There are many kinds of marine anchors. According to the different structures and uses, the ship anchor can be classified into a stocked anchor, stockless anchor, high holding power anchor and special anchor. The bow anchor adopted by the merchant ship is a stockless anchor, while the stern anchor sometimes adopt a stocked anchor or a Danforth anchor.
1. Stocked anchor
The anchor has the advantages of a simple structure, large holding power to weight ratio and high grip stability, but it has inconvenient anchoring operation and storage with an anchor stock. Therefore, this anchor should not be used as a bow anchor for commercial ships, suitable as a stern anchor, generally used for small boats.
2. Stockless anchor
It is also known as the hall’s anchor and the generally adopted stockless anchors
for merchant ship are Hall anchor and Spek anchor. The anchor fluke and anchor rod can rotate at a certain angle and is a stockless type. The holding power to weight ratio is 2.5 to 4 and the maximum is up to 8. The anchor has a simple structure, throwing anchor operation and storage conveniently, so it is suitable for the bow anchor with the widest applications. But it also has the disadvantage of a small anchor grip. The Hall anchor is the earliest used type and the Spek anchor is an improved type of Hall anchor, which has the advantage that its anchor fluke can be naturally upward.