NHN A-40 Center Hang Type Auto Hinge

NHN Auto Hinge™ Center Hang – A-40

The NHN Auto Hinge™ A-40 is a concealed center-hang self-closing door hinge for heavy swing doors. It combines hydraulic control and spring technology in a built-in pivot mechanism and is listed as an A series model with no corresponding AFD-M model.

Technical Specifications

• Model: A-40
• Series: A series
• Maximum door width: 4000 mm
• Maximum door height: 3000 mm
• Minimum door thickness: 65 mm
• Maximum door weight: 1000 kg
• Maximum opening angle: 180° right- or left-hand one-side opening
• Standard closing force: 78.5 N·m
• Applicable door weight: up to 83 kg/m²
• Applicable door type: Steel door
• Top pivot: Screw-type top pivot (N-25B)
• Spring set system: Roll-in system
• Closing force adjustment: adjustable by winding the spring
• Closing speed adjustment: adjustable through the speed-control gear
• Door opening direction: right or left, one-side opening
• Model-specific difference: screw-type top pivot; no corresponding AFD-M model is listed.

Construction and operation

The center-hang design is built into the door construction, keeping the automatic closing mechanism concealed and maintaining a clean door appearance. The hydraulic control mechanism works with the spring mechanism to provide controlled closing. The closing force can be adjusted by winding the spring, while the closing speed can be adjusted through the speed-control gear.

One complete set consists of the main hinge, receptive base, top pivot and decorative rubber plates. The standard installation uses the roll-in spring set system. A fixed-type floor receptive base is available as an option where the sliding receptive base is not suitable.

Model-specific information

A-40 is listed as an A series model. The KENWA Japan catalog identifies the corresponding A-series model as A-40A, while the current KENWA America listing uses A-40. No AFD counterpart is listed for this model.

SEO article

NHN A-40 is a heavy-duty concealed center-hang automatic hinge designed for large swing doors. It supports doors up to 4000 mm wide, 3000 mm high and 1000 kg, with 180° right- or left-hand one-side opening. The A-series configuration uses a screw-type top pivot and adjustable hydraulic and spring closing control.