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method of cargo handling. Two booms are used. One
boom plumbs the hatch, and it is called the hatch boom.
The other boom is called the yard boom, and it is rigged
over the side so that it plumbs the dock or pier. Booms
are spotted in working position by hauling on the guys.
The cargo whips coming from the hatch and the yard
winches are run through heel and head blocks and are
shackled to the same cargo hook. The outboard guys
and preventers are balanced in proportion to the load
and in the working position of the boom.
Cargo whips are shackled to the cargo hook, and a
load is picked. The load is raised until the angle formed
by the whips is about 120 degrees. The outboard guys
and preventers are equalized by easing off the guy
tackles. As outboard guys and preventers are being
equalized, all slack is taken in on the inboard or
midships guys. It is a good practice, when originally
spotting the booms, to swing them slightly wider than
desired. When guys and preventers are equalized, the
booms will move inboard into position.
The winch controls for the yard and stay are usually
located so that one person can operate both winches and
have an unrestricted view of the hold. When you are
moving a load from the hold to the pier, the yard whip
is kept slack as the hatch whip hoists the load from the
hold and clear of the hatch coaming. Then, when you
heave around on the yard whip and pay out on the hatch
whip, the load is moved across the deck and over the
side. When the load is plumbed under the yard boom,
the hatch whip is slacked off and the yard whip lowers
the load to the pier.
Because topping and lowering booms are
dangerous evolutions, safety is always emphasized.
Personnel are cautioned to stay away from under the
booms while handling operations are in progress. The
deck should be kept as clear as possible of obstructions.
A clean deck provides the safest working condition.
As a Seaman, you should always watch for
discrepancies while a load is being moved, and keep
every part of the rig under constant observation. No
unnecessary personnel should be in the area. Those
involved with the operation must stay alert.
CARGO WINCHES
Winches designed for handling cargo consist of a
bedplate and side frames upon which are mounted a
horizontal drum shaft, drum and/or gypsy head(s),
reduction gearing, and usually the motor that drives the
winch. Figure 4-22 illustrates the components of a
typical winch. Drum winches are those with drums on
which the rope is wound for raising, lowering, or
pulling the loads. Gypsy winches have one or two
horizontally mounted gypsy heads around which turns
of line can be taken. Combination winches are drum
winches with shafts extended to take gypsy heads on
either side or on both sides. Preceding every winch
operation, operators should review all general operating
and safety instructions, among which are the following:
1. Always inspect the area around the winch, and
make sure there is a dry, safe place for the winch
operator to stand.
2. Inspect the rigging, making certain that the
standing rigging is taut and that the running rigging is
not fouled.
3. Inspect the equipment, making sure the clutch
levers are locked in place.
Although the engineering department is responsible
for maintaining winches, the winch operator and the
petty officer in charge must make certain that the
required maintenance is actually performed.
Coordination is essential for good winch operation.
After sufficient practice, winch operators should be able
to pick a draft from the hold and deposit it on the pier in
one smooth, constant motion. However, during the
early stage of training, the draft should be handled with
three distinct movements: hoisting, moving, and
lowering. In hoisting, one winch supports the entire
load and the other maintains slack. When the draft is
clear of the rail or coaming, it is carried across the deck
by both winches. This is called moving. When a draft is
in position to be lowered, the other winch supports the
entire load and the first whip is slacked. It is vital that
the right amount of slack be left in the nonworking whip
during the hoisting and lowering phases of the load's
cycle. If the whip is kept too tight, the draft will strike
against the side of the ship or the coaming of the hatch.
If the whip is allowed excess slack, loose turns will pile
up on the drum of the winch, and these must be rewound
before operations are resumed.
When cargo is being hoisted or lowered, swinging
should be avoided if possible. A wildly swinging draft
often results in damaged cargo and endangers the lives
of personnel working in the hold, on deck, or on the pier.
Swinging can usually be prevented in the hold or on the
pier by dragging or touching the draft until it is directly
under the head of the boom before hoisting.
Occasionally, a draft will start to swing athwartships
while being carried across the deck This swinging must
be stopped before the load can be landed. It can be done
easily with a little practice. When moving outboard, wait
4-24
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