Traction Elevators

It can sometimes be difficult to tell which type of elevator you are riding unless you are able to see the mechanisms that are powering it. For example, traction elevators use a series of ropes, cables, sheaves, and counterweight to move up and down. Hydraulic elevators, on the other hand, are powered by electronic pumps that transmit the hydraulic fluid to the jack. Then, a piston at the base pushes it up. Different types of elevators exist because not all buildings are alike. Some are better suited for fast, high-rise transportation while others are designed for smaller, residential buildings. Whatever elevator type you are looking to construct, it is important to have all of the information available before making a decision. As the most common elevator system used in commercial buildings today, here’s our explanation of traction elevators and their advantages and disadvantages. 

Traction Elevators 101

On a traction elevator, the cab is raised and lowered by a series of traction steel ropes or belts on a pulley system. They use a counterweight to offset the weight of the cab and its occupants. This design allows less pressure on the motor and does not require it to move as much weight. 

Traction elevators have two different model types; geared and gearless. Both are driven by alternating current (AC) or direct current (DC) electrical motors. In geared elevators, a gearbox is attached to the motor and is responsible for driving the wheel and moving the ropes. These models can get up to speeds of 500 ft per minute and typically run middle-of-the-road in terms of cost. Gearless traction elevators, on the other hand, have the sheave directly attached to the end of the motor. These models can reach speeds up to 2,000 ft per minute and typically have a higher initial investment cost. However, gearless traction elevators are more energy-efficient than geared traction elevators.

Advantages of Installing a Traction Elevator: 

• Higher speeds allow it to be used in taller and more modern 21st century buildings.
• Uses a counterweight to offset the weight of the cab and occupants. With this design, the motor doesn’t have to move as much weight, making it much more energy-efficient than hydraulic systems.
• Ability to install a magnetic synchronous motor, which would replace the main machine room, provide a superior control mechanism, and make the entire system safer and easier to maintain.

Disadvantages of Installing a Traction Elevator:

• Higher installation costs as there are more components to be installed compared to a hydraulic system.
• Difficult to maintain as the main controls for the elevator are located in the difficult to access shaft headroom. 
• Crane is typically required as the building’s roof cannot be installed over the elevator’s hoistway.

Whether you are updating an existing system or figuring out which type of elevator should go into a new building, it is important to get all the information before making a final decision. While traction elevators are the most common, they are not the only type of elevator. Looking for something less expensive and capable of carrying more weight, then check out our other article about hydraulic elevators. If you would like to learn more about your options and get expert recommendations, contact the experts at Cardinal Elevator today.