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Figure 4-2.–Detachable link.
for back fit. All links are studded; that is, a piece of steel
is placed in the center of the links. Studs prevent the
chain from kinking and the links from pounding on
adjacent links. The Naval Ships' Technical Manual lists
standard sizes from 3/4 inch to 4 3/4 inches, and details
the method of fabrication. The size of the link is
designated by its nominal diameter, which is called wire
diameter. Wire diameter is measured at the end of the
link a little above the center line. The length of a
standard link is 6 times its wire diameter, and its width
is 3.6 times its wire diameter.
An anchor chain is made up of many parts besides
common links and requires a variety of equipment and
fittings to use and maintain the chain. The following
descriptions will acquaint you with the details of anchor
chain and some of the equipment associated with using
and maintaining the chain.
Standard Shot
The lengths of chain that are connected to make up
the ship's anchor chain are called shots and are made up
with an odd number of links. A standard shot is 15
fathoms (90 feet) long. At the time of its manufacture,
each shot of the chain usually bears a serial number
stamped, cut, or cast on the inner side of the end links
of each shot. If an end link is lost or removed from a
shot, this identification should be cut or stamped on the
inside of the new end link of the altered shot.
Chapter 581, Naval Ships' Technical Manual, defines in
considerable detail chain make-up, fittings, replace-
ment, maintenance and rejection criteria.
Detachable Links
Shots of anchor chain are joined by a detachable
link, shown in figure 4-2. The Navy-type detachable
link consists of a C-shaped link with two coupling
plates that form one side and stud of the link A taper pin
holds the parts together and is locked in place at the
large end by a lead plug. Detachable link parts are not
interchangeable, so matching numbers are stamped on
the C-link and on each coupling plate to ensure its
identification and proper assembly. You will save time
and trouble trying to match these parts if you
disassemble only one link at a time and clean, slush, and
reassemble it before disassembling another. The present
day slush, a preservative and lubricant, is a mixture of
40 percent white lead and 60 percent tallow by volume.
Other slush mixtures are being investigated to replace
the white lead. When you re-assemble a detachable link,
make sure the taper pin is seated securely. This is done
by driving it in with a punch and a hammer before
inserting the lead plug over the large end of the pin.
Detachable link toolbox sets contain tools, including
spare taper pins and lead plugs, for assembling and
disassembling links and detachable end links.
4-4
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