Tag Archives: Steel fireproof doors

Steel Fireproof Doors: Comprehensive Technical Overview

1. Core Specifications

• Fire Ratings:

  • 30/60/90/120/180 minutes (tested to GB 12955, UL 10C, EN 1634)

  • Must maintain integrity + insulation + smoke blocking

• Standard Sizes:

  • Single leaf: 900-1200mm (W) × 2100-2400mm (H)

  • Double leaf: 1200-1800mm (W) × 2100-2400mm (H)

• Thickness: 45-55mm (standard), up to 70mm (high-security)

• Weight: 50-80kg (30min) to 120-150kg (180min)

2. Material Composition

3. Manufacturing Process

1. Steel Cutting

   • Laser precision cutting (±0.3mm tolerance)

   • Edge deburring (R0.5mm max)

2. Core Assembly

   • Layered structure: Steel → Ceramic mat → Mineral wool → Steel

   • Hydraulic pressing (15kg/cm² @ 150°C for 30min)

3. Sealing System

   • 3-sided continuous intumescent seal

   • Cold smoke gasket (EPDM rubber)

4. Surface Treatment

   • 7-stage pretreatment (degreasing → phosphating → passivation)

   • Electrostatic powder coating (60-80μm thickness)

4. Performance Testing

• Fire Test: ISO 834 time-temperature curve

  • 30min door must withstand 840°C

  • 90min door must withstand 980°C

• Hose Stream Test: Immediate water impact after fire exposure

• Cyclic Test: 100,000 open/close cycles

5. Certification Marks

• China: CCCF + GB 12955 label

• EU: CE + EN 1634 classification

• North America: UL Listed + hour rating

• Middle East: ESMA/DCL approval

6. Installation Requirements

• Frame Anchoring: M10 fire-rated expansion bolts @ 600mm spacing

• Clearances:

  • Top/sides: 3±0.5mm

  • Threshold: 8-10mm (with automatic drop seal)

• Hardware:

  • Minimum 3 hinges (304 stainless steel)

  • Self-closing device (force 70-110N)

7. Maintenance Protocol

8. Cost Factors

• Material (60%): Steel grade (SGCC vs DX51D), core type

• Certification (20%): Local vs international approvals

• Features (20%): Glazing, security upgrades, smart systems

9. Industry Trends

• Smart Integration: IoT sensors for real-time monitoring

• Hybrid Materials: Aramid fiber reinforcement

• Green Manufacturing: Chrome-free pretreatment processes

10. Common Failure Modes

1. Seal Degradation: UV exposure → replacement every 5-7 years

2. Hinge Wear: Lubrication required every 50,000 cycles

3. Corrosion: Coastal areas need 316 stainless hardware

This specification meets the most stringent global requirements for life-safety applications. For specialized environments (chemical plants, data centers), additional protections like acid-resistant coatings or EMI shielding may be incorporated.