How To Do The Pneumatic Fender Performance Testing?
02/02/2026How Many Types of D Type Rubber Fenders Are There?
Introduction
When a tugboat or workboat hits a dock many times every day, the wrong fender can wear out fast — or even fail when protection is needed most. That is why choosing the right D type rubber fenders is very important.
Many buyers see different names from different suppliers and feel confused. But in real marine projects, most D fenders fall into just three main structural types.
These three types are:
- DD Type Rubber Fender
- DO Type Rubber Fender
- Solid D Rubber Fender
The difference mainly comes from the inside structure — whether the core is D-shaped hollow, round hollow, or fully solid.
What Are D Type Rubber Fenders?
D type rubber fenders are simple but strong marine protection products. They are widely used on:
- Tugboats
- Barges
- Fishing vessels
- Small docks and wharves
They are popular because they are easy to install, low cost, and provide good protection against repeated impacts.
The 3 Main Types of D Type Rubber Fenders
1. DD Type Rubber Fender
Structure:
Inside hollow core is D-shaped.
Main Advantages:
- Good energy absorption
- Balanced reaction force
- Flexible structure
Typical Applications:
- Tugboats
- Workboats
- General dock protection
DD type is one of the most commonly used D rubber fenders in marine projects.
2. DO Type Rubber Fender
Structure:
Inside hollow core is round (O-shaped).
Main Advantages:
- Softer compression response
- Better stress distribution
- Good for vessel mounting
Typical Applications:
- Vessel side mounting
- Push barges
- Frequent berthing operations
DO type keeps the same outside D shape but changes the inside bore to round.
3. Solid D Rubber Fender
Structure:
No hollow inside — fully solid rubber.
Main Advantages:
- Highest wear resistance
- Longest service life
- Handles heavy loads
Typical Applications:
- Heavy-duty tugboats
- Mining docks
- High abrasion working areas
Solid D fenders are often used where durability is more important than softness.
Why Most Projects Only Use These Three Types
Some suppliers list extra names, but most of them are small variations of these three core designs.
The main real differences come from:
- Internal bore shape
- Rubber compound
- Installation design
But structurally, most D rubber fenders still belong to DD, DO, or Solid categories.
How to Choose the Right D Rubber Fender
Choose DD Type If You Need
- Balanced performance
- General marine use
- Cost-effective solution
Choose DO Type If You Need
- Softer compression
- Better hull fitting
- Vessel-mounted protection
Choose Solid D Type If You Need
- Maximum durability
- Heavy-duty working conditions
- High friction environments
Conclusion
In most marine and port projects, D type rubber fenders can be divided into three main types:
✔ DD Type Rubber Fender
✔ DO Type Rubber Fender
✔ Solid D Rubber Fender
Understanding these three types helps engineers and buyers choose faster and avoid overpaying for unnecessary designs.
FAQ
What is the most common D rubber fender type?
DD type is usually the most common because it offers balanced performance and good cost efficiency.
Are solid D rubber fenders better than hollow ones?
Not always. Solid fenders last longer but usually have higher reaction force. Hollow types often absorb energy better.
Can D rubber fenders be customized?
Yes. Most manufacturers can customize length, drilling holes, and rubber compound.
Where are D type rubber fenders most commonly used?
They are widely used on tugboats, barges, small docks, and workboat berthing areas.
How long do D rubber fenders usually last?
Depending on usage and rubber quality, they can last many years in normal marine working conditions.