What Is Yokohama Type Fender

Yokohama fender

A Yokohama type fender is a floating pneumatic rubber fender—a cylindrical, air-filled, cord-reinforced marine buffer that absorbs berthing energy between a ship and a dock or between two vessels. The name comes from The Yokohama Rubber Co., which commercialized the design in the 1950s; today “Yokohama type fender,” “Yokohama fender,” and “pneumatic rubber fender” are used interchangeably, with performance governed by ISO 17357-1:2014.

Why Is It Called “Yokohama Type” and Not Just “Pneumatic Fender”

Yokohama Rubber pioneered the compressed-air marine fender using tire-cord and rubber-tank technology. Because the brand became the global benchmark, buyers still say “Yokohama type” even when procuring from any ISO-compliant manufacturer.

Key naming logic:

• Yokohama® fender = original branded product
• Yokohama type fender = generic shape/compliance class (pneumatic, floating)
• Pneumatic rubber fender = technical standard term
• Floating pneumatic fender = emphasizes self-buoyancy at the waterline

In a purchase spec, “Yokohama type” alone is not enough—always state ISO 17357-1:2014, P50 or P80, diameter × length, and net/sling type.

How a Yokohama Type Fender Works

It uses an air-spring principle, not solid-rubber compression:

1. Vessel approaches → fender floats at waterline, tethered by sling or chain pendant
2. Hull contact → reinforced rubber body compresses
3. Internal air pressure rises uniformly (no local buckling)
4. Kinetic energy converts to air compression + elastic cord-layer strain (up to ~70% absorbed)
5. Reaction force stays low → protects hull and quay
6. Vessel backs off → air re-expands, fender recovers shape

At the ISO test point of 60% deflection, makers publish GEA (Guaranteed Energy Absorption) and R (reaction force). A 2500 × 5500 mm P50 fender gives ~943 kJ GEA at ~2019 kN reaction.

Internal Structure (ISO 17357-1 Four Layers)

The body is vulcanized seamless; chains or slings attach to flanges, never the rubber skin.

Yokohama fenders

Types of Yokohama Type Fenders

Net Type (ISO Type I – Chain & Tire Net)

Chain/wire net with used tires or rubber sleeves around the body.

• Use: VLCC/LNG STS, permanent berths, rough seas
• Pros: Longest abrasion life, hardest impact tolerance
• Size range: Ø500 mm – Ø4500 mm

Sling Type (ISO Type II – No Net)

Thick outer rubber + integral lifting slings.

• Use: Yachts, naval, cruise, calm-water temporary berthing
• Pros: Lightweight, non-marking options, fast deploy
• Size range: Ø500 mm – Ø3300 mm[ccitation:2]

Hydro-Pneumatic Fender

Part air, part water ballast, held vertically submerged.

• Use: Submarines, low-freeboard hull contact, naval sub-surface ops
• Always custom-engineered

P50 vs P80 (Initial Pressure Class)

Never inflate a P50-rated body to 80 kPa—cord angle and end-ring safety factor differ.

Yokohama Type vs Foam vs Solid Fender

• Yokohama / pneumatic: air spring, floating, low reaction, deflatable for shipping
• Foam-filled: closed-cell foam, floating, no pressure upkeep, heavier
• Solid rubber (cell/cone): fixed to quay, no tidal tracking, higher hull pressure

Pneumatic wins for STS, tidal STD, and sensitive hulls.

Yokohama type fenders

Where Yokohama Type Fenders Are Used

• Ship-to-ship (STS) crude/LNG/product transfers
• Ship-to-dock (STD) tidal wharves and marginal berths
• FPSO / FSU offloading
• SPM and CBM buoy mooring
• Naval berthing and submarine tendering
• Offshore wind CTV docking
• Emergency lay-by fenders

How to Specify One Correctly

Minimum compliant line item:

Yokohama type pneumatic rubber fender, ISO 17357-1:2014, P50, 3300 × 6500 mm, Type I chain-tire-net, with BV prototype test, safety valve, mill cert.

Verify: GEA/R at 60% deflection, cord specification, relief valve on ≥Ø2500 mm, third-party class report (ABS/BV/DNV/CCS/LR).

Maintenance Basics

• Check pressure monthly (±10% of rated)
• Inspect chain nets/tire wear every 3–6 months
• Wash salt, store shaded, away from ozone/heat
• Keep safety valve functional
• Typical service life: 6–10 years with correct care

FAQ

Is Yokohama type fender the same as pneumatic rubber fender?

Yes. “Yokohama type” is the generic trade-origin name; “pneumatic rubber fender” is the ISO technical name. Both mean a floating, air-filled, cord-reinforced marine fender.

What does P50 mean on a Yokohama fender?

P50 means the initial internal air pressure is 50 kPa at 20 °C per ISO 17357-1:2014. P80 means 80 kPa.

Do all Yokohama fenders float?

Yes—by definition a pneumatic Yokohama type fender is self-floating and tracks tide/swell. Fixed “Air Block” variants exist but are not the floating pneumatic class.

How long does a Yokohama type fender last?

6–10 years typical, depending on pressure discipline, net type, and UV exposure.