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Insulation construction technology of air duct and components

Insulation construction technology of air duct and components


Insulation construction technology of air duct and components


First: Preparation

1. Confirm that the on-site civil structure has been completed and that there is no large amount of water used for construction.

2. Confirm that the professional construction of pipes, electrical, fire protection, etc. above the air duct is basically completed, so as to avoid a large number of cross-operations from damaging the thermal insulation.

3. After the installation of the air duct system is completed, the quality of the self-inspection is qualified, and the inspection report is submitted to the supervisor, and the inspection record of the concealed project is completed.

4. The air leakage test of the air-conditioning system is qualified.

5. All kinds of materials required for construction have arrived, and their material certificates and qualification certificates are complete, and all indicators meet the design requirements.

6. Ladders, shelves, lighting fixtures, etc. used for construction are complete and reliable after inspection.


Second: the process overview

1. In the project, the insulation material is generally in accordance with the design requirements. For clean air ducts, generally use non-combustible closed-cell rubber-plastic sponge insulation materials, and for exhaust air ducts generally use non-combustible aluminum foil glass wool boards. The process is as follows:

Picking cutting insulation material gluing (sticking nails) and laying insulation material inspection

2. The specifications of thermal insulation materials should meet the design requirements, and have quality certification documents such as certificate of conformity.

3. The cutting should be accurate. The cutting surface should be flush, and when cutting the material, the overlap of the horizontal and vertical surfaces should be placed on the beam with both ends of the short surface.

4. The thickness of the glue should be uniform, and it should not accumulate or flow.

5. The thermal insulation material is covered and bonded tightly, without hollowing, and the seams are tight and not exposed.


Third: 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.

(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 then glue it on after it is slightly dry.

(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.


2. 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

(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

(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 surface of the aluminum foil glass wool board, and no cracking or falling off occurs.

(6) Winding glass fiber cloth

(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) The thermal insulation is covered with 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.


Fourth: Quality standard

1. Guarantee project

(1) The material, specification and fire performance of the thermal insulation material must meet the design and fire protection requirements. The certificate of conformity to check the material.

(2) The joints between the air duct and the equipment, as well as the parts that are prone to condensate water, must be well insulated, tight and without gaps.

2. Basic items

(1) The insulation of the polyethylene board should meet the following requirements: the paste is firm, the joints are filled with glue and filled with glue, and the joints are even and neat, flat and consistent, and the longitudinal joints are staggered.

(2) The insulation of the glass wool board should be close to the surface of the air duct, tightly wrapped, and moderately tight.

(3) The protective layer of glass fiber cloth should be tight and moderate, the overlap width should be uniform, and it should be flat and beautiful.

(4) The protection of galvanized iron sheet should be lapped along the direction of water flow, with appropriate width, smooth interface, firm fixation, uniform lap width and beautiful appearance.

(5) After the air valve is insulated, it should not hinder the operation, and the opening and closing signs are clear and clear.

3. Allowable deviation items


Fifth: Finished product protection

(1) Reliable measures must be taken for the site where thermal insulation materials are stacked, and it should be placed indoors and overhead with the ground.

(2) Galvanized iron wire, glass fiber cloth, thermal insulation nails and thermal insulation glue materials should be stored in the warehouse, and they should be collected as needed, and returned to the warehouse in time after work.

(3) Pay attention to inspection during the pressure test of the pipeline to prevent a large amount of water leakage and soaking for heat preservation.

(4) It is strictly forbidden to walk on the air duct after insulation.


Sixth: Issues that should be paid attention to

(1) All processes of thermal insulation must be inspected, and the procedures must be completed. Before thermal insulation and before wrapping glass fiber cloth, there should be hidden inspections and records.

(2) When sticking insulation nails, the indoor temperature should be properly considered to give sufficient curing time. When the insulation nails are not firmly glued, avoid bumping to prevent them from falling off.

(3) The head shake of the glass fiber cloth must be firmly adhered to prevent loosening.

(4) Reliable measures should be taken when applying fire retardant paint to avoid contamination of walls and floors.

air duct

glass fiber


thermal insulation

aluminum foil

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