Ship bow anchors are divided into the following three categories according to their holding performance:
|
kind |
subordinate |
|
|
Ordinary anchor |
Stockless anchor |
Hall anchor, Speck anchor, Japanese JIS stockless anchor, Balt stockless anchor, US Navy stockless anchor, universal joint stockless anchor |
|
Stock anchor |
Naval anchor (with a horizontal bar, difficult to store, rarely used) |
|
|
High holding force anchor |
AC-14 anchor, Boll N and TW anchors, Delta anchor, Danforth anchor, lightweight anchor |
|
|
Super large holding force anchor |
The holding force is at least 4 times that of ordinary stockless anchors of the same quality |
|
Usually, according to the structural characteristics of the anchor, it can be divided into rotating claw anchor and fixed claw anchor, both of which can be divided into rodless anchor and rod anchor. This classification is not very strict.
1 ) Stockless swivel anchor ( CB/T 3983-2008 Stockless anchor)
The most common type of stockless swivel claw anchor is used as the bow anchor of most ships. Most of these anchors are suitable for storage in the anchor chain barrel. The commonly used types of stockless swivel claw anchors are as follows:
( 1 ) Hall anchor ( GB/T 546-2016 )
A typical common stockless anchor is usually used as the head anchor of a navigation anchoring system. The typical structure is shown in the figure below:
The disadvantage of the Hall anchor is that when the anchor is collected, the anchor claw faces one side of the hull and tends to slide along the hull, damaging the hull paint.
( 2 ) Speck Anchor ( CB 711-1976 )
This common stockless anchor is often used as a bow anchor in a sailing mooring system. Its basic performance is similar to that of a Hall anchor. Because the center of the anchor head is slightly lower than the shaft, the fluke and shank remain roughly aligned when the anchor is hoisted, preventing damage to the hull coating. The Speck anchor is particularly suitable for vessels with a prominent bow line, especially those with a bulbous bow.
( 3 ) AC-14 anchor and AC-14 balance anchor ( CB/T 3972-2005 )
The AC-14 anchor is commonly used as the bow anchor in navigational mooring systems. Its excellent performance, strong holding force, and adaptability to various muddy and sandy substrates, along with its excellent stability and ease of storage, make it widely used on large transport vessels and ships. The AC-14 balanced anchor is an improved version of the AC-14 anchor. Like the Speck anchor, the fluke remains vertical when hoisted.
( 4 ) Boer N -type anchor and Boer N -type balanced anchor ( CB/T 3221-2008 )
The Boll N -type anchor can be used as both the bow anchor of a navigational anchoring system and as a working anchor for engineering vessels. The Boll N -type balanced anchor is also an improved model, with the anchor claws held vertically when hoisted.
( 5 ) Boll TW anchor and Boll TW balanced anchor
The Boll TW anchor can be used as both the bow anchor of a navigational anchoring system and as the anchoring positioning system for engineering vessels. Compared to the Boll N anchor, it has a simpler structure, is easier to manufacture, and offers better performance.
( 6 ) Broad fin type Delta anchor.
This high-holding anchor is primarily used in mooring and positioning systems for engineering vessels. The broad-fin Delta anchor differs from typical stockless anchors in its construction. Its claws are sharper, with a smaller gap between the tips, allowing it to easily engage the soil when dragged. The wider lower portion of the claws acts as a stabilizer for stocked anchors and prevents entanglement in the anchor cable.
( 7 ) Other rodless rotary claw anchors
Common stockless swivel claw anchors used on foreign ships include: Balt stockless anchor, US Navy stockless anchor, universal joint stockless anchor, Japanese JIS stockless anchor. Their performance is similar to that of the Hall anchor.
Claw anchors are primarily used as anchoring systems for engineering vessels and can also serve as bow anchors. They typically have a stabilizing bar and longer, larger claws than stockless anchors.
( 1 ) Lightweight anchor ( LWT anchor) ( CB/T 4135-2011 )
A high-holding power anchor has a crossbar at the head of the anchor claw, which is both the rotation axis of the anchor and the stabilizing rod of the anchor, which can keep the anchor stable during turning and will not flip over.
( 2 ) Danforth Anchor
It is a high-holding anchor with a crossbar on the head of the anchor claw.
( 3 ) Stato anchor, Moorfast anchor and offshore drilling type II anchor
These are all cast steel high-holding power rod anchors used by foreign marine engineering vessels.
( 4 ) Steven series anchor
These anchors are developed by the Dutch company Freehaft Anchors for use in mooring systems for dredgers, crane vessels, pipe-laying vessels, and other offshore engineering vessels. They are all high-holding-power rod anchors.
The anchor claw and anchor handle of the fixed claw anchor are made into one piece, which is called the anchor body.
( 1 ) Naval anchor ( CB/T 4181-2011 )
The naval anchor is a rod anchor, the crossbar of which is set at the anchor shackle, forming a cross with the anchor claw. Once the anchor is grounded, once the force is applied, the anchor claw rotates and bites into the bottom with one end of the crossbar as the fulcrum.
The disadvantages of naval anchors are that they are difficult to store and cannot be put into the anchor chain barrel. When anchored, one of the anchor claws always remains on the bottom, where it can become entangled with the anchor line and even threaten ships passing over it, causing damage to the bottom of the ship. Naval anchors are rarely used unless there is a special need.
( 2 ) Single claw anchor
This anchor is shaped like a naval anchor with one claw removed, and its performance is similar to that of a naval anchor. When casting a single-claw anchor, you must hold the anchor head with the claw pointing downward. Slowly lower it to the bottom of the water, tightening the anchor line so the claw engages the bottom.
( 3 ) Four-claw anchor ( CB/T 24-1999 )
Generally, it has a smaller mass and is suitable for small boats.
( 4 ) Bruce SS Anchor
The fluke has three teeth and no crossbar. It is mainly used in mooring systems of marine engineering equipment.
( 5 ) Bruce TS Anchor
Evolved from the Bruce TS anchor, the fluke angle is adjustable to suit varying substrates. The fluke and shank provide combined grip, resulting in superior performance compared to the Bruce TS anchor. Primarily used in offshore engineering mooring systems.
( 6 ) Bruce FFTS Anchor
Although it evolved from the Bruce TS anchor, its shape has changed significantly, and the angle of the anchor claw is adjustable to suit different bottom conditions. It has greater holding power than the Bruce TS anchor and is primarily used in mooring systems for offshore engineering installations.
( 7 ) Steve Parish Anchor
Currently available in two models: MK5 and MK6 . Their large claw surface, plow-shaped shank, and claws with two sharp tines allow the anchor to penetrate deeper into the substrate, while shortening the drag distance required to achieve maximum grip. They are primarily used in mooring systems for offshore engineering installations.
( 8 ) Steve Shack Anchor
A variant of the Steve Parish MK5 anchor. The Steve Shaker anchor features a serrated shank and a specially reinforced fluke tip to withstand higher loads, enabling it to penetrate hard substrates. The Steve Shaker anchor is primarily used in offshore mooring systems.
( 9 ) Other forms of anchors
The above are all drag anchors, and there are also some special forms of anchors such as mushroom anchors, hemispherical cement anchors, gravity anchors, and arrow embedded anchors, which are mainly used for permanent fastening of moorings.
There are also anchors for permanent mooring systems, such as pile anchors, suction anchors (negative pressure anchors), normal bearing anchors, plate anchors, etc.
