2026 Catalog - Flipbook - Page 12
EFFECT OF SLING ANGLE
INCREASED TENSION
1. Determine the load weight (LW).
Plate
Clamps
Lifting
Devices
10
REDUCED CAPACITY
Determine capacity
of sling needed
Vertical
Hitch
a. Determine the sling angle as
measured from the horizontal,
and the corresponding tension
factor (TF) from the e昀昀ect of
angle chart.
OR
b. Length* (L) divided by height*
(H)
3. Determine the share of the load
applied to each sling leg (LW).
4. Multiply (LW) by (TF) to
determine the sling leg tension.
The capacity of the selected
sling or sling leg must meet the
calculated tension value.
Calculate rating of each sling
rigged at this angle
1. Calculate the reduction factor
(RF).
2. Calculate the tension factor (TF):
a. Using the angle from
horizontal, read across
the angle chart to the
corresponding number
in the Reduction Factor
column.
OR
b. Divide sling height* (H)
by sling length* (L).
2. Reduction factor (RF) x the
sling’s rated capacity for the
type hitch that will be used =
sling’s reduced rating.
Choker Hitch
Vertical Basket Hitch
* Measured from a common horizontal plane
to the hoisting hook.
* Measured from a common horizontal plane
to the hoisting hook.
INCREASED TENSION
LW = 500 lbs.
LW = 500 lbs.
Hoist
Rings
Lift-All
Hoists
Cargo
Control
Mesh
Slings
Rigging
Hardware
Chain
Slings
Wire
Rope
Round
Slings
Using slings at an angle can become deadly if that angle is not taken into consideration when selecting
the sling to be used. The tension on each leg of the sling is increased as the angle of lift, from horizontal,
decreases. It is most desirable for a sling to have a larger angle of lift, approaching 90°. Lifts with angles of less
than 30° from horizontal are not recommended. If you can measure the angle of lift or the length and height
of the sling as rigged, you can determine the properly rated sling for your lift. The Increased Tension method
provides the increased tension as a function of the sling angle. Alternatively, the sling Reduced Capacity
method may be used to determine reduced lift capacity for any angle.
Sling
Protection
Web
Slings
General
Information
General Information
Example
Load weight = 1,000 lbs.
Rigging: Two slings in vertical hitch
Lifting weight (LW) per sling = 500 lbs.
Measured sling length (L) = 10 ft.
Measured Sling Height (H) = 5 ft.
Tension factor (TF) = L ÷ H
= 10 ÷ 5 = 2.0
Minimum vertical rated capacity required for
this lift:
= LW X TF
= 500 X 2.0 = 1,000 lbs. per sling
EFFECT OF ANGLE CHART
Tension
Factor
(TF)
Angle
from
Horizontal
Reduction
Factor
(RF)
1.000
90˚
1.000
1.004
85˚
0.996
1.015
80˚
0.985
1.035
75˚
0.966
1.064
70˚
0.940
1.104
65˚
0.906
1.155
60˚
0.866
1.221
55˚
0.819
1.305
50˚
0.766
1.414
45˚
0.707
1.555
40˚
0.643
1.742
35˚
0.574
2.000
30˚
0.500
Sling capacity decreases as the angle
from horizontal decreases.
Sling angles of less than 30° are not
recommended.
REDUCED CAPACITY
Example
Vertical choker rating of ea. sling (VC) = 6,000 lbs.
Measured sling length (L) = 6 ft.
Measured sling height (H) = 4 ft.
Reduction factor (RF) = H ÷ L
= 4 ÷ 6 = 0.667
Reduced sling rating in this con昀椀guration:
= RF X VC
= 0.667 X 6,000 lbs. = 4,000 lbs. of lifting
capacity per sling
