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 TB 55-1900-232-10
Figure 5-14. Nylon Rope Grommet.
inch IPS fiber core hawser towing on the brake, the following paragraph shows that the comparable nylon grommet would
be made from 15-inch circumference double-braid nylon.
With a spring, the required wire FS is 4, maximum steady working load is 288,000/4 = 72,000 pounds. The required dry
strength of the nylon spring is 72,000 x 14/.85 = 1,185,882 pounds. The nylon rope used in the grommet will require a dry
strength of: 1,185,882 x % = 658,824 pounds. A 15-inch circumference double-braid nylon rope, with a specified dry
breaking strength of 666,000 pounds, will be required for this grommet. The grommet's weight per foot is significantly
more than that of the wire (13.24 vs 6.72 lbs./ft ) and the grommet will be far more bulky!
5-5.2.5 Pendants, Chain and Other Components. Wire pendants require a higher safety factor than the hawser
because of the possibilities of chafing and less care in their handling and storage Chain requires a factor of safety higher
than that of the hawser because chain is often intentionally used at chafing points Other components have the same
factor of safety as the hawser because of the absence of chafing or other hard use in service
5-5.3
PENDANTS AND BRIDLES. A pendant often is used between the tow and towing hawser to facilitate the
rigging problem of connecting heavy components This is called a "lead" or "reaching" pendant. The basic pendant
usually is wire rope and should have the same breaking strength as the main hawser unless it is intended to be the weak
link, in which case it will be of lower strength
Often, the arrangement of the bow of the tow is such that chafing could occur to the tension member that extends
outboard of the bow of the tow. If a wire rope pendant is used in this case, it must be carefully protected from chafing, or
a portion of it must be replaced with chain to provide chafing protection Chain pendants frequently are employed when
using a single-leg attachment between the hawser and tow This attachment generally runs through a
5-27
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