|
How to design a
Cantilever Rack System
The
key to a successful
cantilever rack system
is the answer to one
question: What is the
product (load) being
stored? The answer must
include the length,
depth, height and weight
of the product. Once
this data is ascertained
it becomes a simple
matter to determine the
required arms, uprights
and braces.
A.
DETERMINE THE NUMBER AND
SPACING OF ARMS
The load
must be supported by
enough arms to prevent
load deflection.
Deflection may cause
damage to the load being
stored as well as the
arms (figure A1 as shown
below).
To detect
deflection, place the
load over two wooden
blocks (to represent
cantilever arms) as
shown in figure A2.
If
deflection is not
present it is acceptable
to use a two arm system
as long as this does not
create an overload
condition. If the load
shows deflection use
three blocks as shown in
figure A3 or four blocks
as in figure A4.
IMPORTANT: The load
should overhang the end
arms by one-half the
distance from upright
centerline to upright
centerline. Failure to
observe this measure may
cause an overload
condition on the arms.
B.
DETERMINE THE LENGTH OF
THE ARMS
The depth
of the load should never
exceed the length of the
arm. A 48" wide bundle
of plywood requires a
48" long arm, bundles of
steel 24" wide require a
24" arm and so on. Rated
arm capacities may be
seriously diminished if
proper loading
techniques are not
observed. Figures B1, B2
and B3 illustrate
correct and incorrect
arm loading.
NOTE: All
arm capacities are based
on an evenly distributed
load as in figures B4
and B5 below.
C.
DETERMINE THE HEIGHT OF
THE UPRIGHT
When
determining the height
of the upright it is
important to consider
the ceiling height,
forklift reach,
sprinkler systems and
other factors, such as
local building codes
that might affect the
overall height. The
height of the upright in
figure C1 is determined
by adding the base
height, the number of
loads to be stored, the
arm thickness plus 6"
clearance between the
load and next arm.
IMPORTANT: The load
placed on the base does
not diminish the rated
capacity of the upright.
Thus, the heaviest loads
should be placed on the
base.
D.
DETERMINE ARM AND
UPRIGHT CAPACITIES
As
previously discussed,
each arm supports an
equal amount of the
load’s weight. By
determining the number
of arms per level and
dividing it into the
weight per level, the
required arm capacity
can be determined (see
example at above). To
determine the required
capacity of each
upright, multiply the
number of arms per side
by the load on each arm.
In figure D1, each arm
holds 2500 lbs. Twelve
arms per side times 2500
lbs. per arm equals
30,000 lbs., which when
divided by three
uprights, results in a
required minimum
capacity of 10,000 lbs.
per upright. The correct
upright can be selected
by matching the minimum
upright capacity of
10,000 lbs. with the
upright capacities set
forth on the following
pages. Assuming a 48"
arm, the U1061-NS on
page 22 with 10,200 lbs.
capacity and the U1061
on page 23 with 12,600
lbs. capacity are the
only uprights that will
handle the load. NOTE:
The Series 1000 MU1057
has only 3100 lbs.
capacity while the
Series 2000 2U1062 has
8600 lbs. capacity.
E.
DETERMINE BRACE LENGTH
Brace
length is defined as the
horizontal distance from
centerline of upright to
centerline of the next
upright. Refer to the
various brace set charts
for the brace length
that most closely
matches the arm spacing
determined in step A.
Now that
you know how to design a
Cantilever Rack System,
all you have to do, is
to add the
specifications into our
on-line quote system and
we will provide you with
a free quote.
Click
here to request your
Free Quote for your
custom Cantilever
Shelving project.
|
