Elevator Types

There are two main types of elevators commonly used: traction and hydraulic; however, there are a number of variations on each type.

Hydraulic Elevators

Hydraulic elevators are supported by a piston at the bottom of the elevator that pushes the elevator up.  They are used for low-rise applications of 2-8 stories and travel at a maximum speed of 200 feet per minute. The machine room for hydraulic elevators is located at the lowest level adjacent to the elevator shaft.

Conventional Hydraulic Elevators have a sheave that extends below the floor of the elevator pit, which accepts the retracting piston as the elevator descends.  Some configurations have a telescoping piston that collapses and requires a shallower hole below the pit.  Max travel distance is approximately 60 feet.

Hole-less Hydraulic Elevators have a piston on either side of the cab.  In this configuration, the telescoping pistons are fixed at the base of the pit and do not require a sheave or hole below the pit.  Telescoping pistons allow up to 50 feet of travel distance.  Non-telescoping pistons only allow about 20 feet of travel distance.

Roped Hydraulic Elevators use a combination of ropes and a piston to move the elevator.  Maximum travel distance is about 60 feet.

Traction Elevators

Traction elevators are lifted by ropes, which pass over a wheel attached to an electric motor above the elevator shaft.  They are used for mid and high-rise applications and have much higher travel speeds than hydraulic elevators.  A counter weight makes the elevators more efficient.

Geared Traction Elevators have a gearbox that is attached to the motor, which drives the wheel that moves the ropes.  Geared traction elevators are capable of travel speeds up to 500 feet per minute.

Gear-less Traction Elevators have the wheel attached directly to the motor.  Gear-less traction elevators are capable of speeds up to 2000 feet per minute.

Machine-Room-Less Elevators are typically traction elevators that do not have a dedicated machine room above the elevator shaft.  The machine sits in the override space and the controls sit above the ceiling adjacent to the elevator shaft.  Machine-room-less elevators are becoming more common; however, many maintenance departments do not like them due to the hassle of working on a ladder as opposed to within a room.

2004 Masterspec Divisions

Elevators: 14 20 00
Electric Traction Elevators: 14 21 00
Hydraulic Elevators: 14 24 00
Elevator Equipment and Controls: 14 28 00