speeds in each direction with adequate torque in hoist
Destroyer Anchor Windlass
directions and dynamic braking in all lowering points.
For warping, the control characteristics are substantially
The anchor windlass installed aboard destroyers
identical in both directions. A single controller master
consists of a two-speed motor directly connected
switch is provided and located on the deck adjacent to
through reduction gears to a vertical shaft. A capstan
the windlass.
and a wildcat (fig. 5-21) are mounted on the vertical
shaft. The capstan and the wildcat are located on the
Electric-Hydraulic Anchor Windlasses
weather deck; the electric motor and the across-the-line
starter are located in the windlass room on the next deck
Electric-hydraulic anchor windlasses are
below. The windlass is designed to operate in both
particularly adapted for anchor handling because of
directions to raise or lower either the starboard or port
varying load conditions and their wide range of speed
anchor.
and torque characteristics. The hydraulic drive was
CONSTRUCTION.-- The windlass is driven by a
developed to overcome all the operating and installation
two-speed (full speed and one-quarter speed),
objections inherent with either steam- or
three-phase, 440-volt, 60-hertz motor connected to the
direct-electric-driven windlasses. The electric-
reduction gear by a controlled torque coupling. The
hydraulic windlass drive is similar to the electric drive
controlled torque coupling is provided to prevent undue
with one exception. Instead of having the electric motor
stresses when the anchor is being housed. When the
coupled directly to the reduction gearing, the power is
anchor is housed, the drum master switch must be
transmitted from the electric motor through a variable
shifted to the low-speed position before the anchor
stroke hydraulic transmission. This obtains a wide
enters the hawsepipe.
range of output shaft speed.
An electric brake is mounted just below the
The electric motor for a hydraulic windlass is
controlled-torque coupling. This brake will release
usually a single-speed, squirrel-cage type. Electric
when power is applied. It will set when power is
control is required only for light starting duty, as the
disconnected or fails. If power fails, the electric brake
motor is started in a no-load condition. The motor is
is designed to stop and hold 150 percent of the rated load
direct coupled to the pump unit of the hydraulic motor
when the anchor and chain are being lowered at
unit, B-end, through piping. The B-end is coupled to a
maximum lowering speed.
suitable reduction gear that drives the windlass shaft. To
determine windlass speed, you vary the stroke of the
The wildcat is designed to hoist one anchor and 60
pump A-end. This is done by control handwheels,
fathoms of 1 1/4-inch dielock chain in not more than 10
located on the weather deck and at the pump. These
minutes on the high-speed connection without
handwheels also control the direction of rotation of the
exceeding the full-load rating of the motor. On the
windlass and are suitably marked. The stroke at which
low-speed connection, the wildcat is designed to hoist
the A-end is set determines the quantity of hydraulic
the anchor and 60 fathoms of chain without overloading
fluid delivered to the B-end, which, in turn, determines
the motor. Also, on the low-speed connection, the
the speed at which the B-end rotates.
wildcat exerts a pull on the chain at least three times that
required to hoist the anchor and 60 fathoms of chain.
The power plant of a typical hydraulic windlass
installation for large combatant or auxiliary vessels has
The capstan is designed to heave a 6-inch
two units. Each unit comprises a constant-speed,
circumference manila line at a speed of 50 feet per
horizontal, squirrel-cage, electric motor driving a
minute with a line pull corresponding to the full-load
variable stroke hydraulic pump through suitable
motor torque.
reduction gearing. The electric motors have magnetic
brakes designed to hold 150 percent of the motor-rated
The capstan head is keyed directly to the drive shaft,
torque. They are set on loss of power to prevent the
while the wildcat is connected to the drive shaft through
anchor dropping. The power units are arranged, port
a driving head and a locking head. The wildcat is keyed
and starboard, in the windlass room. Normally the port
to the driving head, and the locking head is keyed to the
unit drives the port windlass half, and the starboard unit,
drive shaft. Vertical blocks sliding in slots in the locking
head are raised (by the locking handwheel) into slots in
the starboard half. However, transfer valves are
provided in the oil lines that, when properly set, allow
the driving head to connect the two heads. The
mechanism is called the locking gear. The wildcat and
the port power unit to operate the starboard windlass,
and vice versa.
sleeve run free on the same shaft until connected to the
5-34
