The forklift (fig.13-10) is a power-driven piece of
OPERATION
material handling equipment. It is an industrial lift
Forklifts are equipped with a hydraulic cylinder to
truck, either gasoline, diesel, or electrically powered,
raise and lower the fork and one or two cylinders to tilt
and has three or four wheels. It contains vertical
the upright. The tilt cylinders provide the means
uprights and an elevator backplate equipped with a fork
whereby the fork and upright may be tilted forward for
of sufficient length and thickness for use with various
loading and unloading, and tilted aft to stabilize the
types of pallets. Forklifts are generally used to handle
load while transporting it. In addition to these
palletized material like bombs or food, but they may
cylinders, some forklifts are provided with a hydraulic
also be used to haul boxes, containers like jet engine
cylinder, which supplies power to move the carriage
cans equipped with skids, and other large containers
laterally to facilitate manipulation of the fork in con-
and packages.
fined areas.
In addition to the normal controls and indicators
Frequently, loads that could be lifted and
you expect to find on a control panel, you may also find
transported with forklifts are inaccessible to the fork or
an hour meter to measure operating time (for tracking
must be lifted with chains or wire ropes. As a result,
scheduled maintenance) and a load or hydraulic
some forklifts are provided with a detachable boom,
pressure gauge to display the amount of weight being
which may be telescopic. The boom may be attached to
lifted by the forklift.
the upright in place of the fork. A hydraulic cylinder on
the boom supplies the power to extend and retract the
boom to permit accessibility to the load. The chains or
CAUTION
wire ropes required to lift the load are attached to a
If you have a forklift that does not measure the
hook at the end of the boom. The cylinder is connected
load, you should check to see if the weight of the
to the hydraulic system by suitable flexible hose and
load is written on the container. If the container
fittings.
does not list the weight of the load, you can lift the
load very slowly, watching to see if the load raises
the rear wheels of the forklift off the ground. If the
CAUTION
rear wheels lift, the load is too heavy for the
The chain or sling used must be rated to lift the
forklift, and you must get a larger forklift or
required load and be within current load test dates.
reduce the weight of the load.
UPRIGHT
OVERHEAD
GUARD
COUNTER
WEIGHT
CARRIAGE
FORK
STEERING
AXLE
DRIVE AXLE
ASf13010
Figure 13-10.--A typical forklift.
13-16
