Air duct insulation construction technology

2022-09-29

Air duct insulation construction technology

1. Process flow of closed-cell rubber-plastic sponge insulation

(1) First, wipe the surface of the air duct clean, wipe off the dust and accumulated water on the surface and let it dry.

(2) Cut the insulation material according to the size of the air duct.

A. When cutting the insulation material, pay attention to make the two long sides clamp the short side, and for the square air duct, make the upper and lower sides clamp the two vertical sides.

B. When cutting the closed-cell rubber-plastic sponge board, a wallpaper knife can be used. The length of the blade should be suitable and keep it sharp. The cutting force should be moderate and uniform, and the section should be flat.

C. For the exposed air ducts in important places such as halls and exhibition halls, in order to ensure that the cutting section is clean and beautiful, a hand-held grinding wheel cutting machine can be used when cutting polyethylene plates.

(3) Brush 401 glue evenly on the outer wall of the tube and the closed-cell rubber-plastic sponge board, wait for a while and let it dry slightly before sticking it on.

(4) Lightly tap the closed-cell rubber-plastic sponge board with a rubber hammer, especially at the four corners of the air duct, to make it stick firmly to the air duct.

(5) Check the appearance of the insulation, and repair it in time if it is inappropriate.

air conditioner duct insulation

2. The thermal insulation process of aluminum foil glass wool board

(1) First, wipe the surface of the air duct clean, wipe off the dust and accumulated water on the surface and let it dry.

(2) Bonding insulation nails

A. The insulation thickness is 40mm, and 60mm long aluminum insulation nails are used.

B. Apply 401 glue on the outer wall of the air duct and the bonding surface of the insulation nail respectively, wait for a while and then stick it on after it is slightly dry.

C. The bonding density of the insulation nails is: 12 pieces/㎡ on the side of the air duct, below, and 9 pieces/㎡ on the top.

D. After 24 hours of sticking the nails, gently pull the insulation nails with force, and only when the insulation nails do not loosen and fall off, can the insulation material be covered.

(3) Cut the aluminum foil glass wool board. Use a hacksaw blade when cutting the board, so that the long side of the insulation material should clamp the short side, and the small piece of insulation material should be used as much as possible on the upper level of the air duct.

(4) Lay aluminum foil glass wool board

A. Gently stick the cut aluminum foil glass wool board on the air duct, push the insulation nails out of the glass wool board with a little force, and fix it with the insulation nail press cover after checking accurately. The gland should be tight and evenly pressed.

B. Bend the heat preservation nail that grows out of the gland and flatten it.

C. When laying insulation nails, the vertical and horizontal joints should be staggered, and the joints between the boards should be tight and smooth.

D. The flanges of the air ducts should be insulated separately and reliably.

E. For the air duct with a large side larger than 1200mm, add a packing tape every 500mm outside the insulation. There are short iron wrapping corners at the junction of the packing belt and the four corners of the air duct.

(5) Stick aluminum foil tape. The seams of the glass wool board should be sealed with aluminum foil tape. The width of the tape is 50mm at the flat seam and 80mm at the corner of the air duct. When sticking the tape, the force should be even and moderate, so that the tape is firmly attached to the aluminum foil glass wool board, and no cracking or falling off occurs.

(6) Winding glass cloth

A. The width of the glass fiber cloth should be 300-500mm, and it should be overlapped by half when winding, so that the surface of the insulation material forms two layers of glass fiber cloth winding.

B. Usually the cut glass fiber cloth has a burr on one side. When using it, pay attention to pressing the burr inside for the sake of beauty.

C. The head of the glass fiber cloth should be firmly fixed with glue.

D. For some elbows, tees, reducing pipes, etc., pay attention to the smoothness of the cloth surface and the appropriate tightness when winding, and glue the cloth to the insulation cotton if necessary.

(7) Brush fire retardant paint. Finally, brush the fireproof paint twice on the glass cloth. When painting, it should be painted along the winding direction of the glass fiber cloth, the coating should be tight and even, and necessary protective measures should be taken to avoid contamination of other parts.

(8) Insulation outsourcing galvanized iron sheet. The air ducts in the air-conditioning room are no longer wrapped with glass cloth after being pasted with aluminum foil tape, but are covered with galvanized iron sheets.

A. Cut the iron sheet according to the size of the air duct after heat preservation, and pay attention to make allowances according to the overlapping method.

B. The iron sheet should be installed from the bottom to the top, and the lap joint should be fixed with self-tapping screws, and the distance between the self-tapping screws is 120mm.

C. Elbow, tee, reducer, etc. should keep their original shape after insulation, and the iron sheet should be installed with an even arc, and the lap joint should be on the same side of the air duct.

D. In order to ensure the smooth appearance of the iron sheet installation, for large-sized air ducts, wooden square nails with the same thickness as the insulation thickness can be used to form a frame, and the iron sheet is fixed on the wooden frame with self-tapping nails.

air duct insulation