An anchor is a device which provides a mechanism for ships and boats to hold their position. It helps the vessels remain stationary during berthing and mooring at ports, or above an oil deposit.
To provide a pivot, the anchor grips on to any debris or rocks at the bottom of the sea. It can stabilize the vessel against waves during unfavorable conditions (like storms) and hence preventing bow slamming and green water loading. Green water refers to any water on the upper deck of the ship. Bow slamming is the result of the collision between water and the ship’s body because of its motion.
An anchor is a piece of heavy metal that is lowered to the bottom of the sea, ocean or lake to prevent a ship or boat from moving due to wind or water current.
Anchors can be permanent or temporary. Permanent anchors are rarely moved, need special service for maintaining and moving and are used to create a mooring.
Vessels may have one or more temporary anchors of different designs and weights.
An anchor chain is a heavy chain that connects the anchor to the boat or ship. The other end of the chain is secured to the ship’s structure by a rigging hardware which enables easy slipping of the chain to sea. The chain is heavy and abrasion resistant from coral, sharp rocks, or shellfish beds.
Large ships use only chain for connecting the vessel to the anchor, but smaller ones use a combination of rope and chain to save weight. A combination rode should be arranged in a way that the rope part suspends in water (and not be in contact with the sea bed).
A fender (or an aircraft tire fender) is a bumper that absorbs the kinetic energy of a boat or ship when colliding with other vessels and so it prevents damage to the vessels and berthing structures.
Fenders are typically made of rubber or plastic. Selecting the proper fender for a specific application depends on the vessel’s dimension, berthing structures, tidal variations and etc.