Technical Summary: PU (Polyurethane) panels manufactured on a continuous high-pressure foaming line at Tan Long factory (Duc Hoa 1 IP, Long An). Featuring an ultra-low thermal conductivity λ = 0.018 – 0.020 W/m.K and a closed-cell ratio exceeding 95%, this is the indispensable insulation material for seafood cold storage, international cold chain logistics hubs, and IQF quick-freezing tunnels requiring deep sub-zero temperatures from -20°C down to -50°C.
1. Engineering Specifications & Composition of PU Sandwich Panels
In industrial cold storage systems, maintaining stable temperature margins with minimum energy consumption depends 70% on the thermal enclosure envelope quality. PU sandwich panels (Polyurethane Foam Sandwich Panels) are engineered with 3 durable physicochemical bonded layers:
- Core Insulation Layer (Core Foam): High-pressure injected Polyol and Isocyanate compound, uniformly expanded into a micro-cellular closed structure with standard compression density of 40 – 42 kg/m³. Due to dense molecular structure without open air voids, the PU core completely halts internal air convection and moisture ingress.
- Double Protective Facing Sheets: Double-sided Zincalume/Colorbond steel imported from BlueScope Steel (0.45mm – 0.60mm thickness) coated with food-safe antibacterial Clean Colorbond paint, or AISI 304 stainless steel (ribbed or flat, 0.5mm – 0.8mm) resistant to marine salt spray and aggressive chemical washdowns.
- Eccentric Camlock Fasteners: Galvanized steel alloy latches cast directly into the PU foam edge during precision mold pressing. During jobsite installation, technicians use a hexagonal key to torque the interlocking male-female latch, drawing panel joints tightly together with mechanical clamping force up to 200 kg/latch, completely eliminating thermal bridges.
Continuous high-pressure foaming line producing pre-cast Camlock PU sandwich panels at Tan Long Refrigeration factory.
2. Detailed Technical Specifications Matrix of Tan Long PU Panels
All PU panel products dispatched from Tan Long facility undergo rigorous quality verification complying with ASTM C518, ISO 8301, and TCVN 9313:2012 standards:
| Technical Specification | Standard Parameters | Test Method |
|---|---|---|
| PU Foam Core Density | 40 – 42 kg/m³ (± 2 kg/m³) | ASTM D1622 |
| Thermal Conductivity (K-factor / λ) | 0.018 – 0.020 W/m.K at 20°C | ASTM C518 / ISO 8301 |
| Closed Cell Content | ≥ 95% by volume | ASTM D2856 |
| Compressive Strength | ≥ 0.20 – 0.25 N/mm² (at 10% deformation) | ASTM D1621 |
| Surface Adhesion Strength | ≥ 0.15 N/mm² (foam cohesion failure before sheet separation) | DIN 53455 |
| Water Absorption Rate | ≤ 1.0 – 1.5% by volume after 24h water immersion | ASTM D2842 |
| Water Vapor Permeability | ≤ 1.8 – 2.0 ng/Pa.s.m² | ASTM E96 |
| Edge Interlocking System | Tongue & groove + Pre-cast internal Camlock latches | Tan Long Proprietary Specification |
| Standard Width (W) | 1,000mm – 1,150mm (effective width) | Standard design module |
| Panel Length (L) | Custom cut to span dimensions (up to 15,000mm) | Per shop drawing specification |
| Core Thickness | 50mm, 75mm, 100mm, 125mm, 150mm, 175mm, 200mm | Supporting +10°C down to -50°C |
3. Guide to Selecting PU Panel Thickness Based on Operating Temperature
Selecting an improper panel thickness is the #1 cause of wall sweating, surface condensation, floor frost heave, and surging electric bills. Below is the technical recommendation matrix from Tan Long senior refrigeration engineers:
- Thickness 50mm – 75mm (Temperature +5°C to +15°C): Ideal for buffer rooms (anterooms), import/export loading docks, seafood grading and packaging areas, seed storage, and pharmaceutical cooling rooms.
- Thickness 100mm (Temperature 0°C to -5°C): Engineered for agricultural cold storage, fruits, vegetables, fresh meat holding rooms, and cold beverage storage.
- Thickness 125mm – 150mm (Temperature -18°C to -25°C): Gold standard specification for seafood export cold storage (shrimp, pangasius, squid), frozen meat warehousing, and cold chain logistics centers (such as Kido Foods Ice Cream Warehousing or Lineage Logistics).
- Thickness 175mm – 200mm (Temperature -35°C to -50°C): Mandatory requirement for deep blast holding rooms, sashimi tuna storage for Japanese export (Frescol Tuna Project -60°C), blast freezing chambers, and enclosures for IQF continuous freezing tunnels.
4. Comparative Analysis: PU vs. EPS vs. PIR Panels
To help investors balance capital expenditure against long-term 15-20 year thermal efficiency, Tan Long provides an objective side-by-side comparison matrix:
| Evaluation Metric | Panel PU (Polyurethane) | Panel EPS (Polystyrene) | Panel PIR (Polyisocyanurate) |
|---|---|---|---|
| Thermal Conductivity (λ) | 0.019 W/m.K (Very Good) | 0.038 W/m.K (Average) | 0.018 W/m.K (Outstanding) |
| Fire Performance | Self-extinguishing away from flame (B3) | Combustible, prone to rapid fire spread | Flame spread resistance B1/B2, PIR FM Approved |
| Joint Structural Strength | Pre-cast Camlock latch (extremely rigid) | Z-lock or simple tongue & groove | Camlock latch or deep airtight interlocking groove |
| Moisture Resistance | ≥ 95% closed cell (zero moisture accumulation) | Open-bead structure absorbs water over time | ≥ 97% closed cell (impervious to moisture) |
| Thermal Lifespan | 15 – 25 years consistent insulation value | 5 – 8 years (rapid performance degradation) | 20 – 30 years long-term stability |
| Investment Cost | Medium – High (Optimal long-term ROI) | Lowest (Suitable for short-term cool rooms) | Highest (Mandatory for high-end FDI food export facilities) |
| Detailed Reference Page | View PU Panel Details | View EPS Panel Details | View Fireproof PIR Panel Details |
5. Engineering Installation Protocols for HACCP & FDA Compliance
Even a premium panel installed with improper workmanship becomes a massive thermal leakage hazard. At Tan Long, cold room envelope installation strictly adheres to ASHRAE international refrigeration guidelines:
- 1. Subfloor Preparation & Underfloor Ventilation: For sub-zero cold rooms, natural convective ventilation ducts or electric subfloor heating mats must be installed to prevent frost heave from destroying structural foundation slabs.
- 2. Continuous Neutral Silicone & PU Expanding Foam Application: Prior to locking Camlock fasteners, twin beads of low-temperature neutral sealant are extruded along the male-female tongue and groove. Once torqued, perimeter joints are backfilled with polyurethane foam to ensure zero air gaps.
- 3. R50 Curved Sanitary Aluminum Profiles: All internal intersections between wall-ceiling and wall-floor are trimmed with specialized R50 sanitary radius aluminum coving. This prevents bacterial and mold accumulation while enabling high-pressure washdown in compliance with HACCP and US FDA standards.
- 4. Integrated Thermal Break Cold Room Doors: Doorways are the most vulnerable thermal breach points. Tan Long incorporates T-Light sliding cold room doors with frame heater wire and high-speed PVC spiral roll-up doors at dock levelers to eliminate convective refrigeration loss.
6. Latest 2026 Cold Storage PU Panel Price Quotation
PU panel costs fluctuate depending on global BlueScope steel coil prices and Isocyanate/Polyol chemical raw material indices. To assist investors in preliminary project budgeting, Tan Long transparently publishes ex-factory price guidelines from our Duc Hoa manufacturing plant:
- PU Panel 50mm (Density 40kg/m³, 0.45mm steel): From 420.000 – 480.000 VND/m²
- PU Panel 75mm (Density 40kg/m³, 0.45mm steel): From 530.000 – 590.000 VND/m²
- PU Panel 100mm (Pre-cast Camlock, 0.45mm steel): From 650.000 – 720.000 VND/m²
- PU Panel 125mm (Pre-cast Camlock, for -20°C freezers): From 780.000 – 860.000 VND/m²
- PU Panel 150mm (Pre-cast Camlock, for -25°C to -30°C storage): From 890.000 – 980.000 VND/m²
- PU Panel 200mm (Pre-cast Camlock, for -45°C deep blast rooms): From 1.150.000 – 1.300.000 VND/m²
- Note: The unit prices above apply to standard pre-painted Zincalume steel skins. If seafood-grade AISI 304 stainless steel is required, please add 250,000 – 380,000 VND/m². For comprehensive turnkey project budgeting covering both thermal envelopes and refrigeration machinery racks, please consult our 2026 Turnkey Cold Storage Price Quotation.
In-Depth Technical FAQs on Thermal PU Panels
1. Can Camlock PU panels be dismantled and relocated to another site?
Yes. This is the paramount advantage of pre-cast Camlock PU sandwich panels. When expanding warehouse area or relocating factory premises, engineers simply use a hex key to reverse-turn the cam locks, separating each panel intact without foam degradation or skin deformation, achieving a reusability rate exceeding 95%.
2. What steel facing does Tan Long use, and will it rust in saline marine environments?
Tan Long utilizes BlueScope Steel Colorbond For Cleanrooms or imported 304 BA/2B stainless steel. The steel is coated with an aluminum-zinc alloy protective layer combined with a 25-micron food-grade antimicrobial finish, offering exceptional corrosion resistance in humid, high-salinity seafood processing facilities.
3. Why must a -25°C deep frozen cold storage use PU panels rather than cheaper EPS panels?
EPS panels feature an open-bead structure with a thermal conductivity twice that of PU (0.038 vs. 0.019 W/m.K). Under a 55°C to 65°C delta T against ambient outdoor temperatures, partial water vapor pressure drives moisture through EPS beads where it freezes internally. This permanently degrades insulation within 1-2 years and forces refrigeration compressors into severe overload, adding up to 40% in recurring electric utility costs.
4. Will Tan Long Camlock latches rust or break after years of sub-zero operation?
Tan Long Camlock latches are high-strength die-cast steel alloys with electrolytic galvanization, engineered for tension loads exceeding 200kg. Because they are hermetically embedded inside the 42kg/m³ closed-cell PU foam matrix away from air and moisture, the latches will never corrode or degrade throughout the cold storage facility 20+ year design life.
5. What is the manufacturing lead time for a 1,000m² PU panel order at the Duc Hoa factory?
With automated continuous production lines capable of 3,000m²/day at the Duc Hoa 1 Industrial Park factory, a standard 1,000m² Camlock PU panel order is completely fabricated and cured within 2 to 4 business days, ready for expedited delivery via Tan Long dedicated transport fleet.
6. How can investors distinguish genuine 40-42kg/m³ high-density PU panels from cheap adulterated foam?
Standard high-density PU features a uniform light yellow hue, a smooth cut cross-section with microscopic closed air cells, and high compressive elasticity that resists indentation under strong finger pressure. Poor quality panels often exhibit blotchy dark patches, brittle crumbly foam, and an actual density of only 32-35kg/m³, causing severe wall condensation and frost development shortly after commissioning.
7. Does Tan Long provide detailed 3D shop drawings for panel layout and cutting plans?
Yes. Upon contract confirmation for materials or turnkey EPC execution, Tan Long engineering design division generates comprehensive 3D shop drawings for every wall, ceiling, floor panel, HVAC penetration cutout, door opening, and aluminum flashing schedule. This ensures zero waste and flawless jobsite erection without haphazard field adjustments.
8. What is the warranty policy for Tan Long PU sandwich panels?
All PU panels manufactured at Tan Long factory are backed by an official 24-month comprehensive warranty covering thermal performance, structural integrity, and skin delamination. We provide complimentary technical inspection throughout the warranty term and lifetime spare material support.
