Fender (boating)
The type of fender that is most suitable for an application depends on many variables, including dimensions and displacement of the vessel, maximum allowable stand-off, berthing structure, tidal variations and other berth-specific conditions.
Rope fenders are still used today by historic boat owners and are still offered by a small number of sellers.
Docks and other marine structures, such as canal entrances and bases of bridges, have permanent fenders placed to avoid damage from boats.
Design life of port fenders will vary by ship type, berthing frequency, temperature, saltwater content, and other environmental factors.
Port owner responsibility includes damages by ordinary wear and tear by ships, weathering, faulty mounting, incorrect fender type, etc.
Cylindrical (extruded) fenders are an economical solution to protect most berthing structures and offer ease of installation.
Arch fenders have a better Energy / Reaction force ratio and are recommended for all types of applications.
This advanced feature of the lesser height of fenders improves the material handling capabilities of Deck / Vessel Cranes, which reduces the overall cost of the project.
Maintaining reaction force but doubling energy absorption can be achieved by using two identical cone fenders in a back-to-back arrangement.
It has become an ideal ship protection medium used extensively by large tankers, LPG vessels, ocean platforms, etc.
[5] The submarine hydro-pneumatic fender (SHPF), first developed in the 1980s, is a unique fender system designed to provide minimal hull pressure loads and soft compression during berthing and a large stand-off to accommodate the sizeable bulbous shape of the submarine.
Each SHPF system is customized specially for each type or class of submarine, depending on its water-air ratio, the shape of the hull, berthing-type, energy absorption, and jetty design.
These fenders are typically made of a closed-cell Polyethylene foam core, which is encapsulated in nylon or Kevlar reinforced Polyurethane skin.
Solid rubber fenders have a long history and come in a wide range of anti-collision equipment.
Solid rubber fenders have high energy absorption and reaction force, are low cost, have a long service life, and are easy to install and maintain.
They feature sizeable compressive deformation energy absorption, low reaction force, ability to sail, and easy installation.
[10] Designing a fender system basically is determining what the berthing energy of a vessel or range of vessels will be, then determine what capacity the fender needs to have to absorb that kinetic energy and finally how to find a way to avoid the reaction force creating too much hull pressure.
