Tag Archives: Steel fireproof doors with fire-resistant expansion seals

Steel Fireproof Doors with Fire-Resistant Expansion Seals: Technical Specifications

1. Core Fireproofing System

  • Steel Construction:

    • 18-20 gauge (1.0–1.5mm) galvanized steel skins

    • Reinforced lock/hinge zones (3mm steel plates)

  • Fire-Resistant Core:

    • Mineral wool (≥110kg/m³ density)

    • Vermiculite boards (for 120+ min ratings)

    • Ceramic fiber (industrial high-heat applications)

2. Fire-Resistant Expansion Seals

Component Material Activation Temp Expansion Ratio Function
Intumescent Strip Graphite-based 180–200°C 5–10× original size Seals gaps when heated
Cold Smoke Seal EPDM rubber N/A (always active) – Blocks smoke at ambient temps
Thermal Barrier Ceramic fiber tape 300°C+ – Prevents heat transfer

Installation:

  • Continuous 4-sided application (top, sides, threshold)

  • Compressed to 70% of original thickness for proper sealing

3. Fire Test Performance (GB 12955 / EN 1634 / UL 10C)

Rating Duration Max Temp Seal Activation Time
30 min 840°C ≤2 min
60 min 925°C ≤3 min
90 min 980°C ≤5 min
120+ min 1050°C ≤10 min

Pass/Fail Criteria:
✔ No flame penetration
✔ Unexposed side ΔT <140°C
✔ Smoke leakage ≤25m³/h·m²

4. Manufacturing Process (Key Steps)

  1. Steel Cutting & Forming

    • Laser-cut panels with ±0.5mm tolerance

    • Press-brake edges for structural rigidity

  2. Seal Groove Machining

    • CNC-routed channels (6–8mm wide × 4mm deep)

    • Deburred edges to prevent seal damage

  3. Seal Installation

    • High-temp adhesive bonding

    • Compression rollers ensure proper seating

  4. Quality Control

    • Smoke leakage test @ 25Pa pressure

    • Burner test (seal samples exposed to 300°C)

5. Door Types & Configurations

Type Seal System Best For
Standard Fire Door 3-sided intumescent Offices, apartments
Smoke & Fire Door 4-sided intumescent + EPDM Hospitals, stairwells
Industrial Fire Door Ceramic-fiber reinforced Factories, warehouses
Security Fire Door Dual intumescent layers Banks, data centers

6. Installation Requirements

  • Frame Gaps: 3–4mm (sealed with fire-resistant mortar)

  • Hardware:

    • 3+ stainless hinges (melting point >800°C)

    • Self-closing mechanism (NFPA 80 compliant)

  • Threshold Seal: Automatic drop-down or brush-type

7. Maintenance & Inspection

Check Frequency Method
Seal integrity Quarterly Visual + compression test
Hardware function Biannually Operational test
Corrosion Annually Surface inspection

Replacement Triggers:

  • Seal compression recovery <60%

  • Visible cracks/chars on intumescent material

8. Top Global Suppliers

  • Assa Abloy (Pyropanel)

  • Chinsun Fire (GB 12955 certified)

  • UK Fire Doors (BS 476 compliant)

  • VT Industries (UL 10C rated)

9. Cost Factors

  • Basic 60-min door: $300–600

  • High-end 120-min door: $800–1,500

  • Seal upgrades: +15–30% cost

Key Advantages vs. Standard Fire Doors

✔ Faster seal activation (2–5 min vs. 5–10 min)
✔ Superior smoke blocking (meets EN 1634-3 Class Sa)
✔ Longer service life (10–15 years vs. 5–8 years)

For optimal performance:

  • Specify third-party certified seals (UL 2079 / EN 1366-4)

  • Require on-site seal testing during installati

knowledge, News

Essential Role of Fire-Resistant Expansion Seals in Fire Doors

Posted on by Zhang Yulin

Optimizing Fire Safety: The Essential Role of Fire-Resistant Expansion Seals in Chinese Fire Doors Fire doors represent a crucial aspect of passive fire protection systems within buildings, serving to effectively isolate the source of a fire, prevent the spread of flames, and thereby safeguard both lives and property. Among the key components of fire doors […]

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