Collapsible Doors
Steel channels 16 to 20 mm wide are utilized as verticals. They are placed with gap 12 to 20 mm. Steel flats 16 mm to 20 mm wide and 5 mm thick are hinged to them
![2020_collapsible doors.png](https://www.expertsmind.com/CMSImages/2020_collapsible%20doors.png)
Elevation
Collapsible steel door
As shown in above figure. The rollers are provided at their top and at bottom so that with slight force shutter can be pushed or pulled sideways. There may be single shutters or double shutters. These doors are used for additional safety usually. Commonly they are used for bank locker rooms, front doors school and college entrance doors.