Tugboat Fender Types and Application

1.Introduction: Why Tugboat Fenders Matter

Tugboats play a crucial role in assisting large vessels during berthing, unberthing, and maneuvering operations. These small yet powerful ships exert significant pushing and pulling forces on the hulls of much larger vessels or quay walls. To ensure both safety and efficiency during these demanding operations, reliable tugboat fenders are essential.

Tugboat fenders act as energy-absorbing buffers, protecting both the tug and the assisted vessel from damage caused by impact and friction. Depending on the tug’s operational mode—such as escorting, pushing, or side assistance—different fender types are used. Among the most common and effective designs are W-type, M-type, and D-type rubber fenders.

2.Overview of Tugboat Fender Types

Tugboat fenders differ from port or quay fenders in both structure and installation method. While quay fenders are stationary, tugboat fenders are mounted directly on the tug's bow, stern, or sides, allowing continuous movement and contact during operations.

The most widely used types include:

Fender Type	Typical Shape	Installation Area	Key Features
W-Type Fender	Deep groove with flexible “W” profile	Bow and stern	High energy absorption, ideal for curved surfaces
M-Type Fender	Central leg with side arms (“M” shape)	Bow, stern, sides	High stability, easy mounting, strong hold
D-Type Fender	Semi-circular “D” profile	Sides and corners	Compact design, versatile use, easy replacement

Each type offers unique advantages depending on the vessel’s structure and operating environment.

3. W-Type Tugboat Fender

3.1 Design Features

The W-type fender is one of the most robust and widely used fenders for ocean-going tugs. Its unique “W” cross-section allows the rubber body to wrap around curved hull surfaces, ensuring large contact areas and excellent energy absorption. The grooves between the “legs” enhance flexibility, enabling the fender to deform smoothly under load.

Typical W-type fenders are manufactured from high-quality EPDM or natural rubber, ensuring superior resistance to ozone, seawater, and weathering. The internal hollow structure optimizes the energy-to-reaction ratio, providing maximum protection without excessive stiffness.

3.2 Advantages

(1) High energy absorption capacity

(2) Suitable for escort and ocean towing operations

(3) Strong grip and anti-slip surface pattern

(4) Easy installation with longitudinal through-ropes or chain anchors

(5) Long service life, even under extreme conditions

3.3 Typical Applications

W-type fenders are typically used on:

(1)Offshore escort tugs operating with LNG carriers or oil tankers

(2)Large harbor tugs handling vessels over 100,000 DWT

(3)Bow and stern areas requiring wide, flexible contact surfaces

The W-type’s performance and durability make it ideal for heavy-duty applications where both impact absorption and continuous friction resistance are required.

4. M-Type Tugboat Fender

4.1 Design Features

The M-type fender resembles the W-type but has a central leg and two side arms, forming an “M” profile. The middle leg provides a solid attachment area, allowing the fender to be firmly bolted or chained onto the hull. Its design gives a perfect balance between flexibility and stiffness, ensuring excellent hull conformity.

Unlike the W-type, the M-type has flatter contact faces, which helps distribute reaction forces more evenly. The side grooves improve energy absorption and help the fender maintain stability under heavy compression.

4.2 Advantages

(1) Excellent stability and grip during push-pull operations

(2) Easier installation with pre-drilled holes or mounting plates

(3) Balanced performance for both bow and side protection

(4) Durable rubber compounds with strong abrasion resistance

4.3 Typical Applications

M-type fenders are commonly installed on:

(1)Harbor and coastal tugs performing frequent push-pull operations

(2)Tugboats operating in confined ports or inland waterways

(3)Vessels requiring side protection against barges and quays

Their versatility makes them one of the most cost-effective and widely adopted solutions in tugboat design.

5. D-Type Tugboat Fender

5.1 Design Features

The D-type fender is a traditional yet highly effective solution. With its semi-circular “D” shape and flat mounting base, it is extremely easy to install on both flat and curved surfaces. Available in solid or hollow designs, D-type fenders offer moderate energy absorption and low reaction force, suitable for light- to medium-duty tug operations.

D-type fenders are often extruded in continuous lengths, allowing customized cutting and seamless installation around the hull.

5.2 Advantages

(1) Compact, lightweight, and cost-effective

(2) Simple installation using bolts or adhesive strips

(3) Available in various diameters and hardness grades

(4) Ideal for protecting corners, sides, and sheer strakes

5.3 Typical Applications

D-type fenders are widely used for:

(1)Small and medium harbor tugs

(2)Workboats, pilot boats, and fishing vessels

(3)Dock edges and barge protection

Their simplicity and adaptability make them a popular choice for smaller tugboats and support vessels operating in sheltered environments.

6. Selecting the Right Tugboat Fender

Choosing the correct fender type depends on several factors:

Parameter	Recommended Fender	Notes
Heavy-duty escort operations	W-Type	High energy absorption, flexible surface
Push-pull harbor operations	M-Type	Balanced stiffness and stability
Small or medium tugs	D-Type	Compact, economical, easy to replace
Curved hull design	W-Type / M-Type	Better conformity to shape
Limited space or tight berths	D-Type	Simplified installation and maintenance

Other considerations include fender hardness (Shore A), rubber compound type, environmental exposure, and maintenance frequency.For optimal performance, tug operators should also consider combining fender types—for example, using W-type on the bow and D-type along the sides—to achieve full protection coverage.

7. Maintenance and Replacement Tips

Even the most durable fenders require regular inspection and maintenance to maintain their performance. Key recommendations include:

(1) Check for cracks, cuts, or permanent deformation after operations.

(2) Inspect mounting bolts, chains, and backing plates for corrosion.

(3) Replace damaged sections promptly to avoid uneven loading.

(4) Clean surfaces to prevent debris accumulation between fenders and hull.

(5) Use only OEM-quality replacement fenders to maintain energy-absorption characteristics.

Proper care not only extends service life but also reduces long-term operating costs.

8. Conclusion

Tugboat fenders are critical safety components ensuring smooth, damage-free operations between tugs and assisted vessels. Among all types, W-type, M-type, and D-type fenders represent the most efficient and reliable solutions—each suited to specific working environments and vessel designs.

Selecting the right combination of fenders enhances safety, prolongs service life, and improves overall operational efficiency. JIER Marine is a leading manufacturer and supplier of marine fender systems, offering a complete range of W-type, M-type, D-type, and cylindrical tugboat fenders.From design to installation, JIER Marine provides customized tugboat fender solutions tailored to your operational needs.