General Design Guidance
2-2.1 Consult with the NAVFAC Elevator Program Manager, EFD Elevator Program Manager,
or PWC Elevator Inspector during the preliminary design of facilities that include
elevators. The Navy elevator experts can be located by using phone numbers and e-mail
addresses from Chapter 6 "Specifications Elevator Design Guide."
2-2.2 Type of elevators addressed:
(1) Direct plunger: A car is connected to the top of a single section piston, that moves
up and down in a cylinder, which is below ground level. The car moves up when
hydraulic fluid is pumped into the cylinder from a reservoir, raising the piston.
Hydraulic systems are used primarily in low-rise installations where moderate car
speed is required, up to 150 feet per minute. The typical extent of travel is 40 feet
(12192 mm), do not exceed a maximum travel length of 44 feet (13411 mm) or a
maximum building height of four floors for Navy facilities.
(2) Holeless: The car is connected on each side with a single section piston that
moves up and down in a cylinder, which is mounted on top of the pit floor. The car
moves up when hydraulic fluid is pumped into the cylinder from a reservoir, raising
the piston. Car speed up to 125 feet per minute (38.1 meters per minute) is attained
and maximum travel length is 12 feet (3658 mm).
(3) Roped: The car is supported by steel hoist ropes and sheave, which are moved up
and down by a holeless single section piston in a cylinder. Car speed up to 150 feet
per minute is attained and maximum travel length is 48 feet (14630 mm). The use of
roped hydraulic elevators for Navy facilities must be approved by the NAVFAC
Elevator Program Manager.
b. Electric Traction
(1) Geared: The car is supported in a hoistway by steel hoist ropes, a
sheave, and a counterweight. The car and counterweight ride along vertical
guide rails. In a geared machine, the drive sheave is connected to the motor
applications of five or more floors requiring typical speeds up to 350 feet per
(2) Gearless: The car is supported in a hoistway by steel hoist ropes, sheaves,
and a counterweight. The car, counterweight and guide rails operate like those
in a geared system. The gearless machine has a motor that connects directly to
the shaft of the drive sheave. The equipment is designed for high-rise
applications of 10 or more floors requiring typical speeds of 500 or more feet