Polyurethane Insulation Board Production Line

A Polyurethane Insulation Board Production Line, used to manufacture rigid PIR (Polyisocyanurate) or PUR (Polyurethane) foam insulation panels, commonly known as "sandwich panels" or "continuous panels."

 

These panels are widely used for building insulation (roofs, walls), cold storage, and industrial applications. The core is rigid foam, and the facers are typically aluminum foil, glass felt, paper, or steel sheets.

 

Production Process Overview

The entire process is a continuous, highly automated line that can run 24/7. The key stages are:

 

Facer Unwinding & Pre-heating → Core Foam Pouring → Double-Belt Press → Curing & Cooling → Cutting & Trimming → Stacking & Packaging

 

Key Components of the Production Line

1. Raw Material Handling & Storage

Polyurethane Chemicals: Two primary components are stored in bulk tanks or drums:

 

Polyol Blend: A mixture of polyols, catalysts, blowing agents (e.g., pentane, water, or HFOs), flame retardants, and surfactants.

 

Isocyanate (typically MDI): The reactive component. For PIR boards, a higher ratio of isocyanate is used.

 

Temperature Control Units: Maintain the chemicals at a precise, constant temperature (e.g., 20-25°C) for optimal viscosity and reaction.

 

Facer Rolls: Large rolls of the facing material (e.g., aluminum foil, glass fiber mat) are mounted on decoilers.

 

2. Facer Unwinding & Pre-heating Station

Bottom and Top Decoilers: Unwind the lower and upper facer materials.

 

Alignment Systems (Edge Guiding): Ensure the facers run perfectly centered through the entire line to prevent misalignment.

 

Pre-heating Units: Often use infrared heaters or hot air blowers to warm the facers. This improves the adhesion of the liquid foam and helps control the foam rise.

 

3. Polyurethane Mixing & Pouring Station

This is the heart of the production line where the liquid foam is created.

 

High-Pressure Pouring Machine:

 

Metering Pumps: Extremely precise piston pumps that deliver the polyol and isocyanate at a high pressure and in an exact ratio (critical for consistent foam quality).

 

Mixer Head: A high-pressure impingement mixing head. The two liquid streams collide at high pressure inside the head, creating a homogenous mixture without mechanical stirring. The head is self-cleaning.

 

Pouring Trolley/Traversing System: The mixing head is mounted on a trolley that moves back-and-forth (traverses) across the width of the moving bottom facer. This ensures an even distribution of the liquid foam mixture across the entire panel width.

 

4. The Double-Belt Press (The Forming Tunnel)

This is the most critical and expensive part of the line. It defines the panel's thickness and quality.

 

Synchronized Steel Belts: Two endless, precisely machined, and polished steel belts (top and bottom) form the upper and lower surfaces of the tunnel.

 

Platens: A series of heated plates above and below the belts provide the necessary temperature for the foam to rise and cure.

 

Height Adjustment System: The gap between the top and bottom belts is meticulously controlled to set the final thickness of the insulation board (e.g., from 20mm to 200mm).

 

Tensioning System: Maintains the steel belts flat and taut to ensure a panel with perfectly parallel surfaces.

 

Process: The bottom facer, with the liquid foam poured on it, enters the press. The top facer is laid on top, and the two steel belts contain the rising foam, shaping it into a panel with smooth, consistent surfaces and a controlled density.

 

5. Curing & Cooling Zone

Curing Section: The initial part of the double-belt press is heated (typically with hot oil or electricity) to catalyze the chemical reaction. The foam rises, gels, and cures as it travels through this section.

 

Cooling Section: The latter part of the line often includes a cooling zone (with water-cooled platens or air blowers) to solidify the foam and stabilize the panel before it is cut, preventing post-expansion.

 

6. Cutting & Trimming Station

Longitudinal Side Trimmer: As the continuous panel exits the double-belt press, rotating knives trim the edges to the final precise width and create a clean, straight side.

 

Cross-Cutting Saw: A high-speed saw (oscillating or circular) automatically cuts the continuous panel into pre-set lengths. The cutting is synchronized with the panel's movement for a square cut.

 

7. Stacking & Packaging

Panel Turner/Orienter: Flips the panels if needed for specific stacking patterns (e.g., to create a shiplap joint).

 

Automatic Stacker: Collects the cut panels and stacks them onto pallets in a pre-programmed sequence.

 

Stretch Wrapping Machine: Secures the stacked pallet with plastic film for storage and shipment.

 

Key Technical Considerations

Foam Density: Controlled by the pour quantity and the line speed. Common densities range from 30 kg/m³ to 45 kg/m³ for insulation boards.

 

Thermal Conductivity (Lambda Value): The primary quality metric. A well-run line produces foam with a low, consistent lambda value (e.g., 0.022 - 0.028 W/m·K).

 

Line Speed: Determines production capacity. Speeds can range from 4 to over 20 meters per minute, depending on panel thickness and formulation.

 

Fire Performance: The chemical formulation is critical to achieving fire ratings like Class B, or Class A according to various standards (e.g., EN 13501-1).

 

In summary, a Polyurethane Insulation Board Production Line is a complex integration of chemical processing, precision mechanical engineering, and automated control systems. It transforms liquid chemicals and roll facers into a high-performance, continuous composite material essential for energy-efficient construction.