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Anchors
Sea anchors can be used by vessels of any size, from kayaks to commercial fishing
vessels[7]. While the purpose of the anchor is to provide drag to slow the vessel,
there are a number of ways this can be used. * The first, and probably most well
known use, of the sea anchor is to aid vessels in heaving to in heavy weather. A
boat that is not kept bow- or stern-on to heavy seas can easily be rolled by the
action of the waves. By attaching the sea anchor to a bridle running from bow to
stern, the boat can be held at any angle relative to the wind. This is useful in
sailboats in conditions too windy to use the sails to maintain a heading, and in
motor vessels that are unable to make sufficient headway to maintain steerage. *
Sea anchors also reduce the speed at which a vessel will drift with the wind. Often
sold as drift anchors or drift socks, sea anchors are used in fishing vessels to
hold them relatively stationary relative to the water to allow a certain area to
be fished, without having to use the motor. * A sea anchor can provide directional
control of a sailboat in the case of a steering failure. By towing a sea anchor
from a bridle off the stern, the direction of the boat can be controlled on a running
course. * A sea anchor can be used to control the speed of a sailboat, in cases
where delicate handling is required in high winds. * A sea anchor can be used behind
a towed vessel to maintain tension on the towing line, and prevent the radical side-to-side
motion exhibted by some vessels under tow. * Sea anchors may also be used as anchors
to allow warping of a vessel in deep water. A vessel disabled, in danger of closing
with land or other hazards can hold station, until the problem is fixed or help
arrives. “In moderate weather, before seas begin to break dangerously, parachute
anchors are effective at helping boats hold station. Fishing boats with hulls
designed to sit parallel to anchor lines, sit well to a para anchor, they are widely
used by squid fishers, to hold station while fishing.
Para anchors Many yachts yaw and sail at anchor, and even more on para anchors,
this phenomenon is called shearing. If a wave hits the bow in this shear cycle the
boat can be forced backwards, resulting in :- i)Damage to rudder. ii)Breaking rode.
iii)Rolling over. iv)Forcing water thru exhaust system under extreme pressure and
into the engine. In the trough of a wave/swell the para anchor rode goes slack,
the yacht will commence to yaw wanting to lie ahull, leaving it partially or totally
beam to sea with the possibility of being knocked flat or rolled.
Single buoy mooring (SBM) or Single point mooring (SPM) are loading buoys anchored
offshore and serve as a mooring point for tankers to (off)load gas or fluid products.
They are the link between the geostatic subsea manifold connections and the weathervaning
tanker. The main purpose of the buoy is to transfer fluids between onshore or offshore
facilities and the moored tanker. They are capable of handling any size ships, even
very large crude carriers (VLCC) where no facility is avaiable. Parts of single
buoy morring There are mainly four parts for the total buoying system, body of the
buoy, mooring and anchoring parts, product transfer system and other components.
Buoy body Buoy body is mainly static legs connected to the seabed, and a rotating
part above water level connected to an (off)loading tanker. These are connected
to each other by roller bearing, referred as "main bearing". The moored tanker can
freely weathervane around the buoy to a stable position due to this arrangement.
Mooring and anchoring parts Mooring arrangement is to fix the buoy to the seabed.
This requires predicted behaviour of the buoy for various wind, wave and current
conditions and various tanker sizes. This determine the optimum mooring arrangement,
and size of the various mooring leg components. Anchoring points are greatly dependent
on local soil condition. Mooring components * Anchors or piles to connect the mooring
to the seabed. * Anchor chain * Chainstoppers to connect the chains to the buoy
Hawser arrangement A tanker is moored to a buoy by means of a hawser arrangement.
International Oil Companies International Marine Forum (OCIMF) standards are available
for mooring systems. The hawser arrangement usually consists nylon rope, which is
shackled to an integrated mooring uni-joint on the buoy deck. At the tanker end
of the hawser, a chafe chain is connected to prevent damage from the tanker fairlead.
A load pin can be applied to the mooring uni-joint on the buoy deck to measure hawser
loads. Hawser systems use either one or two ropes depending on the largest size
of vessel which would be moored to the buoy. The ropes would either be single leg
or grommet leg type ropes. These would usually be connected to an OCIMF chafe chain
on the export tanker side [either type A or B depending on the maximum size of tanker
and the mooring loads]. This chafe chain would then be held in the chain stopper
on board the export tanker. A basic hawser system would consist of the following
[working from the buoy outwards]: Buoy Side Shackle and bridle assembly for connection
to the padeye on the buoy; Mooring Hawser Shackle; Mooring Hawser; Mooring Hawser
Shackle; Chafe Chain Assembly; Support Buoy; Pick-up / Messenger Lines; Marker Buoy
for retrieval from the water. Under OCIMF recommendations, the Hawser Arrangement
would be normally purchased as a full assembly from the Rope manufacturer. Product
transfer system The heart of each buoy is the product transfer system. From a geostatic
location, e.g. a pipeline end manifold (PLEM) which is located on the seabed, this
system transfers products to the offtake tanker. The Basic product transfer system
components are: * Flexible subsea hoses, generally referred to as “Risers” * Floating
hose string(s) * Product swivel, valves and piping Risers The risers are flexible
hoses and connect the subsea piping to the buoy. The configuration of these risers
can vary, depending on water-depth, seastate, buoy motions, etc. Product swivel
The product swivel is the connection between the piping in the geostatic part and
the rotating part of the buoy. Product swivels range in size depending on the size
of the attached piping and risers. Product swivels can provide one or multiple independent
paths for fluids, gasses and electrical signals or power. The swivels are equipped
with a multiple seal arrangement to minimise the possibility of leakage of product
to the environment. Floating hose string Floating hose string(s) connect the buoy
to the offloading tanker. The hose string can be equipped with a break away coupling,
to prevent rupture of hoses and subsequent oil spills. Other components Other Components
of SBM are: * Boat landing, providing access to buoy deck * Fendering to protect
buoy * Lifting and handling equipment to aid materials handling * Navigational aids
for maritime visibilty * Power provisions to enable valve operation, to power navigation
aids and for other equipments.
 CQR Galvanized Plow
Marine Anchors are drop forged high-tensile steel. CQR Marine Anchors hold in sand,
pebble, rock, grass, kelp and coral.
Genuine drop forged plough anchors. The CQR has immense holding power in sand, pebble,
rock, grass, kelp and coral. The drop forged, high-tensile steel makes it one of
the strongest anchors you can buy. The proven shank hinge design allows the anchor
to stay set during wind or tide changes.
- Drop forged high-tensile steel
- Holds in sand, pebble, rock, grass, kelp and coral
Also visit http://www.fortressanchors.com/
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