TM 5-850-1
CHAPTER 12
CARGO HANDLING FACILITIES
12-1.
Cargo transfer between dock and vessel.
complished without lengthening or shortening the guys;
greater spotting ability, reduction of port time, and
a. Use of lighters.
greater safety than conventional burtoning system; and
(1) Application. In loading operations, cargoes
push-button control over topping lifts.
The
disadvantages include greater initial and maintenance
are transferred from the dock to lighters and then into
costs of vang posts and topping lift winches. These
vessels. In unloading the process is reversed. This
disadvantages are minor.
system is generally used where vessels are berthed
(c) Ebel rig. This rig is similar to the
offshore or where cargoes are brought to a berth by
Farrel rig but employs winches for both guying and
water rather than land transport.
(2) Equipment required. Transfer from lighter
topping. Vang posts are not used. The advantages of
the Ebel rig are: loads up to maximum boom capacities
to vessel usually employs ship's rigging or, where heavy
can be handled if doubling-up blocks are properly
lifts are required, a floating crane. For transfer between
employed; guying and topping are done completely with
lighter and dock, a dock crane, truck or railroad cranes,
pushbutton control (if winches are provided with "joy
or forklift trucks and ramps are used.
b. Direct transfer between dock and vessel.
stock" operated master switches, both motions can be
(1) Application. Where vessels are berthed at
controlled by one hand); greater spotting ability;
increased safety; reduction of port time; and
piers or wharves and where cargoes are delivered by
improvement in deck housekeeping.
truck or rail, direct transfer of cargo between dock and
(d) Jumbo boom. Practically all American
vessel may be made by using one of the systems set
cargo ships have one or more jumbo (heavy-lift) booms
forth below.
(2) Using ship's equipment.
located at strategic hatches on the vessel. These
This system
booms are stepped in a pedestal mounted along the
employs ship-mounted equipment, either alone or with
center line of the vessel. When not in use, they are kept
dockmounted equipment.
collared aloft. The advantages are greater over-the-side
(a) Conventional burtoning gear.
This
reach than conventional burtoning gear and high
system consists of a pair of ship's booms, each stepped
capacity (when backstays are used, capacities up to 60
at the foot of a kingpost, so that one boom is fixed fast
tons are common). The disadvantages are: greater
over the ship's hatch and the other over the dock (fig.
number of personnel required to operate the system;
slow in operation; boom must be slewed (used as
hydraulic, electric, or steam-operated winches and pass
swinging boom); limited maximum capacity; dangerous
through the boom head by means of fairleads (heel
operation (particularly when lowering heavy weights);
blocks, lizards, and head blocks), then married together
time required to ready gear from secured position, and
at a common point above the cargo hook. Modifications
additional space required to stow auxiliary gear when
and jury rigging of this gear is possible. The advantages
not in use.
include relatively simple design, economical first costs
(e) Shipboard crane.
The shipboard crane is
and maintenance, and elimination of highly skilled
another means of handling cargo with ship's gear. It has
operators. The disadvantages are: maximum load
been found, at least in certain trades, to be faster than
limitation, lack of flexibility (fixed booms are deficient in
the boommast/kingpost rigs.
The advantages are:
spotting ability); time loss in reporting or doubling-up to
increase in spotting ability; increase in over-the-side
maximum capacity, rigging dangers involved; and
reach when athwartship tracks are used; increase in
limited over-the-side reach.
safety about decks; and easier housekeeping. Deck
(b) Farrel rig. This system is similar to
watch officers at sea also find that a "forest" of masts,
conventional burtoning gears except that working guys
kingposts, and booms is eliminated when shipboard
are made fast to vang posts that are erected on deck,
cranes are used The disadvantage is that a highly
midship guy is nonexistent, and topping lift lead block
skilled operator is required.
assumes a position at or near the vessel's center line.
(f) House fall. Certain piers (particularly
Efficiency is improved by providing winches for the
those having narrow aprons or two-deck levels) are
topping lifts. The advantages are: topping or lowering
equipped with cargo masts that may be used in
ac-
combination with the vessel's regular cargo handling
gear. The
12-1
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