How to Prevent Common Elevator Problems Through Routine Maintenance

Machinist worker adjusting elevator mechanism of lift.

In all types of elevators — whether freight or passenger — electric motors and braking systems are used to allow the cars to move up and down. These components work in tandem with a system of cables and pulleys positioned between the cars and the motors, while counterweights help balance the cars. There are also many safety systems in place to protect passengers, materials being transported, and other components in the event of cable breakage. For instance, electronic control systems in large residential or commercial buildings use a mathematical “elevator algorithm” to most efficiently calculate the ratio of people wanting to go up or down depending on the time of the day, and the best way to serve those needs.

Elevator Component Upkeep

Elevators are comprised of many different components, so routine maintenance of these parts is critical for ensuring safe and reliable elevator performance. Components in the hoistway, the elevator car, and the machine room are equally important, as the counterweight and elevator car run on guide rails in the hoistway. The counterweight, which weighs about the same as the elevator car when it’s half-full, decreases the amount of energy required by the motor.

The less stress placed on the cables, the safer the elevator is. And less stress on the cables also means reduced stress on the brakes. Most elevators also have a speed-regulating system called a governor. If an elevator gains too much speed, the massive mechanical arms of a flywheel operating system will slow it down by applying the brakes or cutting power to the motor. The elevator motors, switches, generators, brakes, and controls are typically located in the machine room, where the majority of maintenance takes place.

AC and DC drives are also frequently used to regulate speed and positioning and should be regularly checked for optimal functioning. Each drive has various control options for horsepower and speed, but the specific application and environment play a crucial role in the exact type of drive used. Other routine maintenance protocols will be stated in the elevator’s operating and maintenance contract.

Preventative Elevator Maintenance

Checking bearings, ensuring proper lubrication and sealing, and evaluating brake shoes and pulleys will all help ensure optimal elevator performance and safety. Loose tires, bad bearings, and door rollers with flat spots must all be replaced as soon as the issue is identified. All bearings should allow for quiet operation and fit tightly, and no loose screws or keys should be present. All worn belt parts should be replaced or adjusted as needed, and any bearings or gears that are running at high temperatures should be checked out. Sheave bearings must be quiet, and sheave grooves must not contain any foreign matter.

Lubricants should never be gummy or thickened, and operators should adhere to a manufacturer-recommended lubrication schedule. Brake cores and pivots, rails used with slide guides, hoist ropes, nonmetallic sheave liners, external gears, and machine roller and ball bearings must all be lubricated in accordance with manufacturer specifications.

It is the responsibility of the owner to ensure that test seals and tags are in place, although some leakage of worm shaft seals is acceptable. Additionally, brake shoes should have minimal lift without dragging, and pulley surfaces should be smooth with no excessive scoring. Carbon brushes should be free in the holders and of sufficient length.

With proper preventive maintenance, many common elevator problems can be easily avoided, thereby reducing extra expenditures, labor needs, and downtime.

 

Image credit: Dmitry Kalinovsky /Shutterstock.com

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