Hydraulic elevators are a well known system used in hundreds of lifts across the world (alongside Traction Lift systems), as well as a huge amount of machinery and equipment using the same principles.
Make sure your lift is kept in top condition by understanding how it works and recognising any differences before a problem occurs – or to decide which type of lift is the right one for your business or public building.
Hydraulic lifts work on a basic principle: to go up, a pump pushes oil into the cylinder, pushing the piston (which pushes the lift car) up. To go down, the valve opens and oil is allowed to flow back into the reservoir, and is pushed back using the gravitational force of the lift car. The diagram above shows this system.
When the valve is closed, the oil can only go from the reservoir into the cylinder. When the valve is open, the oil can only flow from the cylinder back into the reservoir.
The controls in the lift car make the pump operate, moving the oil. When a floor is reached, the pump is switched off and the lift car sits on top of the piston, held in position by the oil which is trapped in the cylinder.