The ASSA ABLOY DC340-D35 is an exemplary hydraulic door closer, engineered for precision control and longevity. Its core functionality is rooted in a highly refined hydraulic system, featuring independent adjustable valves for critical operational parameters.
1. **Hydraulic Mechanics and Precision Control**: The DC340-D35 employs a sophisticated hydraulic mechanism that precisely modulates door movement throughout its operational arc. Independent adjustable valves for 'closing speed control' and 'latching speed control' allow installers to fine-tune the door's momentum from its maximum opening angle (up to 180°) down to the final few degrees before closure. This prevents uncontrolled slamming, protects door hardware, and enhances user safety.
* The 'back-check' feature, an essential hydraulic damping mechanism, engages automatically when the door is opened beyond a predetermined angle. This provides resistance against aggressive opening, preventing damage to the door, frame, and adjacent walls, especially in windy conditions or areas with high pedestrian traffic.
* 'Delayed action' functionality further enhances user convenience, holding the door open at a slower, controlled rate for an extended period before the closing cycle begins. This is particularly beneficial for wheelchair users, individuals carrying objects, or in high-traffic commercial settings requiring brief, sustained open times.
2. **EN1154 Compliance and Performance**: Certification to EN1154 is a fundamental pillar of the DC340-D35's engineering credibility. This European standard specifies requirements for controlled door closing devices, covering aspects such as closing power, durability, efficiency, and safety. The adjustable power size range of EN2-6 (typical) signifies that the closer can be precisely configured to meet varying door sizes and weights (up to 1400 mm width with a link arm) and wind load requirements, ensuring consistent closing force across a broad application spectrum. The EN1154 certification validates its reliability and consistent performance under specified test conditions.
3. **Durability and Build Quality**: Constructed from stainless steel for both its body and articulated arm, the DC340-D35 exhibits exceptional resistance to corrosion and wear, suitable for demanding environments. The specified '2,000,000 cycles (approx.)' test rating underscores the robust design and material integrity, far exceeding typical operational expectations and ensuring a significantly extended service life. The unit's non-handed design simplifies specification and installation, reducing inventory complexity. While engineered for superior mechanical performance and control, it is critical to note that the DC340-D35 is *not* fire-rated. Therefore, it is unsuitable for applications where fire compartmentation compliance requires fire-rated door closers.
