LUBRICATION of escalators and MOVING walkways

Importance of lubrication of escalators and moving walkways

The mechanical parts of escalators and moving walkways need lubrication. Lubrication promotes the movement of mating components and reduces wear, heat, friction, abrasion and noise. Without lubrication, components require more frequent maintenance, increase the risk of fire and shorten service life.

Lubricants can be in various forms such as solid, liquid, grease or gaseous. The lubricants used for escalators and moving walkways are oil and grease. The viscosity of lubricants is one of the important factors affecting lubrication. Viscosity refers to the internal friction of a fluid that causes it to resist flow.

Where and how to lubricate escalators and moving walkways?

Escalators and moving walkways need lubrication of the following parts:

Main drive shaft bearing
Handrail drive shaft bearing
Tensioner bearing
Drive chain
Handrail drive chain
Step chain
Worm gearbox
Motor brake pin
There are two common methods of lubricating escalator parts:
Manual lubrication
Automatic lubrication

Manual lubrication is performed by technicians during maintenance. In this type of lubrication, the technician applies the lubricant to the escalator parts using appropriate tools. Manual lubrication is applied to the gearbox and brake pin of the motor, as well as to grease lubricated parts. The amount and duration of manual lubrication should be in accordance with the factory manual.

Most lubrication systems used in industry today are automatic and are programmed to lubricate components at periodic intervals without human intervention. Automatic lubrication, as the term implies, is the automatic lubrication of escalator components by creating lubrication systems consisting of oil pumps that pump oil through lubrication pipes to brushes located on the parts of the device to be lubricated and then lubricate those parts. The drive chain, handrail drive chain and step chain are the main parts of escalators and moving walkways that need automatic lubrication.

In addition, the lubrication pump must operate at various temperatures from -20 °C to +60 °C and the lubrication tank capacity must be proportional. Automatic lubrication pumps are equipped with a button for manual lubrication. During maintenance, in addition to checking the oil level in the tank, technicians should also check the oil pump drive switch to ensure that it is working properly.

Over- or under-lubrication of escalators and moving walkways

One common problem with lubricating escalators and moving walkways is applying the right amount of lubricant to the components. Excessive amounts of lubricant will contaminate the escalator and make the surfaces of the steps dirty and slippery. Passengers can slip, fall and get injured. Insufficient lubrication of the escalator and moving step leads to friction and wear of components and, as a result, noisy operation.

In order to collect oil flowing into the interior of the escalator, several trays should be provided to collect excess oil in the direction of travel. In addition, a fully open escalator may be equipped with a water-oil separation device in the lower machine room that separates excess oil and water, allowing maintenance personnel to easily clean the machine room of oil.