Modern main door hinge with fire rated

A full mortise hinge is a heavy-duty architectural butt hinge crafted from stainless steel, designed specifically for commercial, industrial, and institutional applications. Its fully recessed leaves fit seamlessly into machined mortises on door edges and frames. This creates a flush, protrusion-free finish—eliminating the bulk of surface-mounted hinges for a sleek, professional look. Constructed with stainless steel and integrated ball bearings, it ensures smooth, low-friction operation even in high-traffic environments. UL-listed models offer 3-hour fire resistance certification, fully complying with building code requirements for fire-rated door assemblies. Ideal for exterior commercial/industrial doors, heavy solid wood/metal interior doors, 3-hour fire-rated systems, and high-traffic institutional projects in schools, hospitals, and industrial facilities.

Technical Specifications

Product Images and Videos

Product Features & Advantages

• UL 3-Hour Fire Protection: This fire rated hinge is designed to maintain structural integrity for up to three hours under extreme fire conditions, withstanding temperatures of approximately 1700°F (927°C). Tested and listed for UL 3-hour fire protection, it plays a critical role in maintaining the fire barrier performance of fire-rated doors and assemblies. By preventing premature door collapse or misalignment during a fire, the hinge supports safe evacuation routes and helps limit fire and smoke spread in compliance with NFPA and EN 1634 fire safety requirements.
• 2BB Ball Bearing System: Equipped with a double ball bearing (2BB) mechanism, the hinge significantly reduces friction compared with traditional plain-bearing hinges. This design allows heavy fire doors to operate smoothly and quietly even under high-frequency daily use. Reduced friction not only improves user experience but also minimizes metal wear, extending the hinge service life by up to 50% and lowering long-term maintenance costs in commercial and institutional buildings.
• Full Mortise Design: The full mortise configuration allows both hinge leaves to be recessed flush into the door edge and frame, creating a clean, modern appearance while enhancing structural stability. This concealed installation improves resistance to tampering and forced impact, which is especially important for fire-rated and security-sensitive doors. The flush alignment also ensures seamless compatibility with contemporary door handles and door knobs without visual or functional interference.
• Stainless Steel Durability: Manufactured from high-quality stainless steel, the hinge is available in SUS304 for humid indoor environments and SUS316 for coastal or high-corrosion areas. These materials provide excellent resistance to rust, oxidation, and chemical exposure, ensuring reliable performance in bathrooms, service corridors, and covered outdoor entryways. The inherent strength of stainless steel also supports heavy door loads without deformation over time.
• System Compatibility: This fire rated hinge is engineered to work seamlessly with other essential door hardware components, including door closers, panic exit devices, and fire-rated door seals. Such compatibility simplifies hardware specification and procurement, allowing contractors and project managers to source a complete, compliant door hardware system from a single supplier, reducing coordination risks and installation errors.

Application Scenarios

• Hospital Corridors & Patient Areas (Fire Safety & Smooth Operation): In healthcare settings, maintaining clear, safe evacuation routes during emergencies is non-negotiable, while ensuring smooth daily workflows is equally critical. Fire-rated door hinges are engineered to keep fire doors fully functional and compliant with life-safety codes even under extreme heat, preventing fire and smoke spread. Meanwhile, the 2BB ball bearing mechanism ensures doors open and close smoothly, quietly, and consistently—even with frequent passage of hospital beds, trolleys, and staff. This dual performance directly supports both regulatory fire safety requirements and uninterrupted daily care operations, making it a reliable choice for healthcare facility managers.
• Office Buildings & Commercial Spaces (High-Traffic Performance):Office environments see constant door use in corridors, meeting rooms, and shared amenities, putting hinges to the test daily. The 2BB ball bearing design delivers ultra-low friction operation, drastically reducing door noise, hinge wear, and the need for frequent maintenance—critical for preserving a productive, professional workplace. Its long-lasting performance minimizes downtime and replacement costs, making it a cost-effective, high-value solution for commercial property owners and facility managers prioritizing durability and user experience.
• Residential Entry Doors & Multi-Unit Buildings (Safety with Durability):For apartment complexes, condominiums, and residential entryways, fire safety is a top priority, without sacrificing aesthetic appeal or durability. Fire-rated door hinges meet strict life-safety standards to protect occupants during emergencies, while their stainless steel construction offers robust corrosion resistance and structural strength. This ensures hinges maintain reliable performance through years of daily use, even in high-moisture or coastal environments. Balancing safety, longevity, and a clean, unobtrusive look, this solution is ideal for developers and homeowners seeking both compliance and peace of mind.

Certifications and Compliance

• UL Listing: The hinge is UL listed with a 3-hour fire rating, ensuring proven performance under extreme fire conditions. Compliance with ANSI/BHMA standards further confirms its suitability for demanding commercial applications across global markets.
• ISO 9001: Manufacturing is carried out under an ISO 9001 certified quality management system, ensuring consistent production processes, traceability, and product reliability from batch to batch.
• SGS Audited: The factory is audited by SGS, verifying ethical manufacturing practices, production capability, and quality control procedures, which enhances buyer confidence in long-term cooperation.

Customization Options

• Material Upgrades: For projects in aggressive environments such as swimming pool facilities or coastal regions, SUS316 stainless steel is available to provide enhanced corrosion resistance and longer service life.
• Finish Customization: A variety of finishes, including PVD black and gold, can be supplied to visually match door handles, smart locks, and other architectural hardware, ensuring design consistency throughout the project.
• Size Modifications: For extra-heavy or oversized fire doors, thicker gauge options and reinforced designs can be customized to meet higher load and durability requirements.
• OEM/ODM: Private labeling, customized packaging, and 3D model development are available to support brand owners, distributors, and large-scale projects requiring tailored solutions.

Production Process & Quality Control

1. Material Testing: Raw stainless steel materials undergo spectroscopic analysis to verify chemical composition and ensure the required purity levels for strength, corrosion resistance, and fire performance.
2. CNC Machining: Advanced CNC machining ensures high-precision component production with tolerances controlled within ±0.01 mm, allowing perfect fitment of the 2BB ball bearing system.
3. Heat Treatment: Components are heat-treated at temperatures up to 1050°C to enhance mechanical strength and stability, enabling the hinge to meet strict UL 3-hour fire rating requirements.
4. Performance Testing: Sample products are subjected to comprehensive testing, including 3-hour fire exposure, 100,000-cycle bearing endurance tests, and load testing up to 200 lbs, ensuring reliability under real-world conditions.
5. Final Inspection: Each hinge undergoes a 100% final inspection covering dimensions, surface finish, assembly accuracy, and fire-rated components before packaging, ensuring only compliant products are shipped to customers.