How to use polyurethane hard foam insulation composite board

Polyurethane hard foam insulation composite board (PU hard foam composite board) is a high-efficiency insulation material with polyurethane hard foam as the core material and composite metal or non-metallic surface materials on both sides (such as color steel plates, aluminum foil, cement fiberboard, etc.), which is widely used in exterior walls, roofs, cold storages, pipelines and other scenarios. The usage method needs to be combined with design specifications, construction technology and safety requirements. The following is a detailed description from four stages: selection preparation, construction process, key node control, and acceptance and maintenance:

1. Selection and preliminary preparation

1. Select the plate type according to the scene

Building exterior walls: Metal-surface polyurethane composite panels (such as color steel sandwich panels) are preferred, with a thickness of the surface material ≥0.5mm, a core material density ≥35kg/m³, and a fire resistance level of B1 (flammable retardant) or A (not combustible, flame retardant is required).

Cold storage insulation: double-sided stainless steel or aluminum foil composite panels are used, the core density is ≥40kg/m³, the closed porosity is ≥95%, and the dimensional stability is ≤1% under low temperature environment (-40℃ to +80℃).

Roof waterproof and thermal insulation: Choose polyurethane composite panel with self-adhesive layer, the surface material is high-density cement fiberboard or rust-proof aluminum panel, and the core material compressive strength is ≥200kPa to avoid roof trampling and deformation.

2. Design parameter confirmation

Thickness calculation: According to the 'Civil Building Thermal Design Code' (GB 50176), calculate the required insulation layer thickness. For example, when the heat transfer coefficient of exterior walls in Beijing is K≤0.5W/(m²·K), the thickness of the polyurethane composite plate must be ≥80mm.

Connection method: clarify the fixing method of the plate and main structure (such as anchor bolt fixing, hooking, and bonding). Cold storage needs to use broken bridge anchor bolts (avoid cold bridges).

Fireproof isolation belt: Each floor of the exterior wall of high-rise buildings is equipped with a 300mm wide Class A fireproof material (such as rock wool) isolation belt to prevent the spread of fire.

3. On-site condition inspection

Base treatment: The flatness error of the wall base is ≤3mm/2m, and there is no oil stain or dust; the roof base needs to be a waterproof leveling layer with a slope of ≥2%.

Environmental requirements: Construction temperature ≥5℃, humidity ≤85%, wind force ≤5 (avoid the board blowing off or the bonding is not firm).

2. Standardized construction process

1. Transportation and stacking of plates

Transportation protection: Use a special bracket to fix the board to avoid extrusion and deformation; it is necessary to cover the rainproof cloth in rainy and snowy weather.

Stacking rules: The indoor stacking height is ≤1.5m, the bottom is cushioned with wood (spacing ≤1m), and stay away from fire sources and corrosive substances.

2. Installation steps

(1) Exterior wall installation (taking anchor bolt fixation as an example)

Positioning of the elastic line: According to the design drawings, the plate installation control line is ejected on the base layer, with a spacing error of ≤2mm.

Installation start plate: Start from the corner of the wall or door and window openings, fix the plate to the keel with self-tapping screws, with the spacing between the screws ≤300mm (≥20mm from the edge of the plate).

Plate seam treatment: Qikou splicing: Use male and female slots to plug in, the gap is ≤3mm, and it is filled with polyurethane foam glue.

Flat seam splicing: PE foam rod is embedded in the gap, weather-resistant sealant (such as silicone glue) is applied to the outside, and the glue seam width is 5-8mm.

Angle treatment: The male corner is wrapped with aluminum alloy corner guard strips, the female corner is filled with polyurethane mud, and the surface flatness error is ≤2mm.

(2) Roof installation (taking the hooking type as an example)

Installation of pendants: Weld the L-shaped pendants on the roof purlins, with a spacing of ≤600mm. The height of the pendants must consider the roof drainage slope.

Plate hoisting: Use a special spreader to lift the board to the roof and slowly place it on the pendant to avoid impact.

Fixing and sealing: Use self-tapping screws to fix the plate and the hanging parts, apply sealant to the screw head; cover the seams with T-shaped aluminum alloy strips, and seal them with glue on both sides of the strips.

(3) Cold storage installation (taking double-sided stainless steel plate as an example)

Library panel splicing: adopts convex groove occlusion structure, the gap is filled with polyurethane on-site foaming, and the foaming density is ≥60kg/m³.

Ground treatment: A 10mm thick rubber pad is laid at the connection between the warehouse board and the ground to prevent cold bridges; the periphery of the warehouse door is closed with a polyurethane sealing strip.

Pipe pass through the wall: The gap between the pipe and the warehouse plate is filled with polyurethane foam glue, the outside is protected by stainless steel casing, and the casing and pipe are filled with insulation cotton.

3. Quality control of key nodes

1. Fire safety

Electric welding operations: No storing of plates within 3m of the construction area and equipped with fire extinguishers; check whether there is a risk of ignition in the surrounding area after welding.

Electrical circuits: Temporary power lines need to be protected by metal pipes to avoid fires caused by aging of the lines.

2. Moisture-proof treatment

At the bottom of the exterior wall: Set a 300mm high concrete waterproof ridge at the foot to prevent rainwater from pouring back.

Roof gutter: Waterproof rolls are laid in the gutter, and the rolls are turned up to the inner side of the roof panel ≥250mm, and fixed with a pressing strip.

3. Wind pressure resistance design

High-rise buildings: Each floor is equipped with horizontal horizontal support, with a spacing of ≤6m; the pull-out resistance of the plate and the main structure is ≥0.6kN/piece.

Coastal areas: Increase the number of anchor bolts (spacing ≤200mm), and reinforce them with stainless steel fasteners at the joints of the plate.

4. Acceptance and maintenance

1. Construction acceptance standards

Appearance inspection: The plate is not damaged or deformed, the seams are compact and hollow, and the color is uniform and consistent.

Performance detection: Insulation performance: Use the heat flow meter method to detect the heat transfer coefficient, with an error of ≤5%.

Airtightness: Use the blower method to detect, the overall airtightness of the building is ≤1.5 times/h (@50Pa).

Fire resistance: Pick the plate for combustion test, oxygen index ≥26%, smoke density level ≤75.

2. Post-maintenance points

Regular inspection: Check whether the sealant of the plate joints is cracked and whether the anchor bolt is loose every six months.

Cleaning and maintenance: Use a soft cloth to wipe the surface of the board to avoid using corrosive cleaners; apply anti-rust paint to the metal surface every 2 years.

Local repair: If the board is found to be bulging or falling off, the peripheral sealant needs to be removed, foam and fill it again and seal it.