The anchor is an indispensable device to ensure the safety of the ship. The anchor mainly has an anchor crown. Pins, anchors, anchor shanks, anchors (also called crossbars or stabilizer bars) and anchor shackles.

Anchor throwing method

Ship anchoring is a common method of parking. The process is roughly as follows: the anchor connected by the anchor chain or the anchor cable is thrown into the water and landed in the soil, and the grip force generated by the anchor is consolidated with the bottom of the water, and the ship is firmly tied in a predetermined position, according to Different waters, meteorological conditions, operational requirements, and anchor throwing methods are different. Commonly used methods include first anchor, tail anchor, and head and tail anchor.

1, the bow of the anchor

The bow is anchored, and there are two types of throwing single anchors and double anchors. Under normal circumstances, only a single anchor can be used to fasten the vessel. Only when the wind and waves are particularly large and the anchorage is large and narrow, the double anchor is thrown. When the bow is anchored, the hull is subjected to the least external forces such as wind, water flow and wave impact. Therefore, this method is the main way of anchoring and anchoring, and it is also the main reason why the main anchor is placed at the bow. Usually only a first anchor is provided on the ship and on the fishing boat. In addition, any ship is equipped with two main anchors on the bow of the ship. When the length of the ship reaches a certain level, an alternate main anchor, also known as a wind-resistant anchor, should be provided on the ship.

2, the stern anchor

The stern anchor is mostly used for inland river boats and landing boats. When the river trade vessel berths downstream to the water, in order to ensure safety and avoid turning the head, the stern anchoring is often used. In the operation of landing the ship back to the beach, with the cooperation of the host, relying on the pull of the anchor machine to pull the ship on the beach to the beach.

3, the first tail of the anchor

If you want to make the ship that is parked always on the side of the ship, facing the wind direction, the first and last anchoring method is adopted. The method of first and last anchoring is generally to throw the main anchor from the direction of the top wind, and a cable is connected from the stern of the ship to the main anchor chain that has been thrown out of the ship's outboard, and then some main anchor chains are released. Another method Yes, after the first anchor is thrown, the tail anchor is thrown from the tail. The tail anchor is usually carried out by a small boat, and the tail anchor is generally smaller than the main anchor, which is about 1/3 of the main anchor.

Type and characteristics of anchor

There are many types of anchors, which are roughly divided into four types: rod anchors, rodless anchors, large claw anchors and special anchors, and more than ten kinds of anchors.

1, there is a pole anchor

The anchor with the crossbar is a rod anchor. This type of anchor is characterized by an anchor claw biting into the soil. When the anchor is dragged on the seabed, the crossbar can prevent the anchor claw from tipping over and stabilize. Among the anchors are naval anchors, layered anchors, single-claw anchors and Japanese anchors.

Naval anchor: It is the most used rod anchor used in the oldest, also known as ordinary anchor. This kind of anchor has a large grip and can hold all kinds of soil firmly, but it is inconvenient to retract. Modern large ships have not been used as the main anchor. They are only used as main anchors on sailboats and small inland river boats, naval rescue boats and engineering ships. Can be used as a job positioning anchor.

Layered Loan Anchor: A naval anchor that can be rotated by an anchor. In use, when one claw enters the soil, the other claw can be transferred to the anchor handle and pressed tightly. This kind of anchor is more convenient to use than the naval anchor, but the grip is smaller than the naval anchor, and only one bolt is used to connect the anchor handle, which is poor in safety. Therefore, it can only be used on sailing boats and river boats. The anchor weight is generally no more than one ton.

Single-claw anchor: Similar to a naval anchor, it has only one claw, but it is larger in size. This type of anchor has a larger claw force than a naval anchor. Positioning anchors for a variety of engineering vessels, which are commonly used in dredgers to ensure that the vessel does not move during dredging operations.

Japanese anchor: It is a kind of double-claw anchor used on Japanese fishing boats. The crossbar is fixed under the anchor crown, which not only maintains the advantage of large grip, but also facilitates collection.

2, no rod anchor

Without the crossbar, the two-claw anchor that the anchor can rotate is a rodless anchor. The characteristics of this type of anchor are that the two claws are simultaneously bitten into the soil during work, the stability is good, the adaptability to various soils is strong, and the collection is convenient. Rodless anchors have developed rapidly and have evolved from the first generation to the third generation. Commonly used rodless anchors are mainly Hall anchors, Sbeck anchors, AC-14 anchors and DA-1 anchors, as shown in Figure 4.

Hall Anchor: The Hall Anchor is the first generation of modern standard rodless claw anchors. The anchor is simple to make, convenient to collect, has a large grip, and has good grip. It is the object of choice for the main anchor of large and medium-sized ships. China likes to use this kind of anchor.

Sbeck Anchor: It is an improved version of the Hall anchor. Its structural feature is that the anchor crown is equipped with anchor plates and ribs. Therefore, the claws of the anchor are easily turned to the ground, the stability is better, and the outer panel of the ship is not scratched during collection.

AC-14 anchor: The second generation called the rodless anchor. The anchor crown is wide, the anchor claws are thick and long, and have longitudinal edges. This kind of anchor has a large weight and a large grip. Good stability. It is often used as the main anchor for large container ships, car carriers and super-large tankers. It is commonly used in Europe and the United States and Japan.

DA-1 type anchor: The AD-1 type anchor is called the third generation rodless anchor and is the most stable and most advanced anchor in the world. The anchor crown is wide and the end is triangular, and the claw is long. It is an inverted V-shape formed by two inclined faces. The distance between the two claws is small. The anchor has the most suitable angle of the biting, and the biting area is large. The utility model has the advantages of large grasping force, good grasping property, strong stability and convenient collection. Since the DA-1 type anchor is almost entirely composed of a straight inclined surface, the anchoring is less when the anchor is anchored, and the washing is convenient, and the Japanese shipbuilding industry considers that the anchor is the most ideal. The most promising anchor.

3, high holding power anchor

The high-grip anchor is actually a kind of rod-claw anchor, which is called a large-grip anchor because it has a large weight-to-weight ratio. The characteristics of this kind of anchor are that the anchoring claw has a large area of ​​the soil, and the bottom of the grip is deep and many, and the grip is particularly strong, but the anchor claw is easy to be pulled and the collection is inconvenient. Among the high-grip anchors are Markov anchors, Danfor anchors, speedboat anchors, Schrodinger anchors, and Staro anchors.

Markov anchor: The structure of the Markov anchor is characterized by a wide anchor and a stabilizer bar on the outside of the middle of the claw. In order to prevent the rock from catching the anchor, the claw cannot be rotated, and the inside of the claw is curved. Markov anchors are available in both welded and cast forms. Both forms of anchors are commonly used in China.

Danfor anchor: Similar to the Markov anchor, except that the stabilizer bar is placed on top of the anchor. The weight-to-weight ratio of such an anchor is particularly large, about three times that of a naval anchor.

Schlininger anchor: Its structural feature is that the stabilizer bar is designed to be inclined and the distance between the two claws is large to prevent the anchor claw from being caught by the gravel.

Speedboat anchor: As the name suggests, it is the anchor used in the speedboat. Its structural feature is that the two claws are relatively close, the crossbar is mounted on the outside of the claw, and the anchor crown is small. This kind of anchor has a very strong grip, but the crossbar is easy to bend.

Staro Anchor: It is a new type of high-grip anchor with a weight-to-weight ratio of 15-20. The anchor claws are particularly wide and the crossbar is located at the anchor crown and is welded. Unlike other anchors, there is a detachable wedge to change the angle at which the jaws rotate.

4, special anchor

The shape and use of special anchors are different from ordinary anchors. Mainly refers to permanent mooring anchors used for buoys, barges, floating docks, etc.; ice anchors used on icebreakers and floating anchors used on sailboats and boats.

Loss and prevention of anchor

It is a common occurrence that the ship loses the anchor and the ship loses the propeller cap. The anchor is connected by the anchor shackle and the anchor chain, so there are two situations in which the anchor is lost. One is caused by the anchor shackle, and the other is caused by the anchor chain.

1. Anchor shackle caused

The anchor shackle is made of steel and is forged or welded with a pin on it. The anchors are generally hung on the sides of the ship's head. Due to the impact of heavy winds and waves and the impact during retraction, the bolts may loosen and disengage. When the pin is disengaged, the loss of the anchor is caused.

2, caused by the anchor chain

Due to the long-term use of the anchor chain, the wear and tear is serious. When the anchor is just thrown on the hard bottom, and the anchor speed is too fast, the anchor will be broken and the anchor will be lost. The loss of the anchor can be prevented. Before the ship sails, the anchor shackle should be carefully checked. If it is loose, it should be disposed of in time. The anchor chain shall be inspected and replaced on time according to the inspection requirements of the ship. As long as the above two points are achieved, and the speed is appropriate when anchoring, the anchor will not be lost.

With the development of science and technology and the shipbuilding industry, new types of anchors will continue to emerge, providing a reliable guarantee for the safety of ships.

Anchoring:

When the anchor is at a certain distance from the ship, the anchor chain is inclined, and the tension of the ship can be fixed. So the first thing to do when anchoring is to solve this problem.

The anchoring machine is tightened to tighten the anchor chain, and the ship moves in the direction of the iron anchor. When the anchor link is nearly vertical, the anchor is retracted.

If the front and rear anchors are lowered, first relax one anchor chain, tighten the other anchor chain, pick up an iron anchor, and then another iron anchor.