Mooring Bollards Types and Applications

Struggling to select the right mooring bollard? Choosing incorrectly from the many types and sizes available can risk safety and bust your budget. Let's make it simple.

Choosing the right mooring bollard involves matching its type (like T-head, Bitt, or Cleat) and size, defined by its Safe Working Load (SWL), to the vessel, mooring angles, and quay design. Material selection, such as cast steel or iron, is also critical for durability and cost-effectiveness.

Sorting through all the options can feel overwhelming. I remember when I first started, the sheer variety seemed endless. But over the years, working with clients like Tommy, a seasoned distributor in South Korea, I've learned to break it down into simple, manageable pieces. Understanding these core differences is the first step to ensuring a safe and efficient mooring system. Let's look at the most common types you'll encounter.

What are the different types of mooring bollards?

Picking a bollard feels confusing with so many regional names and designs. This uncertainty can lead to specifying a type that's either over-engineered or simply wrong for your port.

The most common bollard types include T-head, Bitt (Single and Double), Pillar¹, Tricorn², and Cleat³s. Each is designed for specific mooring line angles and vessel sizes, with certain types being more popular in different regions of the world due to historical standards and practices.

When I work on a project, the first thing I do is identify the application to narrow down the choices. A small yacht marina has very different needs than a major commercial port handling massive container ships. The T-head bollard⁴ is a great example of a versatile, modern design. It provides a very high strength-to-weight ratio, making it one of the most cost-effective and widely used options globally. It’s a huge improvement over older, heavier standards. However, different regions have their own trusted designs.

Key Bollard Types and Their Regions

Bollard Type	Common Region(s)	Typical Use Case
T-Head	Global	General purpose, various vessel sizes
Single/Double Bitt5	North America	High line angles, vessel mooring
Tricorn	Baltic Sea Region	Handles multiple mooring lines at once
Pillar	Global	General use, simple and robust
Cleat	Global	Small vessels, yachts, and workboats
Kidney6	Europe	Where multiple lines are needed

Understanding these regional preferences is important for distributors like Tommy, as it helps him align his stock with local demand while also introducing more efficient global standards like the T-head to his clients.

What is a mooring bollard used for?

You see them on every dock, but do you know their exact function? Misunderstanding their purpose can lead to unsafe mooring practices that endanger vessels, cargo, and personnel.

A mooring bollard is a short, strong post fixed to a quay, pier, or ship deck. Its primary purpose is to provide a secure anchor point for mooring ropes, holding a vessel safely in place against the forces of wind, current, and waves.

In my early days at a fender factory, I saw firsthand that a bollard is more than just a piece of metal; it’s a critical safety device. The entire mooring system, from the ropes on the vessel to the fenders on the quay, relies on the bollard to hold everything together. As a supplier, I always emphasize that the bollard must be strong enough to handle the maximum expected load from the vessel it will serve. This is what we call the Safe Working Load (SWL)⁷. The bollard secures the vessel, preventing it from drifting away from the berth, which allows for the safe loading and unloading of cargo and the safe embarkation and disembarkation of passengers and crew. Without this simple but vital piece of equipment, port operations would be impossible.

Primary Functions of a Bollard

• Vessel Security⁸: It's the fixed point that keeps the ship stationary.
• Force Absorption⁹: It must withstand constant and sudden loads from mooring lines.
• Operational Hub: It's the connection point between the ship and the shore.

Every time I supply a set of bollards, I'm reminded that we are providing the final link in the safety chain that keeps billions of dollars of goods and countless people safe every day.

What size is a mooring bollard?

Choosing the wrong size bollard is a common and costly mistake. An undersized bollard can fail catastrophically, while an oversized one is a waste of money and resources.

A mooring bollard's size is not defined by its physical dimensions but by its Safe Working Load (SWL)⁷, measured in tonnes. Sizes range from 1-tonne SWL for small cleats up to 300-tonne SWL or more for bollards used in large commercial ports.

The SWL is the most important number. It tells you the maximum force the bollard can safely handle. I've seen projects specify bollards based on old drawings without recalculating the loads for modern, larger vessels. This is a huge risk. The required SWL is determined by factors like the vessel's displacement, wind and current conditions, and mooring angles. For instance, a small cleat for a private yacht might weigh only a few kilograms and have a 1 or 2-tonne SWL. In contrast, I recently supplied a set of bollards for a major LNG terminal. Each had an SWL of 200 tonnes and weighed over 7,000 kg, made from high-grade cast steel¹⁰. The physical size grows with the SWL, but the SWL is the true measure of its "size" and capability.

Factors Determining Bollard SWL

• Vessel Size¹¹: Larger ships exert greater forces.
• Environmental Forces¹²: Wind, waves, and currents add significant load.
• Mooring Pattern: The number and angle of mooring lines affect load distribution.

Always perform a proper mooring analysis¹³ or consult a qualified engineer to determine the correct SWL for your application. This ensures both safety and cost-efficiency.

What are the three types of mooring?

Thinking that all mooring is the same can limit your options. Different situations require different approaches to secure a vessel, and the bollard is a key part of that system.

The three principal types of ship-to-shore mooring are alongside mooring, Mediterranean mooring¹⁴, and Baltic mooring¹⁵. Each method uses a different configuration of mooring lines and requires specific placement and types of bollards on the quay to be effective.

Each mooring style solves a unique problem, primarily related to space and vessel type. I've supplied bollards for all three setups.

1. Alongside Mooring

This is the most common method you see in commercial ports worldwide. The vessel is moored parallel to the quay. It uses a series of lines—head lines, stern lines, breast lines, and spring lines—to keep the ship from moving forward, backward, or away from the dock. This setup requires a series of bollards spaced along the length of the berth.

2. Mediterranean Mooring

This method is used where quay space is limited, often in crowded harbors or marinas. The vessel berths stern-to the quay, with anchors dropped from the bow to hold it in place. Mooring lines are run only from the stern to bollards on the quay. This requires fewer bollards but strong ones, as the stern lines take a significant load.

3. Baltic Mooring

This is a variation of Mediterranean mooring, but instead of anchors, lines are run from the bow to bollards or buoys positioned away from the quay. The stern is moored to the quay as in the Mediterranean style. This provides greater stability and control, especially in areas with strong offshore winds.

The choice of mooring method directly influences the number, spacing, and capacity of the bollards needed for the project.

What is the difference between a bollard and a mooring bitt¹⁶?

Using "bollard" and "bitt" interchangeably is common but incorrect. This confusion can cause problems when specifying equipment, as they serve distinct roles in different locations.

A bollard is a single post installed on a dock or quay for mooring a vessel. A mooring bitt, typically a pair of posts on a single base, is installed on the ship's deck for securing mooring lines onboard the vessel itself.

I often clarify this distinction for clients. The easiest way to remember is: bollards are on the shore, and bitts are on the boat. While they look similar and are both used to secure ropes, their design and installation are tailored to their environment. A quay-side bollard is a massive casting anchored deep into the concrete structure of the dock. It's a stationary, passive anchor point. A mooring bitt¹⁶, on the other hand, is part of the ship's structure. It's mounted on the deck and must be engineered to handle the forces transmitted from the bollard through the mooring line, without damaging the ship's deck. Bitts are often called Double Bitts¹⁷ or Twin Horn Bollards and are very common in North America. When someone asks me for a "bollard" for their ship, I know they likely mean a mooring bitt.

Bollard vs. Mooring Bitt

Feature	Mooring Bollard	Mooring Bitt
Location	Quay, Pier, Dock (Shore)	Ship's Deck (Vessel)
Typical Form	Single post (T-head, Pillar)	Paired posts on one base
Function	Shore-side anchor point	Ship-side securing point
Installation	Anchored into concrete/steel	Welded or bolted to ship deck

Understanding this difference is crucial for clear communication and ordering the correct equipment for either the jetty or the vessel.

What is the maximum distance between bollards?

Placing bollards too far apart is a critical design flaw. It creates unsafe line angles and uneven loads, compromising the entire mooring system and putting the vessel at risk.

There is no universal maximum distance; it is determined by the length of the vessels the berth is designed for. A common rule of thumb is to space bollards between 20 to 30 meters apart to ensure effective mooring for a wide range of commercial ships.

I've worked on many quay designs with clients, and bollard spacing¹⁸ is always a key topic. It’s a balance between cost and safety. While there isn't a single magic number that fits all situations, the spacing must allow for proper mooring line angles. Mooring lines are most effective when they are not too steep horizontally or vertically. If bollards are too far apart, the lines become too parallel to the ship, reducing their ability to prevent forward and backward movement. For a general cargo berth, a spacing of 25 meters is a very common and effective starting point. However, for specialized terminals like those for large container ships or LNG carriers, a detailed mooring analysis¹³ is essential. This analysis considers the exact mooring line layout of the design vessels to determine the optimal location for each bollard to ensure loads are distributed safely.

Factors Influencing Bollard Spacing

• Design Vessel Length¹⁹: Longer ships need more mooring points over a greater distance.
• Mooring Line Angles: Spacing must allow for effective angles for spring and breast lines.
• Quay Operations: Spacing must accommodate cranes, vehicle traffic, and other equipment.
• Terminal Type: A ferry terminal has different needs than a bulk cargo terminal.

Ultimately, the goal is to create a mooring pattern that holds the ship securely in all expected conditions without overstressing any single line or bollard.

Conclusion

Choosing the right mooring bollard comes down to understanding its type, size (SWL), and placement. Matching these factors to your vessel and location ensures a safe and cost-effective system.

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