A sliding is a door which open horizontally or parallel to a wall. There are many types of these doors. Some of them build up on a track on the bottom or the other type hang on the above. There are other types which can be disappeared in the wall. They have different names to call with such as pocket doors, bypass doors and Arcadia doors. The very common use of these doors is in shower, as glass doors, as wardrobe doors, as well as screen doors. The use of sliding door is started back in first century CE, people of Rome used these doors in their houses and its oldest example is in Pompeii, Italy which was found by archaeologists.
Sliding door gear is the mechanism used to operate these doors, there are two very basic types of these gears first is top hung and the other is bottom rolling gears. There is no perfect and strong seal in both types. The common use is of brush seals to lessen the air-and-smoke tightness, and sound insulation.
The most regular system that has been used is top hung system, in this system the door hung from the two trolley hangers and these hangers are fixed in a hidden track. Hungers do control all the weight which makes it easy for door to move smoothly.
There is a track stopper on the each end to take up the impact if the door bangs and the stoppers also hold the doors in the open and close position. The top hanging type doors gear systems have a limited maximum weight per pair of the trolley hangers. The weight of the door is the very essential factor to consider and also a hard one when one decides to install this type of door, many manufacturers can suggest you better about the weight of the door. This door also needs a bottom door even if it will hang on the above. This bottom track is also known as stay roller. It prevents the door from wavering sideways. A floor-fix plastic guide which is of 60mm wide is the most common type and it is known as clear threshold guiding. It gets fixed on the bottom of the door. A groove runs over the guide and prevents side movements of the door.
Bottom rolling door gears are the alternatives for top hand doors. They can be used at a place where it gets impossible to install top hanging ones because the wall or roof unable to support the weight.
This system has two rollers at the bottom operating in the tracks and two guides at the top operating in guide channels. There are two bottom wheels to handle the weight of the door. This type of door requires more force than top bottom to move.
Lift sliding doors need to be lifted from the frame to open and closing them. They prove better seal and sound proofed.
Automatic sliding doors contain a motor and an activation system to be opened. These types of doors are common for office use and shop entrances. They have magnetic locks for emergencies.