“Pneumatic type fenders”, also known as “pneumatic fenders” or “Yokohama fenders”, are a type of marine fender used to protect ships, docks, and other marine structures during berthing and mooring operations. These fenders are inflatable and filled with air, which makes them flexible and highly effective at absorbing the energy from impacts. Pneumatic fenders are widely used in ship-to-ship transfers, ship-to-dock operations, and in situations where temporary fendering is required.
Key Features of Pneumatic Fenders:
- Inflatable Air Chamber: Pneumatic fenders have a hollow interior that is filled with air. When a vessel makes contact with the fender, the air inside is compressed, absorbing the impact energy.
- High Energy Absorption: Due to the compressibility of air, pneumatic fenders can absorb large amounts of energy while exerting relatively low reaction forces on the vessel or dock.
- Flexibility: These fenders can be deflated and easily transported, stored, or deployed, making them ideal for temporary or emergency use.
- Durable Outer Layer: The outer layer is typically made from thick, wear-resistant rubber, which is resistant to weathering, saltwater, and UV radiation, providing long-lasting protection even in harsh marine environments.
Structure of Pneumatic Fenders:
Pneumatic fenders are made of multiple layers to ensure durability and effectiveness:
- Outer Rubber Layer: Protects the fender from abrasion, aging, and environmental factors.
- Synthetic Cord Layer: Reinforces the fender, providing strength and preventing it from over-expanding.
- **Inner Rubber Layer: Holds the air inside the fender and ensures airtightness.
Pneumatic fenders are often equipped with **tire nets** or **chain nets** for added protection, especially in rough berthing environments. These nets provide an additional layer of protection against punctures or damage from vessel impacts.
Types of Pneumatic Fenders:
- Chain and Tire Net Pneumatic Fenders: These fenders are covered with a network of chains and old tires to protect the fender body from external damage, making them more suitable for rough and high-contact environments.
- Sling Type Pneumatic Fenders: These are simpler versions without the tire and chain nets. They are lighter and easier to deploy but offer less protection in highly abrasive conditions.
- Foam-Filled Pneumatic Fenders: These are similar in design to air-filled pneumatic fenders but instead of air, they are filled with foam. They are non-deflatable and have a high level of energy absorption.
Applications of Pneumatic Fenders:
- Ship-to-Ship (STS) Transfers: Pneumatic fenders are commonly used when two ships berth alongside each other for cargo transfers, especially oil tankers, gas carriers, and bulk carriers. They provide a safe buffer that absorbs energy from both vessels.
- Ship-to-Dock (STD) Operations: They are also widely used in ship-to-dock operations to protect both the dock and vessel from impact during berthing, especially in commercial harbors and industrial ports.
- Temporary Berthing: Because of their mobility and ease of deployment, pneumatic fenders are ideal for temporary berthing, such as in emergency situations or when additional fenders are needed for large vessels.
- Offshore Platforms: They are also used in offshore applications, including oil rigs and floating production storage and offloading (FPSO) units, where vessels frequently berth for loading and offloading cargo.
Advantages of Pneumatic Fenders:
- Superior Energy Absorption: Pneumatic fenders can absorb high impact energy while exerting low reaction forces on the vessel and dock, minimizing the risk of damage to both.
- Low Reaction Force: The air-filled design ensures that the fender deforms gradually under load, reducing the reaction force on vessels during impact.
- Mobility: They are lightweight and easy to deploy or move, making them highly versatile and suitable for temporary installations.
- Durability: Made with high-quality rubber and reinforced with layers of synthetic cord, pneumatic fenders are highly durable and can withstand the harshest marine environments.
- Customizable: They come in a variety of sizes and can be inflated to different pressure levels, making them adaptable for use with various vessel sizes and berthing conditions.
- Floating Capability: Pneumatic fenders naturally float on water, maintaining proper positioning between the vessel and dock, even in tidal conditions or rough seas.
