The cylindrical rubber fender, with its high elasticity rubber material and cylindrical design, efficiently absorbs the impact force of ships, evenly disperses the impact energy, and significantly extends the service life of port facilities. It is an ideal protection choice for ports with large tidal ranges.
Characteristics and Applications of Cylindrical Rubber Fenders
The cylindrical rubber fender is an important component of port protection facilities, and its unique structural design enables it to effectively absorb impact energy when ships berth.
This type of fender is made of highly elastic rubber material, and its cylindrical appearance allows it to evenly distribute ship impact forces, protecting the dock structure and hull from damage. Cylindrical rubber fenders are suitable for small and medium-sized docks and berths, especially performing well in ports with large tidal ranges.
Its simple structure, economical cost, and convenient installation make it the preferred protection solution for many port projects.
The most prominent feature of cylindrical rubber fenders is their impact resistance.
Rubber materials themselves have excellent resilience and energy absorption capacity. When a ship docks, the fender transforms kinetic energy into elastic potential energy through deformation, which is then slowly released to reduce the impact on the dock and the ship.
This buffering effect greatly reduces the risk of structural damage and extends the service life of port facilities.
When installing cylindrical rubber fenders, tidal changes and water level fluctuations need to be considered.
Fenders are usually fixed at the forefront of the dock with bolts, and their installation height needs to be determined according to the local highest and lowest tide levels to ensure that they can function under various water level conditions.
During the installation process, attention should also be paid to controlling the gap between the fender and the dock structure. If it is too large, it will reduce the protective effect, while if it is too small, it may affect the compression deformation space of the fender.
In terms of maintenance, cylindrical rubber fenders are relatively simple.
Regularly inspect the surface for cracks, wear, or aging.
The rubber material itself is resistant to seawater corrosion, but it will gradually age under long-term ultraviolet irradiation, so surface protection treatment can be carried out if necessary.
Compared to other types of fenders, cylindrical structures do not have complex internal components and have lower maintenance costs.

Pneumatic Fenders is a hollow bag type anti-collision device made of high-strength synthetic rubber and special skeleton materials, which forms a buffering system with specific pressure and elastic modulus by filling compressed air.
Pneumatic fenders are mainly composed of hollow rubber airbags made of high-strength synthetic rubber and special skeleton materials. Its basic structure includes outer layer adhesive, inner layer adhesive, curtain fabric layer (skeleton material), winding ring, end flange, as well as components such as inflation pipe, deflation valve, one-way valve, etc. The outer layer of adhesive protects the skeleton material and the inner layer of adhesive from external damage; The inner layer of adhesive prevents gas leakage and maintains air pressure; The curtain fabric layer serves as the skeleton material to provide structural strength.
Referring to the patent “An Pneumatic Rubber Fender Structure” (CN202320874102.0), its structure also includes a buffering anti-collision mechanism and a sealing mechanism. The buffer anti-collision mechanism (such as fixed blocks, connecting ropes, and anti-collision tires) cooperates with the inner sealing plate to enhance the buffering and shock absorption effect; Sealing mechanisms, such as flanges and hemispherical sealing shells, can prevent components such as inflation pipes, deflation valves, and check valves from being corroded by water mist, thereby improving their service life.
According to the form of external protection, pneumatic rubber fenders can be divided into unsheathed and sheathed types. Sheath type (such as tire chain mesh, rope tire, wire rope tire mesh, etc.) extends the service life of fenders by wrapping a sheath (such as tire rope mesh) outside the bladder.

Its main features include:
1. The absorption of impact energy is relatively large, and the anti impact force on the ship is relatively small.
2. The installation is relatively simple.
3. It has good elasticity and is less likely to undergo permanent deformation under compression.
4. Lightweight. This type of fender has been applied in scenarios such as oil tankers, container ships, yachts, offshore platforms, large shipyards, docks, and bridge piers.
5. The performance is relatively stable under inclined compression conditions.
Some products are made using integral winding technology, with no seams and uniform force distribution at all points. Their overall performance is better than traditional overlapping fenders.
This type of product needs to pass relevant quality system certification and classification society inspection.

I. Scope of Application and Definition

This specification applies to all operations involving the lifting and gradual launching of ships from above their self-supporting structures using an marine airbag system in shipyards, shipbuilding yards, and related dock areas. The marine airbag system typically consists of multiple marine airbag units, an air supply system, a control valve assembly, pressure gauges and pipelines, support and positioning components, as well as cushioning parts that come into contact with the ship’s hull. The launching operation involves various factors such as mechanical loads, hydrodynamics, and environmental impacts, and must be conducted under the premise of ensuring the safety of the ship’s structure, the personal safety of the operating personnel, and the protection of the surrounding environment.

II. Basic Principles and Safety Requirements

With safety as the premise, we adhere to the principle of “who organizes, who is responsible, who operates”, clarifying the responsibilities and authorities of personnel at all levels.
Conduct a risk assessment before the operation, list key risk points and corresponding countermeasures; assign dedicated safety personnel on site to oversee the implementation.
The ship launching airbag and pipeline system should comply with the design parameters, and any modifications must be approved by the design unit or manufacturer and documented in writing.
The operation site should be equipped with necessary risk elimination and emergency evacuation routes, maintain smooth communication, and set up emergency assembly points and rescue equipment when necessary.
The processes of marine ship launching airbag inflation and deflation, hull lifting, and launching need to be controlled synchronously to avoid single-point overload, eccentric loading, or asymmetric stress.
Prioritize environmental protection, prevent incidents such as seawater pollution and gas source leakage, and ensure that all actions are carried out within permissible waters and weather conditions.

III. Organization and Responsibilities Project Supervisor

Fully responsible for the planning, resource allocation, risk control, and final acceptance of the water balloon operation.
Operation team leader (on-site person in charge): coordinate on-site, execute according to procedures, and ensure smooth connection between each link.
Air source and valve control personnel: responsible for connecting the air source system, setting pressure, operating valves, and monitoring safety.
Safety supervisor: Inspect the site, check the completeness of personal protective equipment, area signage, protective facilities, and emergency equipment, and promptly correct any violations.
Command signaler: Pass instructions between the equipment control console and the hull, ensuring accurate and error-free transmission of information.
Observation and recording personnel: Record key data such as the hull’s attitude, marine airbag status, load, and displacement for evaluation and tracking purposes.

IV. Site Preparation and Materials

The site should have a clean working area, a level base, stable lifting points, and necessary anti-slip and anti-collision measures.
The airbag unit, connecting pipeline, pressure relief and exhaust equipment, pressure gauge, valve assembly, control panel, limiting device, damping and buffer components, etc., should be intact and fully inventoried, and should match the ship’s type and weight.
Safety protective equipment, including helmets, safety shoes, gloves, goggles, etc., should be fully equipped. Emergency rescue tools and firefighting equipment should be readily available and functional on site.
The weather and sea conditions must meet the launching requirements, with factors such as wind, waves, visibility, and temperature falling within acceptable ranges; if these conditions are not met, the operation should be postponed.

Cylindrical rubber fenders perform better during longitudinal and crosswise motion when ship berthing. Cylindrical marine rubber fenders are one rubber marine fenders in hollow cylindrical shape, they can be used together with arch rubber fenders, or d type rubber fenders. Cylindrical rubber fender are easier to be installed, either horizontally, vertically or diagonally by anchoring chain or steel bar to connect mooring chains, then hung on wharfs or ports. Marine rubber cylindrical fender are suitable for both large and small vessels, available in any diameter and length to combine a wide range of sizes for different applications.

Features of cylindrical rubber fenders

1. Higher energy absorption with reasonable lower reaction force and surface pressure
2. PIANC tested and certified
3. Strong adaptability transverse and vertical shape while ship berth
4. Particularly suitable for renovation of old wharfs
5. Widely applied for smaller ships and bigger barges
6. Easier to be installed and maintained
7. Reasonable cost with less hull presure
8. Long life span, endurable structure
9. Tolerant larger compression

Installation of cylindrical rubber fenders

Chain bearing & Steel bar bearing

Performance and dimension of cylindrical marine rubber fenders

welcome to visit:
Super Cone Rubber Fenders, Super Cell Rubber Fenders, D Type Marine Rubber Fenders, Super Arch Rubber Fenders

As well as foam filled marine fenders

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“General surface support buoys mainly have three types which are pick-up buoys, chain-through buoys and cylindrical buoys”

Construction of General Surface Support Buoys

Ronsen general surface support buoys are manufactured with high quality closed-cell PE/EVA resilient foam core, encapsulated with self-coloured polyurethane elastomer skin.

A. Laminated closed cell resilient foam core, unsinkable design

Cylindrical support buoys are made with highest quality closed-cell PE/EVA foam. This resilient foam make the buoys self fendering with high impact absorption capacity. Even the skin was punctured, it also is unsinkable without absorbing water. With our unique laminating process, each foam core is integrity. The foam core cannot be ruptured after long time service.

B. Tough nylon filament reinforced polyurethane skin

Cylindrical Buoy’s  skin is constructed of polyurethane elastomer which is reinforced with nylon filament. The polyurethane skin is unique elastomer specifically for offshore applications. It is high resistance to abrasion, fatigue and ultra violet degradation and is significantly more durable.

C. Steel work and end assembly

Through central tube with longitudinal gussets and extend load distribution flanges at each end, epoxy coated or hot-dpped galvanized, are encased in a closed-cell urethane foam central body. Optional bail eye, clevis eye, swivel, chain locking plate, single locking pin end fitting are available.

Specification

Cylindrical Buoys (RS-CB)

Chain Through Buoys (RS-CTB)

Pick Up Buoys (RS-PUB)

A support chain through cylindrical mooring buoy is a device that floats on the surface of the water, typically used to mark marine areas or indicate certain maritime activities. The following is a detailed introduction about surface support buoys:

1、 Definition and purpose

A support cylindrical chain through buoy is a platform that floats on the sea surface and is equipped with various sensors and instruments for monitoring and studying the marine environment. They are important tools for marine scientific research and marine resource management, widely used in various fields such as marine scientific research, marine resource development, and marine environmental protection.

2、 Type and Function

According to their different purposes and shapes, surface support buoys can be divided into various types, including navigation buoys, fishery buoys, marine science buoys, meteorological buoys, etc.

Navigation buoy: used to mark navigation channels and dangerous areas, helping ships avoid obstacles and dangerous areas. Common navigation buoys include lighthouses, lightboats, floating lighthouses, and floating beacons.

Fishery buoy: a device used to mark fishing activities, indicate the location of fishing nets and gear, help fishermen find their fishing equipment more easily, and protect other vessels from entering the fishing area.

Marine science buoy: used to monitor the marine environment and climate change, measure ocean parameters such as water temperature, salinity, and ocean currents, provide important information about the marine environment, and help scientists better understand the ocean and climate change.

Meteorological buoy: used to monitor meteorological conditions, measure wind speed, direction, and wave height at sea, providing important data for meteorological prediction and monitoring.

Classified by main body shape: The main body shapes of offshore buoys include disc-shaped, cylindrical, spherical, ship shaped, etc. The disc-shaped buoy is suitable for various sea areas due to its unique shape and is widely used; support mooring buoys have a deep draft and are used for submerged ocean profiling observations; Spherical buoys have good wave following properties and are used for observing surface wave parameters; The boat shaped buoy has a shallow draft and is suitable for observing the wind field profile of inland rivers or nearshore waters.

Classified by anchor system: divided into anchor system and drifting buoy. Anchored buoys can limit displacement range, improve survival performance, and serve as fixed and recovery monitoring tasks; Drifting buoys are used for mobile or abandoned monitoring tasks with variable monitoring range or low recovery value.

Classified by observation function: there are universal and specialized types. Universal buoy electronic equipment has high integration, comprehensive observation parameters, and can observe multi surface data such as wave height and wave period; Specialized buoys have strong targeting for sea conditions, single observation parameters, and can detect data in extreme environments.

Classified by diameter size: usually divided into large, medium, and small buoys, with specific ranges of over 10m, 3-10m, and less than 3m. Generally, the larger the size of the buoy, the stronger its survivability.

In addition, there are some special types of buoys, such as nuclear radiation buoys, specifically used to monitor the radioactive levels in the waters near nuclear facilities.

3、 Working principle

Surface support mooring cylindrical chain through buoys collect real-time marine environmental data by carrying various sensors and instruments, and transmit the data back to ground measurement and control terminals or data centers through wireless communication. These data can be used in various fields such as marine science research, meteorological forecasting, and resource management.

4、 Application examples

Marine science research: Scientists can use data collected by marine science buoys to study changes in marine ecosystems, ocean circulation, marine pollution, and other issues.

Meteorological prediction: The data provided by meteorological buoys can help meteorological departments more accurately predict weather phenomena such as weather and storms, improving the accuracy and reliability of meteorological forecasts.

Resource management: Ocean buoys can also be used to monitor the distribution and quantity of marine resources, providing a basis for the rational development and utilization of marine resources.

In summary, support buoys play an important role in various fields such as marine scientific research, meteorological forecasting, and resource management. With the continuous advancement of technology and the expansion of application fields, sea surface buoys will play a more important role in the future.

EVA polyurethane fenders are made of a new type of polymer material with high elastic modulus, which has high strength, elasticity, adhesion, and maximum impermeability, and can achieve high economic value EVA fender is a kind of foam fender that uses light and highly elastic foam as the buffer medium. It has a better floating fender system than pneumatic fender, and is currently widely used in ports, offshore and ship berthing operations

EVA foam fenders, as an alternative to inflatable fenders for ships, use a new spray coating formula to produce fenders that are not only colorful but also sturdy and durable, with a service life 7-10 times longer than pneumatic rubber fenders This compression type fender uses polyurea material as the outer protective layer and EVA foam material or plastic foam as the cushioning medium inside; During use, it absorbs the impact energy of ships through its compression deformation, thereby reducing the damage to the dock and ships

The main application characteristics of EVA polyurethane fenders are:

Since it uses highly elastic foam as the medium, it has good floating performance and will not be affected by the tide Flexible to use and made of foam material, it is lightweight and easy to install and disassemble It has the characteristics of high energy absorption and low reaction force. Due to its solid nature, compared with inflatable rubber fenders, it has the advantages of not being afraid of friction, not afraid of puncture, not requiring inflation, and long service life By using spray coating formula, we can provide multiple colors according to customer selection, which are beautiful and practical Our company produces EVA polyurethane foam fenders, which come in different sizes and can be provided according to customer needs. Currently, EVA solid fenders are widely used in practical operations on docks, ships, and yachts.

Inflatable floating pneumatic yokohama marine rubber fender – Popular updated fender products in the international shipping industry today
The inflatable ship rubber fender, also known as the inflatable rubber bumper, is a hollow bladder-type anti-collision device made from high-strength synthetic rubber and special skeleton materials. It uses compressed air as the cushioning medium to absorb ship impact energy, achieving collision prevention.
Inflated floating yokohama ship rubber fenders possess comprehensive performance characteristics such as low reaction force, high energy absorption efficiency, and fatigue resistance durability. Their features include significant impact energy absorption, minimal reverse force on vessels, simple installation, excellent elasticity, and lightweight. The products are primarily categorized into types like 50kPa and 80kPa based on inflation pressure, and are widely used in various scenarios such as ships, offshore platforms, port terminals, and bridge piers.

Definition and Working Principle

Inflatable rubber fender is a hollow bag type anti-collision device made of high-strength synthetic rubber and special skeleton materials, which forms a buffering system with specific pressure and elastic modulus by filling compressed air.
Its working principle is based on the synergistic effect of gas compressibility and rubber deformation characteristics, which can effectively absorb the kinetic energy of ship collisions through its own deformation, and evenly distribute the impact load. At the same time, it has comprehensive performance such as low reaction force, high energy absorption efficiency, and anti fatigue durability. According to the type, fenders can be divided into two types: 50kPa (0.05MPa) and 80kPa (0.08MPa)

Structure and Material

Inflatable rubber fenders are mainly composed of hollow rubber airbags made of high-strength synthetic rubber and special skeleton materials. Its basic structure includes outer layer adhesive, inner layer adhesive, curtain fabric layer (skeleton material), winding ring, end flange, as well as components such as inflation pipe, deflation valve, one-way valve, etc. The outer layer of adhesive protects the skeleton material and the inner layer of adhesive from external damage; The inner layer of adhesive prevents gas leakage and maintains air pressure; The curtain fabric layer serves as the skeleton material to provide structural strength.
Referring to the patent “An Inflatable Rubber Fender Structure” (CN202320874102.0), its structure also includes a buffering anti-collision mechanism and a sealing mechanism. The buffer anti-collision mechanism (such as fixed blocks, connecting ropes, and anti-collision tires) cooperates with the inner sealing plate to enhance the buffering and shock absorption effect; Sealing mechanisms, such as flanges and hemispherical sealing shells, can prevent components such as inflation pipes, deflation valves, and check valves from being corroded by water mist, thereby improving their service life.
According to the form of external protection, fenders can be divided into unsheathed and sheathed types. Sheath type (such as tire chain mesh, rope tire, wire rope tire mesh, etc.) extends the service life of the fender by wrapping the sheath (such as tire rope mesh) outside the bag

Generally speaking, the standard pressure range for marine airbags is roughly between 0.1MPa and 0.5MPa, but the specific value needs to be determined based on the actual application scenario and the manufacturer’s technical specifications. Marine airbag is an auxiliary equipment that uses high-pressure gas to generate elastic deformation to carry and move ships, and is widely used in ship launching, shifting, maintenance and other operations.

The technical principle is mainly based on the compressibility and elasticity of gases. By injecting a certain pressure of gas, the airbag expands, providing sufficient buoyancy or support force. In terms of application scenarios, the selection of standard pressure for marine airbags needs to consider factors such as the tonnage of the vessel, the size and quantity of airbags, and the operating environment. For example, for small vessels or light operations, the standard pressure of airbags may be relatively low to meet the requirements of economy and safety; For large vessels or heavy operations, it is necessary to choose airbags with higher standard pressure to ensure sufficient load-bearing capacity and stability. In terms of industry standards, the production and use of marine airbags must comply with relevant international and domestic standards, such as ISO, GB, etc. These standards provide clear regulations on the materials, manufacturing processes, performance parameters, and testing methods of airbags to ensure their quality and safety. For example, the standard may specify key indicators such as deformation, compressive strength, and service life of airbags under specific pressures, providing important basis for the design and selection of airbags.

In addition, the standard pressure of marine airbags is also affected by manufacturing processes and material properties. Advanced manufacturing processes and high-quality materials can improve the pressure resistance and sealing performance of airbags, allowing for the use of higher standard pressures. Therefore, when choosing marine airbags, in addition to considering their standard pressure, attention should also be paid to their manufacturing process and material quality. When using marine airbags, it is necessary to strictly follow the technical specifications and operating instructions provided by the manufacturer to ensure the safety and effectiveness of the airbags. Especially during the inflation and deflation process, it is necessary to control the rate of pressure change to avoid damage to the airbag due to sudden pressure changes. At the same time, regular inspection and maintenance of airbags are also important measures to ensure their long-term stable operation.