A marine anchor is an indispensable device for ensuring ship safety, which is used to stabilize the ship when the ship is not parked or mooring without a buoy. When some ships enter the berthing area, the anchor will be thrown into the water for steady berthing.
Why Marine Anchor Used For Smooth Boat Berthing
How does an anchor can stabilize a ship? Because the anchor is sinking to the bottom, which will generate a huge grasp force, and the gravity of the marine anchor chain itself is large enough. The ship will be fixed.
When the ship needs to be temporarily moored, the ship anchor will be thrown out. An extra length of the anchor chain will be put to more close to the bottom of the sea. As the anchor is slowly sinking, the fluke of the anchor will have contact with the underwater bottom. At the same time, the anchor fluke under the seabed will be subject to a horizontal tension force. Under the dual role of tension force and gravity, the anchor is slowly inserted into the seaside, which is getting stronger and ensures stable berthing and water safety.
The anchor chain is also very important, the total weight of the anchor chain is much larger than the anchor. The length or the anchor chain is several times larger than the water depth, and there is a relatively long anchor chain is lying on the water bottom, and the underwater also has a great friction resistance to the anchor chain.
How To Select The Anchorage
When the boat anchor is thrown, the boat cannot be started and control normally and will be drifting everywhere, so a safe and suitable anchorage should be selected before throwing, surveying its topography and choosing the appropriate mooring area.
The selected anchorage ground should have the appropriate water depth, no large waves, good shielding.
1. When the anchor station is selected in the deepwater area, the largest water depth of the anchorage generally does not exceed 1/4 of the total length of the anchor chain. Otherwise, the anchorage grasps will be affected.
2. The geological and terrain of the anchorage should be good, with moderate soft and hard bottom and clayey seabed, so that the anchor grasp force is better.
3. It is best that the terrain around the anchorage can provide a natural barrier to the vessel, which makes the anchor to get better into the underwater bottom, becoming more secure, so that the ship has stable berthing.
4. The anchorage should also be away from the channel, the water area and there is no cable below.
Main Types Of Marine Anchor
1. Danforth anchor
Danforth anchor is the first generation of high holding power anchors and belongs to stockless anchors with a large grasping weight ratio and rodent area. The gripping bottom is deep and numerous, and the grasping force is extremely large. But the anchor fluke is easily broken and the storage is inconvenient, not suitable for transportation boats.
The Bohr anchor is also called TW type anchor or N type anchor. It has more than 2 times the holding power of the conventional anchor of the same weight. The anchor has large flat flukes made out of high tensile steel plate material. It is used as a bow anchor when sailing.
It is designed to fit into small anchor pockets on modern ships and the hollow flukes are welded from two plates to create strong anchoring performance under various circumstances.
Hall anchor is also known as the mountain anchor, which is a stockless HHP anchor, free to rotate, inclined to stock. The anchor head and the anchor fluke are a whole casting. When a lying anchor is contacted with the underwater bottom through any side of the anchor, the resistance generated by the anchor head strip friction discharge soil is forced to generate the grasp force of the anchor.
The Spek anchor is a modified Hall anchor. Plate and reinforcing rib are installed at the anchor crown. Therefore, the fluke of the anchor is easy to turn to the ground with high stability and when stores the anchor, the anchor fluke naturally facing up. Moreover, in contact with the boat shell, it will not damage the boat shell plate.
AC-14 anchor is a stockless HHP anchor with a wide anchor crown, thick and long flukes, and longitudinal ribs. It is available in a self-colored finish or in a galvanized finish. Its design provides excellent weight to performance ratios. The lighter weight which is 25% weight reduction compared to conventional anchors and high holding power makes it good stability and then it is commonly used as the main anchor on large container ships, supertankers. It has an excellent performance in a variety of soils.