The UL Fireproof Silent Concealed Cam Action Door Closer is positioned as a high-performance concealed door control solution for fire-rated and commercial applications that require smooth operation and architectural aesthetics. Manufactured from durable aluminium alloy, it combines lightweight strength with long-term reliability. Featuring advanced cam action technology, it delivers efficient closing force with reduced opening resistance and exceptionally smooth, quiet operation, enhancing user comfort in high-traffic environments. UL Listed for 3-hour fire-rated doors (File No.: R40717), it is designed to maintain door integrity and controlled closing during fire conditions, supporting life safety compliance. Installed discreetly within the door leaf or frame, this hidden door closer is ideal for fire-rated wooden and metal doors in offices, hospitals, hotels, schools, and other public or commercial buildings where safety certification, noise control, and clean design are essential.
Technical Specifications
| Max. Door Width |
1100 mm |
| Door Weight Capacity |
20–80 kg |
| Power Size |
Adjustable Size 2–4 |
| Max. Opening Angle |
Dual Swing 120° |
| Construction |
Ductile Iron Shell, Aluminium Alloy Components |
| Certifications |
UL Listed (3 Hours Fire-Rated, File No.: R40717); Complies with EN1154 Standard |
| Optional Feature |
Hold Open Function |
Product Images and Videos
Product Features & Advantages
- Cam Action Mechanism: The cam action mechanism ensures exceptionally smooth and silent door closing and opening. Compared to traditional rack-and-pinion systems, cam action technology significantly reduces operational noise and resistance, making it ideal for quiet commercial environments such as hotels, offices, hospitals, and meeting rooms where acoustic comfort is essential.
- UL Listed (3 Hours Fire-Rated): Certified under UL File No.: R40717, the DDDC052 door closer meets stringent 3-hour fire-rating requirements. This certification confirms its ability to maintain performance during fire conditions, helping prevent the spread of smoke and flames while supporting life-safety compliance in commercial and institutional buildings.
- Concealed Design: The concealed installation design allows the closer to be hidden within the door leaf or frame, preserving a clean and minimalist architectural appearance. This unobtrusive structure integrates seamlessly with modern interiors and concealed hinges, making it especially suitable for high-end commercial and hospitality projects.
- Adjustable Spring Force (Size 2–4): The adjustable spring force range (Size 2–4) enables precise tuning according to door weight between 20–80 kg and door width up to 1100 mm. This flexibility ensures optimal closing control for various applications, including retail stores, conference rooms, administrative offices, and commercial corridors.
- Durable Construction: Constructed with a robust ductile iron shell combined with aluminium alloy components, the door closer offers excellent mechanical strength, wear resistance, and long-term durability. The materials are engineered to withstand heavy daily usage in high-traffic commercial environments.
- Optional Hold Open Function: An optional hold-open feature allows doors to remain open at a predetermined angle when required. This function is particularly useful in spaces such as mall entrances, school corridors, and commercial lobbies where temporary open-door access improves convenience and traffic flow.
Application Scenarios
The DDDC052 Fireproof Silent Hidden Door Closer is designed for environments that demand fire safety, quiet functionality, and refined aesthetics.
In hotel luxury suites, its concealed design preserves premium interior aesthetics while integrating seamlessly with door locks to ensure guest privacy and comfort. In office building boardrooms, the UL 3-hour fire rating supports corporate safety standards, while the silent cam action maintains a distraction-free meeting environment.
Within hospital patient wings, smooth and noise-free operation enhances patient comfort and reduces disturbance. In high-end retail stores and shopping malls, the closer ensures controlled door movement while maintaining a sleek architectural appearance. School administrative offices and modern commercial lobbies also benefit from its adjustable spring force and optional hold-open functionality, supporting both safety and accessibility needs.
Value for Buyers
- Sleek Concealed Aesthetics: The hidden installation maintains a clean and modern design language, making it ideal for projects with strict architectural and interior design standards.
- Fire Safety Compliance: UL 3-hour fire certification minimizes liability risks and ensures adherence to building codes and life-safety regulations in commercial environments.
- Silent Cam Action Operation: Low-noise performance enhances user experience in sensitive environments such as hospitals, hotels, executive offices, and conference rooms.
- Systematic Procurement: Full compatibility with D&D’s comprehensive door hardware portfolio enables buyers to consolidate sourcing, simplify logistics, and maintain consistent product standards across projects.
- Adjustable Performance: Spring force adjustability (Size 2–4) and optional hold-open configuration provide operational flexibility across diverse door sizes and usage requirements.
Certifications and Compliance
The DDDC052 Door Closer meets rigorous international standards for safety, performance, and quality:
- UL Listed (3 Hours Fire-Rated): Certified under File No.: R40717, validating reliable fire protection performance during emergency situations.
- EN1154 Compliance: Meets European standards governing door closer durability, closing force accuracy, and operational safety.
- ISO 9001 Quality System: Manufactured within D&D’s ISO 9001-certified quality management system, ensuring strict quality control from raw material sourcing through final inspection.
Customization Options
D&D offers customization for the DDDC052 door closer to meet project-specific needs:
- Hold Open Function Integration: Optional hold-open mechanisms can be integrated or modified according to accessibility requirements and project-specific traffic flow needs.
- Surface Finish Customization: Custom finishes for the ductile iron shell or aluminium components—such as brushed metal textures or powder coatings—can be provided to align with architectural themes and door hardware styles.
- Spring Force Tuning: Beyond the standard Size 2–4 range, customized spring force adjustments can be developed for specialized door weights or performance requirements.
Production Process & Quality Control
- Material Sourcing: High-grade ductile iron and aluminium alloy are selected and tested to ensure structural strength, durability, and fire-rated compliance.
- Precision Manufacturing: Advanced CNC machining technology is used to produce the shell, internal components, and cam mechanism with high dimensional accuracy, ensuring smooth and consistent performance.
- Assembly & Calibration: Cam systems, spring mechanisms, and optional hold-open components are carefully assembled and calibrated to meet Size 2–4 performance requirements and ensure precise closing control.
- Quality Inspection: Each door closer undergoes comprehensive functional testing, including cam action verification, closing speed control, and simulated fire performance evaluation, along with detailed visual inspection.
- Certification Testing: Random samples are tested in accordance with UL and EN1154 standards to confirm fire resistance, durability, and mechanical accuracy.
- Packaging: Products are securely packaged in protective white, color, or customized cartons with clear labeling to prevent damage during transportation and facilitate efficient project logistics.
Installation Steps
- Prepare Door & Frame: Verify that the door width (≤1100 mm) and weight (20–80 kg) comply with DDDC052 specifications. Prepare essential tools such as a drill, screwdriver, and measuring tape to ensure accurate positioning and alignment before installation.
- Install Concealed Closer Unit: Mount the ductile iron shell and aluminium components inside the door leaf or frame according to concealed installation guidelines. Ensure secure fixation and precise positioning to maintain smooth cam action performance.
- Adjust Cam Action & Spring Force: Calibrate the cam mechanism to achieve silent and controlled movement. Adjust the spring force within Size 2–4 to match the specific door weight and operational requirements for balanced closing speed and latching performance.
- Configure Hold Open (Optional): If the hold-open function is required, set the desired holding angle during installation. Confirm that the door remains stable at the selected angle without affecting fire safety compliance where applicable.
- Verify Operation & Integration: Test the full opening and closing cycle multiple times to confirm smooth, quiet operation. Ensure compatibility with door locks, concealed hinges, and door stops to guarantee coordinated system performance.
