英语原文共 18 页，剩余内容已隐藏，支付完成后下载完整资料
1 Overview of Anchor and Mooring Gear
1. Storage part of the mooring drum
2. Pulling section of the drum (working part)
3. Brake band
4. Gear box
5. Electro-hydraulic motor
6. Warping head
7. Chain in the gypsy wheel
8. Dog clutch
10 Hawse pipe
11. Spurling pipe
12. Chain locker
13. Chain stopper with security device
14. Guide roller
16. Guide roller
18. Hatch to chain locker
2. Anchor equipment
The purpose of the anchor gear(or ground tackle) is 10 fix the position of a ship in shallow water by using the sea-bed. Reasons for doing so can be:
-the ship has to wait until a berth becomes available
-to load or discharge cargo when a port does not have a berth for the ship, either temporarily or permanently.
-to help with maneuvring if the ship does not have a bow thruster and/or no tugboats are available
-in emergency cases to avoid grounding
2.2 Legal requirements for the anchor and mooring gear
Each bow anchor needs to be provided with a certificate, issued by Class, based on type, materials used, weighing and testing.
The same is applicable to chain cables. A certificate for the anchor and mooring equipment is only issued after all the requirements of the Classification Society are met. The original certificate has to be on board. The table below indicates equipment numbers used to determine the minimum weights and dimensions of the anchors, chains, ropes, etc. The equipment number can be found on the Midship Section drawing.
Anchors are the final safety resource of a ship. From ancient times, the men using them had a stone on a sling to keep the boat in position. Later developments show combinations with wood, ending in the stock anchor (fisherman#39;s anchor) with wooden stock. When propulsion or steering
fails, the seafarer has to rely on his anchoring equipment. It is therefore of utmost importance that this equipment is in good condition. A regular check of the condition of the anchor itself, the crown, anchor shackle, the chain cable, windlass, brake band and anchor securing arrangements is the responsibility of the master.
In general, ships have two bow anchors and sometimes a stern anchor. There are two bow anchors for safety. Under normal circumstances one anchor is sufficient, but under severe weather conditions or in strong current both anchors may be needed. Also, if one anchor fails, the second anchor is a back-up. Normally a ship is not allowed to sail from any port when one anchor has been lost.
The Classification Bureau may allow departure under the condition that replacement is carried out at the earliest opportunity and that the vessel takes additional tug assistance leaving and entering port.
The stern anchor is used to prevent ships (coastal trade liners, for example) from rotating due to tidal changes in a river current.
Anchors can be:
-HHP anchors (high holding power)
-SHHP anchors (super high holding power)
Common conventional anchor types are Spek, Hall, Union and Baldt.
Spek anchors have the advantage of being fully blllanced.
A fully balanced anchor has the following advantages:
-an anchor recess that completely
-envelops the anchor, can be used
-the shell cannot be easily damaged during heaving when the anchor flukes leave the water vertically
Accepted HHP anchors are ACI4,Pool and Danforth. CQR lind Plowtype anchors are only used on small craft. Various copies of accepted types are made all over the world.
A fully balanced anchor means that when the anchor is being weighed,lifted from the seabed into the hawse pipe with the flukes verticlll, the weight of the head serves as being a counterweight. Such an anchor is never fouled, i.e. with the flukes pointing into the ship#39;s shell.
The conventionlll type is still used a lot and serves as a standard for newer types of anchors (see table).
Conventional anchors are always cast. Newer types, such as Pool, can also consist of plates (or other components) thllt are welded together. If the flukes are hollow, they tend to be more resistant towards bending forces.
The crown plate ensures that the flukes of the anchor penetrate the sea floor. In certain types of anchors, flukes prevent the anchor from burying itself too deeply in the sea bottom.
The navy uses a specially developed HHP anchor with an open crown