Views: 315 Author: NANJING TAIDUN Publish Time: 2026-10-10 Origin: Site
Content Menu
● What Is a Super Arch Rubber Fender?
>> Core Performance Characteristics
>> The Frontal Face: Where the Difference Begins
● Configuration 1: Super Arch Fender WITHOUT PE Pad (Base Configuration)
>> How It Works
>> Advantages
>> When Without-PE-Pad Makes Sense
● Configuration 2: Super Arch Fender WITH PE Pad (Enhanced Configuration)
>> How It Works
>> The UHMW-PE Advantage: Data-Driven Analysis
>> Performance Improvements Documented in Field Applications
>> The Steel Panel: More Than a PE Carrier
>> Design Considerations for PE-Pad Configuration
● Head-to-Head Comparison: Engineering Decision Matrix
● Expert Insight: The Hidden Cost of "Saving" on PE Pads
>> Field Case: Southeast Asian Container Terminal
● Practical Selection Guide: Which Configuration for Your Berth?
>> Choose WITHOUT PE Pad When:
● Conclusion: Engineering Value Over Initial Price
● Frequently Asked Questions (FAQ)
>> 1. What is the friction coefficient difference between rubber and UHMW-PE?
>> 2. Can PE pads be retrofitted to existing super arch fenders?
>> 3. How often do PE pads need replacement?
>> 4. Does adding a PE pad change the fender's energy absorption or reaction force?
>> 5. What is the recommended PE pad thickness for super arch fenders?
>> 6. What certifications should I request for PE-pad super arch fenders?
Introduction: A Small Component with Outsized Impact
When specifying a super arch rubber fender, one decision carries more weight than most engineers initially realize: whether to include a UHMW-PE pad on the frontal panel.
On the surface, it appears to be a minor accessory choice. In practice, this single component determines friction behavior, shear force distribution, hull pressure characteristics, and ultimately the service life of your entire fender system.
As an OEM manufacturer with over 23 years of experience at NANJING TAIDUN MARINE EQUIPMENT ENGINEERING CO., LTD, we have produced super arch fenders in both configurations—with PE pad and without PE pad—for ports across 80+ countries. This article provides an engineering-grade comparison based on that production and field experience.
Before comparing configurations, let us establish the baseline. The super arch rubber fender (also known as V-type or arch fender) is one of the most widely used rubber fender types in modern port infrastructure.
The super arch design achieves high energy absorption with relatively low reaction force—a critical advantage for ports with structural load limitations.
The frontal working face of a super arch fender contacts the vessel hull directly. In the base configuration (without PE pad), this means rubber-on-steel contact.
The friction coefficient for this interface is approximately 0.6—a value that creates significant challenges during berthing.
The bare rubber face contacts the vessel hull directly. Reaction force is distributed through the arched rubber body.
| Advantage | Explanation |
|---|---|
| Simpler design | No additional steel or PE components |
| Lower initial cost | Fewer parts, simpler manufacturing |
| Direct energy transfer | No intermediate panel losses |
| Compact profile | Requires less space from quay face |
The friction problem is fundamental and cannot be engineered away.
With a friction coefficient of 0.6 between rubber and steel hull, the following consequences are unavoidable:
1. High shear forces at berthing – As vessels move vertically (tidal changes, wave action), the rubber face resists movement, generating shear stress at the fender root
2. Root tearing risk – The base of the fender—where it connects to the mounting plate—becomes the failure point
3. Hull paint damage – Rubber abrasion against vessel coating accelerates paint degradation
4. Limited to low-traffic berths – High-frequency berthing accelerates wear dramatically
> *"The friction coefficient between the rubber working face and the vessel hull (steel plate) is as high as 0.6. During service, this often causes tearing and damage at the fender root—a major deficiency of this product."*
> — Industry technical documentation
- Low berthing frequency berths (less than 100 berthings/year)
- Small vessels with minimal vertical movement
- Temporary installations or short-duration projects
- Structural load is not a concern (the shear forces can be accommodated)
A frontal panel (steel plate) is attached to the fender face, covered with a UHMW-PE (Ultra-High Molecular Weight Polyethylene) pad. The vessel contacts the low-friction PE surface instead of bare rubber.
The frontal steel panel serves multiple functions beyond supporting the PE pad:
1. Load distribution – Spreads reaction force across a larger area, reducing hull pressure
2. Structural protection – Prevents direct rubber damage from vessel protrusions
3. PE pad mounting – Provides a flat, durable surface for pad attachment
4. Replaceable wear surface – PE pads can be replaced without replacing the entire fender
> *"The frontal panel is equipped with a frontal frame and PE frontal pad, reducing face pressure and the friction coefficient with the vessel hull, thereby greatly easing shear force during berthing."*
> — Product technical specification
Hull pressure calculation becomes critical when adding a panel:
P = ΣR ÷ (A₁ × B₁) ≤ Py
Where allowable hull pressure varies by vessel type:
| Vessel Type | Allowable Hull Pressure (kN/m²) |
|---|---|
| Gas carriers (LNG/LPG) | 100–200 |
| Bulk carriers | 150–250 |
| Oil tankers | 250–350 |
| Container ships | 400–500 |
The PE pad configuration allows designers to control hull pressure more precisely by selecting appropriate panel dimensions.
From our production data across 80+ countries, a clear pattern emerges.
When a vessel moves vertically against a bare rubber fender face, the high friction generates tensile stress at the fender base. Over time, this creates micro-cracks that propagate through the rubber body.
The failure timeline (typical, without PE pad):
- Year 1–2: No visible issue
- Year 3–4: Surface cracking at root
- Year 5–7: Crack propagation, fender weakening
- Year 7–10: Root failure, fender replacement required
With PE pad:
- Year 1–5: PE pad wears gradually (replaceable)
- Year 5–10: Fender body remains intact
- Year 10–20+: Fender continues in service
The economic reality: The initial cost savings of a without-PE-pad fender are typically recovered within 3–5 years through avoided maintenance and replacement costs.
A terminal operator initially installed super arch fenders without PE pads on a high-traffic berth. Within 4 years, over 60% of fenders showed significant root cracking. Replacement cost plus berth downtime exceeded $180,000.
The terminal subsequently switched to PE-pad configuration. After 7 years of operation, PE pads have been replaced twice (planned maintenance), but no fender body replacements have been required.
- Berthing frequency is low (<100 operations/year)
- Tidal range is minimal (<1m)
- Vessels are small with minimal vertical hull movement
- Initial budget is the primary constraint and life-cycle cost is secondary
- Berthing frequency is moderate to high (>200 operations/year)
- Tidal range exceeds 2m (vertical movement causes shear)
- Vessels include large ships (container, bulk, tanker)
- Hull paint protection is a priority
- Life-cycle cost is the decision driver
- Terminal operations cannot tolerate unplanned downtime
The comparison between super arch rubber fender with PE pad and without PE pad is not a question of "which is better." It is a question of matching configuration to application.
For low-traffic, small-vessel berths, the without-PE-pad configuration offers simplicity and lower initial cost.
For any application where vessel movement generates shear forces—which includes most tidal ports, high-traffic terminals, and large-vessel berths—the PE-pad configuration is the engineering-correct choice. The friction reduction, hull pressure distribution, and root protection it provides translate directly into longer service life, lower maintenance cost, and improved operational reliability.
At NANJING TAIDUN, we manufacture both configurations to international standards (PIANC, ISO, ASTM, EU), with third-party certification available from CCS, BV, LR, TUV, SGS, INTERTEK, and GL.
Need expert guidance on fender configuration for your specific berth conditions?
Contact NANJING TAIDUN MARINE EQUIPMENT ENGINEERING CO., LTD:
- Email: service@taidunmarine.com
- Website: www.taidunmarine.com
- Services: OEM/ODM manufacturing, custom rubber compounding, third-party testing coordination, technical consultation
1. NANJING TAIDUN MARINE EQUIPMENT. "Closed Fender Steel Panel Vs Open Fender Steel Panel: A Complete Engineering Comparison for Port Infrastructure." [https://www.taidunmarine.com/closed-fender-steel-panel-vs-open-fender-steel-panel-a-complete-engineering-comparison-for-port-infrastructure.html]
2. Google Patents. "Composite fender." WO2002022964A1. [https://patents.google.com/patent/WO2002022964A1/en]
Bare rubber against steel hull has a friction coefficient of approximately 0.6. UHMW-PE against steel is 0.15–0.2. This represents a ~70% reduction in friction force, directly translating to lower shear stress at the fender root.
In most cases, yes—if the fender design includes mounting provisions for a frontal panel. However, retrofitting requires engineering evaluation to ensure the fender mounting and anchor bolts can accommodate the additional panel weight and resulting load distribution changes. Consult with the original fender manufacturer or a qualified marine engineer.
PE pad service life depends on berthing frequency, vessel hull condition, and contact pressure. In typical container terminal applications, PE pads last 3–7 years before replacement. In lower-traffic berths, service life can exceed 10 years. PE pads are designed as replaceable wear components—replacing a pad costs significantly less than replacing the entire fender.
The PE pad itself does not significantly change the fender's energy absorption (which is determined by the rubber body compression). However, the steel panel distributes reaction force over a larger area, reducing hull pressure. The fender's reaction force curve remains essentially unchanged, but the point of force application shifts from direct rubber contact to the panel surface.
Typical UHMW-PE pad thickness for super arch fenders ranges from 15mm to 30mm, depending on:
- Vessel size and displacement
- Berthing frequency
- Hull surface condition
Thicker pads provide longer service life but add weight and cost. A 20mm pad is a common specification for medium to large vessel applications.
Request the following documentation:
- Product certificate of conformity (factory-issued)
- Rubber compound material certificate
- Compression test report (energy absorption, reaction force)
- Steel panel coating thickness measurements
- PE pad material certificate (UHMW-PE grade verification)
- Third-party inspection report (CCS, BV, LR, TUV, SGS, INTERTEK, GL as applicable)
