Kinetic Energy: E= ½. M. V2 10/5/2017. A simple and an effective tool. Presented by Rolf Dahlqvist Trelleborg Marine Systems (Sweden)

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1 10/5/2017 A simple and an effective tool Presented by Rolf Dahlqvist Trelleborg Marine ystems (weden) Kinetic Energy: E= ½. M. V2 M = Mass of the object V = Velocity of moving object Increasing trend in vessel size (M) and berthing speed (V) 1

2 Load-Deflection (L-D) curve of a cone fender Energy= Area under the L-D curve Compression speed: 2-8mm/s Difference in load deflection curve between low and high berthing velocities 150mm/s velocity 2-8mm/s velocity 4 2

3 Impact of increased reaction force on the fender system design teel Panel: Contact face to disperse hull pressure and allow sliding Anchors/bolts Chains: Restricting panel movement Mono piles PIANC suggested the use of Velocity Factor What is Velocity Factor (VF)? 150mm/s velocity VF 2-8mm/s velocity VF: ratio of reaction force at berthing speed and testing speed 3

4 Factors impacting the magnitude of VF First factor: compression speed or strain rate Fender CN 300 CN 300 CN 2000 Height 300 mm 300 mm 1200 mm Compression speed 1mm/s 150mm/s 150mm/s train rate ( Compression speed/height) 1/300=.003/s 150/300=0.5/s 150/2000=0.075/s VF (NR+BR) train rate: The higher the strain rate, the higher the gap (magnitude), higher is the VF Factors impacting the magnitude of VF econd factor: compound composition (type & % of rubber, filler, oil) ynthetic rubber has a higher VF factor than natural rubber, which decreases with strain rate 4

5 What is Temperature Factor (TF)? Temperature has a large effect on the reaction force of a fender Reaction force will increase at lower temperatures and decrease at higher temperatures Fenders are typically tested at 23ºC. However, in practice they will operate at different temperatures In order to establish performance at alternative temperatures, temperature factor (TF) must be applied 9 Temperature Factor Compound specific ynthetic rubber has a higher TF than natural rubber (NR) especially at low temperatures 10 5

6 Longevity and rubber composition Two samples were chosen for testing: 20% recycled rubber 75% recycled rubber The Arrhenius relationship Given by the equation: (1) Taking logarithm in both sides of the equation Log K(T) = Log A Where: C: Log A K(T): Reaction rate E: Activation energy R: Gas constant T: Absolute temperature A and C: Constants Log K(T) = C (2) Findings 40ºC 40ºC 30ºC 30ºC 20ºC 20ºC Predicted life cycle Predicted life cycle Rubber compounds with 20% recycled rubber The fender with low recycled rubber has a lifecycle almost 10 times longer at 20 C Rubber compounds with 75% recycled rubber Rubber composition is crucial in determining the longevity of the fender 6

Rubber quality and efficiency of fender Efficient fender Energy : 100

of 900mm 100% Natural Rubber(NR) NR+BR 1 112 Reaction (kips) 200 890

(M019373) Fender 3 (M019372) 50 222 Typical Factory Data from 2008 0 0

composition is the key Performance factors are compound specific They

of fender Rubber composition Performance test results Temperature

7 Rubber quality and efficiency of fender Efficient fender Energy : 100 Reaction : 100 E/R : 1 Less efficient fender Energy : 100 Reaction : 120 E/R : Reaction vs. Percent Deflection Deflection (mm) % of 900mm 100% Natural Rubber(NR) NR+BR Reaction (kips) NR+BR+10% Recycled Rubber Fender 1 (M019761) Fender 2 (M019373) Fender 3 (M019372) Typical Factory Data from Deflection (inches) Reaction (kn) Rubber compound composition is the key Performance factors are compound specific They can t be copied They vary between manufacturers Longevity Efficiency of fender Rubber composition Performance test results Temperature Factors Velocity Factors It s difficult to prepare test samples from commercial fenders without destroying them 7

Analytical test of rubber compound Chemical analysis of samples to understand and distinguish quality Chemical analysis: 50gms of rubber sample, cut from fender body and sliced into small pieces

8 Analytical test of rubber compound Chemical analysis of samples to understand and distinguish quality Chemical analysis: 50gms of rubber sample, cut from fender body and sliced into small pieces Testing equipment What does it do? Rubber % and type Filler % Ash % (Caco3 by chemical analysis) Oil % Recipe for high quality rubber Antioxidant Vulcanization Accelerator (ulphur) Ingredients % Raw Rubber (Polymer) Filler (Reinforcing) Oil (Functional Additives) Others ( + ACC etc) 10-5 Total 100 Function Additive Carbon black Filler (Reinforcement) Natural rubber/ ynthetic rubber Polymer Compounding tructure 8

Types of raw rubber used for manufacturing

from trees Virgin rubber, pure rubber, raw

tyrene-butadiene rubber derived from oil

levels of contamination and uncontrolled

9 Types of raw rubber used for manufacturing Natural Rubber Produced from latex harvested from trees Virgin rubber, pure rubber, raw rubber Raw Rubber ynthetic Rubber (BR) tyrene-butadiene rubber derived from oil Reclaimed Rubber Recycled rubber with high levels of contamination and uncontrolled content Low quality, low cost substitutions of rubber Reclaimed Rubber 18 9

10 Low quality, low cost substitutions of filler: A common cost reduction method Calcium Carbonate. That will be turned in to ash. ize nano Fillers meter for carbon black and CaCo3 is micro size so 1000 times bigger. CaCO 3 CaCO 3 CaCO 3 CaCO 3 CaCO 3 19 uperior quality rubber composition uperior More rubber and less filler Inferior Less rubber and more filler Rubber: filler > 1.00 Rubber: filler < 1.00 No/low % recycled rubber Low/no non-reinforcing white filler (CaCO 3 ), less ash High % of recycled rubber High % of white filler (CaCO 3 ), more ash Density < 1.20 Density > 1.20 Two important indicators of quality for fenders (NR/BR based) Rubber: filler ratio: >1.20 Density: <

11 Testing of Rubber Composition Chemical composition of fenders from ports around the world have been investigated Observations: Differences found in physical appearance Deterioration noticed due to variability in composition and use of inferior compounds Rubber: filler ratio of cell fender samples (60 fenders tested.) (Australian Port) < 1.2 indicates: Poor quality of fender rubber (1,3/0,9=>44,4% more rubber) 1,40 1,20 1,00 0,80 0,60 0,40 0,20 0,00 Low cost fender High cost fender 11

12 Density of cell fender samples (Australian Port) > 1.2 indicates: Poor quality of fender rubber 1,30 1,28 1,26 1,24 1,22 1,20 1,18 1,16 1,14 1,12 Low cost fender High cost fender New specification Chemical composition of rubber compound Test tandard pecification Density IO 2781 Max 1.20 g/cc Polymer % ATM D6370 Min 45% Carbon black % ATM D6370 Min 20% Ash % ATM D297 Max 5% Rubber filler ratio >1.2 12

Proposed test procedure for chemical analysis Before production upplier provides a tensile slab (150mm L x 150mm W x 2+2mm T) Tensile slab sent to a third party lab for chemical analysis (TGA and

13 Proposed test procedure for chemical analysis Before production upplier provides a tensile slab (150mm L x 150mm W x 2+2mm T) Tensile slab sent to a third party lab for chemical analysis (TGA and FTIR) After production The client / third party inspect fenders and randomly select one or two fenders 50 g of sample cut and sent to third party lab for chemical analysis Test result should satisfy the specification of before production samples Conclusion Performance factors (VF/TF/AF/efficiency) are important and must include in fender design and selection process Performance factors are highly dependent on chemical composition of rubber Low cost implies inferior quality of rubber In addition to the current mechanical properties, chemical properties of rubber needs to be included in the material specification. Chemical composition needs to be verified by analytical tests obtaining samples from the commercial fenders 13

14 Whats next in the World of Fenders Environmental aspects?. Trelleborg Marine ystems, have removed all the carcinogenic materials from our formulations, as per the REACH requirement The content of all the chemical used in our formulations are below the limit suggested by REACH. (Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) is a European Union regulation dated 18 December 2006.)REACHaddresses the production and use of chemical substances, and their potential impacts on both human health and the environment). 14

Alcoa Mosjøen Harbor Remediation Project Information and Fender Design

Alcoa Mosjøen Harbor Remediation Project Information and Fender Design Trygve Isaksen and Maiken Eng, Norconsult 1 Content Short presentation of Norconsult, Port and Coastal Engineering and Trygve Introduction