I. Pre-Installation Preparation​

1. On-Site and Product Inspection: Confirm that the installation location complies with the design drawings, and measure the geological conditions of the excavation area; check that the ductile iron surface box has no cracks or deformation on its appearance, its dimensions match the design, and all accessories are complete and undamaged.​​

2. Tool and Material Preparation: Prepare excavation tools, compaction equipment, measuring tools, fixing materials, and protective gear; precast C25 concrete pedestals in advance.​

3. Foundation Pre-Treatment: Excavate the foundation pit according to the design elevation, with a depth that ensures the top of the surface box is flush with the final ground; lay a gravel cushion at the bottom of the foundation pit and compact it with an impact compactor to avoid subsequent settlement.​

II. Core Installation Process​

1. Pedestal Placement: Place the precast concrete pedestal stably in the center of the foundation pit, calibrate the levelness with a level instrument, fill the surrounding area of the pedestal with gravel, and compact it to ensure the pedestal is fixed firmly without looseness.​

2. Surface Box Positioning: Slowly place the ductile iron surface box on the pedestal, calibrate the level again, and adjust the position of the box to align with the direction of the surrounding ground.

3. Pipeline Connection: Connect cables, pipelines, etc., in accordance with design requirements. Install sealing rings at the wire-passing holes for sealing, and wrap the joints between pipelines and the box with waterproof tape for reinforcement; after connection, check that there is no residual debris inside the box and ensure the pipelines are arranged neatly without extrusion.​

4. Backfilling and Leveling: Backfill the surrounding area of the box with graded sand and gravel in layers, compacting while backfilling to avoid hollowing in the backfilled soil; after backfilling, to be flush with the top of the box, lay a cement mortar leveling layer and smooth the surface to be flush with the ground.

5. Cover Installation: Align the cover with the positioning pins of the box, place it stably, and lock the fixing bolts to ensure the cover fits tightly with the box and can be opened and closed flexibly without jamming.​

III. Ground Fixing Specifications

1. Concrete Pedestal Fixing: Fix the bottom of the surface box to the concrete pedestal using embedded bolts. Ensure the embedded depth of the bolts is appropriate, and install lock washers after tightening the nuts; lay rubber gaskets on the contact surface between the pedestal and the box to absorb vibration and improve sealing performance.​

2. Direct Anchoring Fixing: For hard pavements such as asphalt and concrete roads, first drill holes in the ground according to the positions of the fixing holes on the box, insert expansion bolts, align the box with the bolts, place it in position, and tighten the nuts. Control the exposed length of the bolts appropriately, and install decorative covers for protection.​

3. Fixing for Special Scenarios: In soft soil areas, pour reinforced concrete bearing platforms at the bottom of the foundation pit to enhance load-bearing capacity; in waterlogged areas, reserve drainage holes at the bottom of the box and lay a gravel drainage layer around the pedestal to prevent water accumulation inside the box.​

IV. Safety and Acceptance Key Points​

1. During installation, set up warning signs to prevent pedestrians and vehicles from entering the construction area; cut off power and gas supplies when connecting underground pipelines to ensure construction safety.

2. Focus on the following during acceptance: the box is fixed firmly, the top is flush with the ground, the cover has good sealing performance, and the bolts are free from looseness and rust.​

3. After completion, clean up the construction site and repair the road surface around the surface box to ensure the road surface is flat and undamaged.