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SLINGS
WIRE ROPE
GENERAL INFORMATION
TABLE 6
NOMINAL SPLICE EFFICIENCIES
STRAND LAID TUCKED GROMMETS
Nominal Eff.
Rope Dia.
Nominal Eff. Factor
Rope Dia.
Factor
1/4
0.78
1 3/8
0.745
5/16
0.78
1 1/2
0.735
3/8
0.78
1 5/8
0.73
7/16
0.78
1 3/4
0.725
1/2
0.78
1 7/8
0.72
9/16
0.78
2
0.715
5/8
0.78
2 1/8
0.71
3/4
0.78
2 1/4
0.705
7/8
0.78
2 3/8
0.7
1
0.775
2 1/2
0.695
1 1/8
0.765
2 3/4
0.69
1 1/4
0.755
3
0.685
ferential measurement. The requirement for a minimum
type hitch therefore the presence of the nominal splice effi
circumference of 96 times the body diameter for grommets
ciency factor in the equation. Rated capacity adjustment
and endless slings was based on the requirement to have
table 1 applies.
at least three free rope lays on either side of the tuck of a
hand spliced endless grommet prior to being bent around
STRAND LAID MECHANICAL SPLICE GROMMET
a hook or pin five times the body diameter. To eliminate
the possibility of confusion, this requirement was adopted
Strand Laid Mechanical Splice grommets are made from
for mechanically spliced endless grommets as well. con
one continuous length of wire rope joined by pressing or
sult the sling manufacturer for smaller circumferences.
swaging one or more sleeves over the rope juncture. This
type of grommet is not as smooth as the hand tucked, but
The same general precautions apply to grommets as apply
offers economy and ease of manufacture. An advantage
to all other types of slings. However, it should be noted
is that the swaged sleeves give clear indication of the
that since a grommet is a continuous circle, the noted D/d
splice area.
ratio becomes a very important consideration. The D/d
ratio must be applied to the lifting pins as well as the load.
CABLE LAID HAND TUCKED GROMMET
normally the lifting pins will be the smallest diameter in the
Cable Laid Hand Tucked Grommets are fabricated in the
system other than the diameter of the grommet. No loads
same manner as strand laid hand tucked grommets except
should be handled on the D/d smaller than the 5 times the
one continuous length of wire rope is used. This makes
sling body diameter. If they must, consult the sling manu
for a flexible smooth sling. the body diameters are some
facturer. Rated capacities covered in the section are
what odd sized because the grommet body is built up from
based on a D/d ratio of 5.
a standard diameter component rope.
STRAND LAID HAND TUCKED GROMMET
CABLE LAID MECHANICAL SPLICE
A Strand Laid Hand Tucked Grommet is made from one
(See Rated Capacity Tables Section)
continuous length of strand. No sleeves are used to make
Cable Laid Mechanical Splice Grommets are fabricated
the joint. This results in a very smooth circular sling.
from one continuous length of cable laid wire rope fabric
with the ends joined by one or more mechanical sleeves.
Because of the sling body construction, grommet slings
react differently than standard wire rope slings in a choker
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