Installation process of access door.

Preparation of the hole: clean up the floating dust of the impurities at the hole, check the dimensional deviation (5 mm is allowed), and chisel or repair the deviation; The edge of the concrete hole is roughened and coated with interfacial agent.

Door frame positioning: put the door frame, adjust the verticality (deviation ≤1.5mm/m) and elevation (3 mm), and temporarily fix it with a wooden wedge to ensure that the gap between the door frame and the wall is even (8-10mm).

Door frame fixing: drill holes in the preset bolt holes and implant M10 expansion bolts, with the torque controlled at 35-40N m and no less than 3 fixing points on each side. Installation and debugging of door leaves: install hinges (thickness ≥3mm) to ensure the opening angle ≥ 90; Debugging the door closer, no impact from 90 to closing time of 6-8 seconds; The fire lock has flexible locking tongue and smooth key insertion and removal.

Gap sealing: the gap between the door frame and the wall is filled with fireproof rock wool, and the surface is coated with expanded fireproof sealant (thickness ≥ 5 mm); After the welding parts are polished and derusted, apply anti-corrosion primer and topcoat.