The one important use of escalator handrails is mainly to provide a handhold for the escalator passengers. At its most ideal, the handrails should be strong enough and they are to move in synchronization with the movement and speed of the steps.
For one, the handrails cannot move slower or faster than the steps. Any deviation with the speed of either the step or the handrails would result in making its passengers off-balanced.
The synchronization (moving at the same speed) of the steps and the handrails make for a smooth ride.
Composition
Since it is a special part in the whole system, the handrails are made of four (4) sections, each of which has a functional purpose. Together, they make up for a combined function that characterizes the handrails’ importance.
The handrail’s center (known as the glider ply) or a slider in everyday parlance is made of cotton or some man-made cloth. Like its name, the purpose is to make the handrail move smoothly on its tracks as it is pulled by a chain through a series of pulleys from the main drive gear.
Steel cables
The next layer, the tension member, is made of steel cable or some flat steel that gives it flexibility coupled with its built-in strength. This is located on top of the tension member which is a bunch of other construction components found in the inner part of the handrail.
They are all manufactured from chemically-treated rubber that prevents separation of the parts.
Safeguards
At the outermost layer, is the cover that everyone sees. The combination of polymers and rubber makes it resistant to wear and tear and overall degradation. Normally, the body materials for escalator handrails are usually made of glossy chlorosulfonated polyethylene.
These are usually protected against ultraviolet light, high temperature, and ozone concentration. The cover rubber, on the other hand, is made of styrene butadiene. This specially-treated rubber is better than natural rubber.
This type has been proven for its resistance to high temperature which are typical especially on models and units that are in operation 24/7 (all the daytime hours). It also is treated against degradation caused by oil, aging and natural wear abrasion.
Manufacturing process
The handrails are manufactured in the factory with the feeding of the rubber materials through an extrusion machine which produces the many layers in the right sizes and types as specifically ordered. These machines are all computer-controlled to keep away from man-made errors.
After which, the human factor only comes in when these machine-made layers are then shaped and fed into presses by skilled workers. The layers of rubber, steel and fabric are then fused together and form into the handrails that we know and see.
Sometime ago, it is composed of rubber bellows with smooth metal bracelets stringing together each bellow section that were a few feet long. (The idea is simple repair or replacement if a section fails.) Today escalator handrails are now made with fabric, steel and rubber railings that completely fit into one whole rotating mold.
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