What's the difference between a sequential device and a door closer?

The difference between the sequential device and the door closer is 1, with different functions: the sequential device is used for double doors with tenons and grooves to control the closing sequence of the doors, and the door closer has the function of automatically closing the doors. 2. Different installation methods: the exposed door closers are mainly located in the main body, such as door leaves or doors or door frames, while the concealed ones are hidden in the door leaves, and no metal parts can be seen from the outside. 3. The presentation effect is different: the door closer can't be seen on the surface of the hidden door closer, but only the slideway can be seen when it is opened. All components of the surface-mounted door closer are external.

Sequential device is a product used on fire doors according to the standard requirements of General Technical Conditions for Steel Fire Doors (GB 12955). Its main function is to prevent two doors from being clamped together when they are closed in case of fire. After installing the sequence device, the doors can be closed in series when closing.

Door closer is a spring-like hydraulic device on the door head. When the door is opened, it can be released after compression and the door will close automatically. It has the function of spring door, which can ensure the door to close to the initial position accurately and timely after opening.

Modern hydraulic door closers (door closers for short) began with a patent registered by Americans in the early 20th century. Different from the traditional door closer, it achieves the buffering effect by throttling the liquid in the door closer. The core of the design idea of hydraulic door closer is to control the door closing process, so that the functional indexes of the door closing process can be adjusted according to people's needs.