Elevators have been in existence for over 2000 years and have undergone quite the technological transformation. For this reason alone, modern skyscrapers reaching hundreds of feet would not be possible, as getting to the top would be highly inconvenient, not to mention feasible. Early versions of the elevator consisted of a rope and pulley system using a counterweight, typically man or equine-powered, rudimentary but it worked to move goods and people vertically. Elevators provide a means to convey people or goods between floors within a building or other structure. They are essential in practically any multi-floor structure to provide universal access for all patrons including handicapped individuals.
Early versions of the elevator posed a major risk due to lack of safety mechanisms to prevent them from free-falling. A safety device developed by Elisha Otis in the mid-1800’s, still in use today, revolutionized the elevator, allowing it to evolve into what it is today. Elevators are classified according to the mechanism used to hoist or lift them, such as traction, climbing, pneumatic, and hydraulic, and within each classification, there are various sub-groups. Hydraulic Elevators in Washington DC are also called “push” elevators because the piston that supports the elevator pushes the unit up the shaft while the motor forces hydraulic fluid into the piston.
The opposite occurs (fluid is released from the piston) in order for the elevator to descend. Hydraulic elevators are primarily used in buildings less than 10 stories due to their slower speeds. Hydraulic elevators travel at maximum speeds of about 200 feet per minute which is slightly more than 2 miles per hour. As a point of reference, the third fastest elevator in the world located in the John Hancock Tower in Chicago, travels 1,801 feet per minute or 20.5 mph. Two types of hydraulic elevators are holed (conventional) and hole-less.
As expected, due to their repeated usage, having routine maintenance performed by professionals like those at, will keep an elevator in top-running condition. At a minimum, twice-annual maintenance performed by a licensed technician includes cleaning and lubricating the moving components. It is critical that the hydraulic fluid in the piston is checked for proper levels and especially for leaks. Electrical components such as wiring and circuits, operating controls, and control units are inspected and findings logged.
