Outer Skin Materials
The most common choice is 0.8–1.2 mm fiberglass (FRP), though galvanized steel or aluminum alloys are also used. Aluminum alloys-specifically the 6005A and 6061 grades-are widely utilized due to their combination of lightweight properties, corrosion resistance, and excellent impact strength.
Core Insulation Materials
Polyurethane (PU) foam is the most frequently used material; it offers excellent thermal insulation with a thermal conductivity of ≤0.022 W/(m·K). Extruded polystyrene (XPS) board is another option; it is lighter and more cost-effective, making it suitable for short- to medium-distance transport.
Inner Skin Materials
Food-grade fiberglass or 304 stainless steel is typically used. These materials feature smooth, easy-to-clean surfaces that meet hygiene standards for transporting food and pharmaceuticals. Some models also incorporate aluminum alloy ventilation channels to optimize cold air circulation.