1, the use of door closer requirements and choices
Door closer products must meet the national standard GB9305-88, and the door closers used for fire doors should also meet the requirements of GA93-1995 "Closer Test for Fire Doors".
The factors that should be considered when choosing a door closer are: the weight of the door, the width of the door, the frequency of opening the door, and the requirements for use and use. The weight of the door and the width of the door are the most important factors in selecting the type of door closer. Common doors include fire doors, wooden doors, aluminum doors, glass doors, steel doors, and the like. Usually the weight of the door is small, and the model with less power is selected, and vice versa. The opening frequency is a factor closely related to the quality of the product. For frequent use, the sealing performance of the product should be good and the service life should be long.
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