ANCHOR
Anchor, device cast overboard to secure a ship, boat, or other floating object by means of weight, friction, or hooks called flukes. In ancient times an anchor was often merely a large stone, a bag or basket of stones, a bag of sand, or, as with the Egyptians, a lead-weighted log. The Greeks are credited with the first use of iron anchors, while the Romans had metal devices with arms similar to modern anchors. The ordinary modern anchor consists of a shank (the stem, at the top of which is the anchor ring), a stock (the crosspiece at the top of the shank, either fixed or removable), a crown (the bottom portion), and arms, attached near the base of the shank at a right angle to the stock and curving upward to end in flat, triangular flukes. Other types of anchors include the patent anchor, which has either no stock at all or a stock lying in the same plane as the arms; the stream, or stern anchor, lighter than the regular anchor and used in narrow or congested waters where there is no room for the vessel to swing with the tide; and the grapnel, a small four-armed anchor used to recover lost objects. A sea anchor is a wooden or metal framework covered with canvas and weighted at the bottom; it is a temporary device used by disabled ships. Modern ships have several anchors; usually there are two forward and two aft. Formerly made of wrought iron, anchors are now usually made of forged steel.
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These modern anchors however must be handled properly
•ANCHOR TYPES
- Poor anchors : Danforth, LWT, Vicinay, non offshore type
- •Good anchors: Stevpris, Bruce FFTS, Bruce TS, Stevin, Flipper Delta
•The anchor must always be tested after running. Heave the winch to 1/3 BS and hold for 15 mins, then slack to working tension
•Depth of burial very important and soil type. The modern anchors have much larger fluke area and are also designed to bury very deeply
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