Floating Foam Filled Fender Configuration

Foam Filled Fenders shall have cylindrical mid-bodies with conical or hemispherical shaped ends terminating in an end fitting on the cylinder’s center line at each end. The diameter of the mid-body shall be as per design.

If conical ends are provided, they shall have an angle of 60 to 75 degrees, when measured from the central axis of the fender. The fittings at either end shall be connected through a central bore of the fender by a central chain, and shall terminate in a swivel fitting which allows the end fitting to rotate freely on the axis of the fender.

The length of the fender from eye to eye of the end fittings shall be as per requested length. End fitting shall be sized so as not to contact loading surfaces when the fender is compressed to 30 percent of its original diameter (70 percent compression).

Dimensional Tolerance: ± 5% for diameter and length.

Foam Core

foam core

The energy absorbing foam core shall be of heat laminated construction using a resilient closed-cell, cross-linked polyethylene foam or EVA foam with the following properties. Use of chipped or granulated particulate foam is not acceptable. Use of adhesive to bond the foam together is not acceptable. The tests shown below all form a part of ASTM D-3575.

Standard Capacity:

Density Range: 55 kg/m3 to 68 kg/m3

Tensile Strength: 293 kPa minimum

Elongation (Ultimate) : 95 % minimum

Tear Resistance: 2.2 kN/m minimum

Compressive Strength (50%): 110 kPa minimum

Compressive Set (Suffix B) : 17.2% maximum

Low Reaction:

Density Range: 29 kg/m3 to 35 kg/m3

Tensile Strength: 200 kPa minimum

Elongation (Ultimate) : 79 % minimum

Tear Resistance:1.5 kN/m minimum

Compressive Strength (50%) : 80 kPa minimum

Compressive Set (Suffix B) : 27% maximum

High Capacity:

Density Range : 79 kg/m3 to 97 kg/m3

Tensile Strength: 546 kPa minimum

Elongation (Ultimate) : 101 % minimum

Tear Resistance: : 4.2 kN/m minimum

Compressive Strength (50%): 168 kPa minimum

Compressive Set (Suffix B): 15.3% maximum

Extra-High Capacity:

Density Range : 115 kg/m3 to 141 kg/m3

Tensile Strength: 738 kPa minimum

Elongation (Ultimate) 120 % minimum

Tear Resistance: 6.5 kN/m minimum

Compressive Strength (50%): 226 kPa minimum

Compressive Set (Suffix B) : 11.5% maximum

Super-High Capacity:

Density Range: 158 kg/m3 to 194 kg/m3

Tensile Strength: 1207 kPa minimum

Elongation (Ultimate) : 120 % minimum

Tear Resistance: 8.8 kN/m minimum

Compressive Strength (50%): 490 kPa minimum

Compressive Set (Suffix B) : 13.5% maximum

Water Absorption: shall be less than 0.34 kg/m2 of cut surface

Working Temperature: -50 degrees C to 40 degrees C

Fender Skin

The outer skin of foam filled fender shall be constructed of elastomer with filament reinforcing as specified. Separate filament reinforcing wraps shall be applied as specified under Filament Wrap. The filament wraps shall be evenly distributed in the inner 75 % to 90 % of the coating thickness.

The outer 10 % to 25 % of elastomer shall have no filament reinforcement. The elastomer and filaments shall be applied in a continuous manner to assure adhesion between the various layers.

The skin shall be of adequate thickness to provide sufficient wraps of nylon to transfer lateral or vertical shear forces associated with vessel berthing and the fender rated reaction force. Calculations shall be provided showing adequate skin thickness assuming a vessel coefficient of friction equal to 0.6.

Dimensional Tolerance: -10% for skin thickness.


The elastomer used in the fender skin shall be non-marking and solvent free. It shall be the reaction product solely of toluene diisocyanate, polyether polyol, and an aromatic diamine. The elastomer shall meet the unreinforced properties:

i. Shore A, Hardness: ASTM D2240, 75 minimum.

i. Tensile Strength: ASTM D412, 13.8 Mpa, minimum.

ii. Elongation (Ultimate): ASTM D412, 300 percent, minimum.

iii. Tear Strength: ASTM D470, 32.4 kN/m, minimum.

iv. Flex Life (Ross): ASTM D1052, 250,000 cycles, minimum.

v. Abrasion Resistance (NBS): ASTM D1630, 100 minimum.

Colour: Colour shall be grey throughout the skin thickness.

Filament Wrap

filament wrap

Construct each filament-reinforcing wrap of continuous filaments applied in a helical pattern, at a helix angle of 45 to 60 degrees to the longitudinal axis of the buoy. A wrap shall consist of two such filament helixes of equal but opposing helix angles.

The spacing between the filaments in the same helix shall be no more than 3.2 mm, measured in a direction parallel to the longitudinal axis of the fender. Each wrap shall extend along the entire longitudinal axis of the fender and shall also encase the fender end fittings and secure them to the fender body.

Filament Reinforcing

The reinforcing filaments in the outer skin shall be nylon tire cord of 2520 denier weight with the following properties:

  1. Breaking Strength: 231 N.
  2. Elongation (Ultimate): ASTM D412, 16 percent.

Reinforced Skin

The reinforced skin, when constructed in accordance with this specification, shall exhibit the following properties when tested in accordance with the guidelines below:

  1. Tensile Strength: When a full-thickness specimen is tested in tension, with the direction of pull aligned with the filament direction (in one helix direction), the specimen shall have the following breaking strength: 31.0 Mpa minimum.
  2. Elongation (Ultimate): In the test for Tensile Strength, the specimen shall have the following elongation at break: 16% minimum.
  3. Tear Strength: When a full-thickness specimen is tested in tear, with the specimen shaped like Die C in ASTM D-624, and with the direction of pull aligned with the filament direction (in one helix direction), the specimen shall have the following tear strength: 78.8 kN/m).


The end fittings of the fender shall be steel and galvanized per ASTM A- 123. The end fittings and internal connecting chain shall be designed and sized to transmit the safe working load and accept the shackle size specified.

Fender End Fittings

The fender shall employ a fitting at each end of the fender body located on the central axis of the fender inside the foam core of the fender. The fitting shall include a central steel weldment made from tubular steel in accordance with ASTM A513 or A53, located on the central axis of the fender, and a truncated cone-shaped annular seat integral with the central member.

The cone-shaped annular seat of each fitting shall cooperate with the axially adjacent conical shaped end of the fender to extend the conical shape of that end to the central member.

The end fittings shall include an integrated freely rotating swivel pad eye designed and sized to transmit the safe working load and shackle size specified. The swivel pad eye shall be held in place by a bolted flange end plate. Both the swivel and end plate shall be fabricated from cast ductile iron in accordance with ASTM A536, Grade 65-45-12. Flange attachment bolts shall be AISI 316 stainless steel.

The elastomeric fender skin shall integrally encase the foam core and the central tubular member and truncated cone-shaped annular seat of each end fitting. The fibers of the filament reinforcing wrap shall also integrally encircle the foam core and the annular seat of each end fitting.

The end fittings at the ends of the fender shall connect to the central chain passing through the center of the fender and the tubular central members so that loads are transferred from the mooring chains to the attachment elements through the central chain.

The connection between the end fittings and the central chain shall allow for tensioning or adjustment of the tension in the central chain.

Floating Foam Fender Performance

The fender shall be designed so that when compressed across its diameter by two parallel flat plates extending the full length and width of the fender, the fender shall absorb the specified energy (- 10 %) with acorresponding specified force (+ 10 %).

This energy absorption performance shall be achieved prior to the point at which the deflection of the fender exceeds 60 % of its initial diameter. Performance shall be based on the nominal characteristics, catalogue data, and measurement units.

Floating Foam Fender Quality

The manufacturer shall have ABS Type Approval on record for the fender type specified. The manufacturer shall have in place a quality management system that complies with ISO 9001.

The manufacturerquality assurance program must ensure that the foam filled fenders are manufactured to the above specifications. Manufacturer shall also have in place a comprehensive environmental management program that complies with ISO 14001.

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