Sandwich Panel PU

Product Introduction

Polyurethane sandwich panels are a high-performance building material that consists of two layers of metal panels (usually color-coated steel plates, aluminum plates or stainless steel plates) and a polyurethane foam core in the middle to form a "sandwich" structure. The polyurethane core has excellent thermal insulation properties, and is lightweight, high-strength and fireproof, making it widely used in the construction field. This type of panel not only has good thermal insulation and sound insulation effects, but also has excellent waterproof and corrosion resistance, making it suitable for a variety of harsh environmental conditions.

Product Specifications

Polyurethane (PU) sandwich panels are widely recognized in the construction industry for their superior thermal insulation, structural integrity, and lightweight composition. Engineered as a composite of metal facings and a rigid PU foam core, these panels are a go-to solution for cold storage, cleanrooms, prefabricated buildings, and industrial enclosures.

This article provides a comprehensive technical overview, including materials, manufacturing methods, standards compliance, application insights, and buyer FAQs—designed to help contractors, developers, and importers make informed decisions.

Table of Contents

1. What Is a Sandwich Panel PU?

2. Core Materials and Surface Options

3. Technical Specifications and Performance Metrics

4. Manufacturing Process Overview

5. Industry Standards and Compliance

6. Applications and Engineering Benefits

7. Installation Guidelines and Safety Considerations

8. Frequently Asked Questions (FAQs)

9. Conclusion and Call to Action

1. What Is a Sandwich Panel PU?

A PU sandwich panel is a three-layer construction material consisting of:

• External Face: Color-coated steel, stainless steel, or aluminum

• Core Layer: Rigid polyurethane (PU) foam insulation

• Internal Face: Same or different metal cladding as the external layer

PU foam is a closed-cell, high-density insulation material offering superior R-values, moisture resistance, and compressive strength, making the panel ideal for both thermal and structural roles.

2. Core Materials and Surface Options

• PUR (Polyurethane): Lower cost, R-value ~0.022–0.024 W/m·K

• PIR (Polyisocyanurate): Higher fire resistance, slightly better R-value (~0.020–0.023 W/m·K)

3. Technical Specifications and Performance Metrics

• Cam-lock or tongue & groove edge connections

• Enhanced airtightness and structural locking strength

4. Manufacturing Process Overview

1. Material Preparation

• Galvanized or pre-painted coils are loaded onto decoilers.

2. Forming and Foaming

• Panels pass through roll forming machines to create desired profiles.

• Simultaneously, PU foam is injected (via high-pressure foaming machines) between metal facings.

3. Curing and Cutting

• Cured at ambient or elevated temperatures for 30–60s.

• Panels are precision-cut to specified lengths.

4. Quality Control

• Panels are tested for:

• Dimensional accuracy

• Foam density & adhesion

• Thermal conductivity

• Surface finish and flatness

5. Industry Standards and Compliance

6. Applications and Engineering Benefits

6.1 Common Applications:

• Cold storage rooms & refrigerated warehouses

• Clean rooms (pharmaceutical, microelectronics)

• Industrial cladding & partition walls

• Modular homes & prefabricated buildings

• Agricultural buildings (livestock enclosures, poultry houses)

6.2 Engineering Advantages:

• Superior thermal insulation (up to 40% better than EPS panels)

• Quick installation and labor savings

• High strength-to-weight ratio

• Minimal thermal bridging

• Fire resistance (especially with PIR core)

• Excellent resistance to mold, mildew, and corrosion

7. Installation Guidelines and Safety Considerations

Substructure Requirements:

• Steel frames or reinforced concrete structures

• Panels fixed using self-tapping screws and EPDM washers

Sealing and Finishing:

• Silicone or PU sealants ensure weatherproof joints

• Flashing and trims for corners, edges, and wall-roof transitions

Handling & Storage:

• Store panels horizontally on level surfaces

• Use lifting slings with edge protectors

• Avoid prolonged UV exposure before installation

Safety Note:

• Wear gloves and safety gear; foam offcuts may contain MDI particles

8. Frequently Asked Questions (FAQs)

Q1: What’s the lifespan of PU sandwich panels?
Typically 25–35 years with proper installation and maintenance.

Q2: Are PU panels fireproof?
Standard PU (PUR) is fire-retardant (B2/B3). PIR foam offers enhanced fire resistance (B-s1,d0). Always request fire certificates.

Q3: Can PU panels be used for roofing?
Yes. Panels with corrugated profiles and appropriate slopes (≥3%) are suitable for roofing applications.

Q4: How do PU panels compare with rock wool panels?

• PU: Better thermal insulation, lighter, lower fire rating

• Rock wool: Non-combustible, higher fire safety, heavier

Q5: Is PU foam eco-friendly?
PU production uses petrochemicals but panels are energy-efficient and recyclable. Look for zero-CFC and HFC-free foaming agents.

9. Conclusion and Professional Call to Action

PU sandwich panels represent a cost-effective, high-performance solution for modern construction needs. With outstanding thermal performance, structural integrity, and compliance with international standards, they’re the ideal choice for energy-efficient buildings, cold chain infrastructure, and prefab solutions.