Door closer products must meet the national standard GB2698-2005, and fire door closers should also meet the requirements of GA93-1995 "Test of Door Closers for Fire Doors". Factors to consider when selecting a door closer include: door width, opening frequency, usage requirements, and usage environment. Door width is the most important factor in selecting a door closer model. Common types of doors include fire doors, wooden doors, aluminum alloy doors, glass doors, and steel doors. Generally, if the door is lightweight, a model with less force should be selected, and vice versa. The opening frequency is a factor closely related to product quality. For frequently used applications, the product should have good sealing performance and a long service life.
Is an automatic door-stopping function required after opening?
1) Damping buffer function – After the door is quickly opened to a certain position, a damping buffer is generated, and the damping force and range can be adjusted according to usage requirements. This function is used to prevent the door or lock from hitting the wall when opening the door quickly with force, or to prevent people from losing their balance and falling forward when opening the door quickly during an emergency escape.
2) Delayed slow closing – The door closes slowly and evenly from its maximum open position, and can be steplessly adjusted as needed. Suitable for places with frequent traffic and many people, especially hospitals, and doors and passageways for the elderly, children, and disabled.
3) Adjustable closing force – Can be installed on doors with a wide range of weights and widths, and in places where the closing resistance is high due to environmental factors. Stepless adjustment can obtain satisfactory closing force, especially in coastal cities, vehicles, ships, and other places where the closing resistance (force on the door) frequently changes due to wind.
4) Damping Reset Function Temporary Closing Performance (Vertical Door Closer) – When opened to any angle, closing the speed control valve should temporarily pause the damping reset function.
5) Safe and Rapid Over-Damping Closing Performance (Vertical Door Closer) – When a sudden external force is applied during closing to any angle, it should be able to close safely and rapidly.
6) Operating Environment: Fire protection requirements and anti-freezing requirements in locations with temperatures as low as -35°C in winter.
Generally, door closers can be selected based on the manufacturer's product specifications, with different force values or adjustable force values to match different door sizes and weights. The table below shows the test door weight/size for seven levels specified in British Standard BS EN 1154 (a recognized standard for classifying door closers). The closing force of a door closer is usually specified as a value between 1 and 7; the higher the number, the greater the capacity of the door closer.
