The Auxiliary Role of Anchor in Mooring

The anchor plays a major role in anchoring (fixing a ship with an anchor), but in mooring (usually referring to fixing a ship to a wharf, buoy or other fixed structure with a mooring line), it usually does not directly participate in fixing the vessel.

However, in specific types of mooring operations or under certain circumstances, anchors may also play an auxiliary role:

1. Auxiliary positioning and stabilization (beside the wharf/berth) :

Temporary berthing/waiting for a berth: When a vessel is waiting for a berth, it sometimes anchors in the waters near the pier to temporarily secure its position and prevent it from drifting and colliding with the pier or other vessels.

Limit bow swing (especially for small vessels) : When mooring at the pier, if the wind or current is strong or the berth is long, the bow may swing left and right. At this point, dropping an anchor (referred to as a bow anchor) on the outside of the bow (the side away from the dock) and tightening the anchor chain can help limit the swing range of the bow, allowing the vessel to approach the dock more stably.

Severe weather/Special Operations: When mooring at the pier during severe weather conditions such as typhoons or strong currents, to enhance additional safety and prevent the vessel from drifting out of control in case the mooring ropes break, an extra anchor (usually the bow anchor) is sometimes used as a backup fixed point.

Offshore/open water mooring: When a vessel needs to be mowed at a buoy or single-point mooring system far from the wharf, anchors and mooring cables are sometimes used in combination. For example:

The stern is tied to the buoy with a cable, and the bow is anchored to form a "two-point mooring", which increases stability.

Or, when designing the mooring system, the anchor chain (connected to the anchor on the seabed) is included as part of the entire mooring structure.

2. Control the bow direction (mooring in a single buoy) :

When a vessel is moored on a single buoy (usually at the stern or in the middle of the ship), the bow can rotate freely. To control the direction of the bow (for example, to keep it always facing the wind or current for better stability, or to prevent the bow from facing a dangerous direction), an anchor can be dropped at the bow, and the direction of the bow can be controlled by adjusting the length of the anchor chain.

The core difference: Anchoring vs. Mooring

Anchoring: It mainly relies on the bottom-grasping force generated by the anchor claws embedding into the seabed (as well as the frictional force between the anchor chain/cable and the seabed) to fix the vessel. The anchor is the main fixing device.

Mooring: It mainly relies on mooring ropes (such as nylon cables, steel cables, etc.) to be connected to fixed structures like pier piles, buoys, and mooring buoys at the wharf to secure the vessel. These fixed structures provide the main binding force. Anchors in mooring are usually auxiliary or backup roles.