There are two main types of elevators - traction and hydraulic elevators. Traction elevators conventionally use steel cables or belts on a pulley system, while hydraulic lifts and elevators are powered by a hydraulic cylinder, consisting of fluid pistons that move inside a cylinder.
Unlike traction elevators, a hydraulic lift system does not use overhead lifting machines. Instead, these elevators use fluid compression to generate motion. The elevator car is lifted by an electric motor that pumps the oil into the cylinder to move the piston. Hydraulic lifts also incorporate electric valves to control the release of oil for a smooth ride. The fluid needed to power a hydraulic lift must be oil-based.
You can find a hydraulic lift in almost every type of building. However, two factors limit the height they can travel. Hydraulic lifts require a lot of energy to mount the cabin, which is why they are not usually found in tall buildings. These elevators also operate at speeds of 150 fpm, or less, which makes them slower than other types of elevators. Because of these factors, hydraulic lifts are only designed for buildings up to seven stories high.
Hydraulic elevators offer the following advantages, in that they,