded (with an overlap length of ≥6D), with full and leak-free welds. After welding, anti-rust treatment and silver paint application should be carried out.
3. Metal protrusions (such as vent caps and fan bases) should be welded to the lightning strip to form equipotential bonding.

IV. Handling of Special Scenarios

1. Settlement/Expansion Joint Handling: The lightning strip should have a margin reserved and be bent into a semi-circle to pass through the joints, preventing breakage due to structural deformation.
2. Metal Door and Window Grounding: Connect to the grounding body using a yellow-green copper core wire with a cross-sectional area of ≥4mm² to ensure a smooth path for lightning current discharge.
3. Power Distribution System Protection: The metal frame of the power distribution box should be reliably connected to the protective conductor, and the openable doors equipped with electrical appliances should be cross-connected with yellow-green wires.