Balanced vs. Unbalanced Anchors: Which One is Right for Your Vessel?

Welcome to a new edition of our Not-So-Trivial Questions column!

At Posidonia, we know that even the simplest questions can reveal essential aspects of the maritime sector. That’s why we provide practical answers to help professionals better understand the world of mooring and towing.

Understanding the Difference Between Balanced and Unbalanced Anchors

In nautical terms, the distinction between a balanced anchor and an unbalanced anchor is not a formal classification but rather a way to describe how the flukes move relative to the shank during retrieval and deployment. The movement of the flukes is dictated by the anchor’s center of gravity.

Comparison of balanced and unbalanced anchors showing fluke and shank alignment differences for yachts and ships.

Advantages of Unbalanced Anchors for Specific Hull Configurations

Unbalanced Anchor: Initially, all anchors were unbalanced. An anchor is considered unbalanced when the center of gravity of the fluke is positioned above the shank’s pivot point. This causes a moment that misaligns the flukes with the shank, leading them to tilt forward or backward during deployment and retrieval. In certain hull configurations and seabed conditions, an unbalanced anchor can be advantageous, facilitating mooring maneuvers and/or chain pipe entry.

Why Balanced Anchors Became the Industry Standard in Yachting

Balanced Anchor: In the 1980s and 1990s, the need arose to prevent the flukes from touching the vessel’s hull during retrieval, deployment, and stowage—especially in the yacht sector. A balanced anchor is defined as one where the center of gravity is positioned below the shank’s pivot point, creating a moment that keeps the flukes aligned with the shank in a perpendicular position relative to the water surface.

Today, this type of anchor has become the industry standard in the yachting sector.

Our range of balanced and unbalanced anchors includes the PTW+®, PTW®, HV®, and Compact models. Here’s an overview of each:

PTW+® Anchor: A Super High Holding Power (SHHP/VHHP) anchor, ideal for yachts and commercial vessels. Manufactured using high-strength certified steel, it offers a 50% weight reduction compared to conventional mass anchors while maintaining the same holding power.
PTW® Anchor: A versatile High Holding Power (HHP) anchor, suitable for yachts and ships. Made from high-strength certified steel, it provides a 25% weight reduction compared to mass anchors without compromising holding capacity.
HV® Anchor: Known as the "queen" of welded anchors, the HV® provides exceptional performance across all seabed types. Its fluke design, made from two bent and welded steel plates, forms an arrow-shaped tip, ensuring optimal seabed penetration. HHP certified, this anchor allows for a 25% weight reduction compared to mass anchors or can be supplied with increased weight while maintaining the same shape, thereby further improving its holding capacity.
Compact Anchor: Designed by Posidonia to meet the needs of vessels with narrow hawse pipes requiring heavy anchors. Its compact design and HHP certification enable a 25% weight reduction compared to mass anchors while ensuring high holding power.

All our welded anchors can be customized. They can be supplied with a 10% shank reduction and are certified by leading classification societies.

Additionally, all our anchors are available in various finishes and, for specialized vessels, can also be supplied in a low magnetic permeability version.