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8/8/2019 APIC17J1 Revision 3
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Thermoplastic Polymers for OFF-SHORE
Flexible Pipes
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RILSAN
, the unique polyamide from ATOFINA, today looks back at a service history of 30
years in the petrol industry. After 14 years of research in a program launched in 1958 by the
French Institut de Petrole, PA11 was chosen as the best material out of several hundred
tested. The combined qualities of flexibility, excellent impact resistance even at low
temperatures, high resistance to ageing and good compatibility to products common to the
petrol industry environment have made RILSAN
an unequaled standard.
For even higher demands, especially when the temperature or combined high temperature
and high water content requirements are too severe, ATOFINA proposes its unique KYNAR
off-shore grade. KYNAR
is a thermoplastic fluoropolymer resin initially developped by
ATOFINA. Its outstanding thermomechanical properties combined with exceptional chemical
and ageing resistance made it possible for KYNAR
to meet the highest demands.
This document is intended to provide detailed technical information on the properties of
ATOFINAs thermoplastic polymers for flexible pipe use. The scope of the technical details is
defined in the “ Specification for Unbonded Flexible Pipe ” - API Specification API 17Jeffective since March 1
st1997.
The diffusion of this document is controlled, that is, the document is available to costumers of
ATOFINA, the flexible pipe manufacturers, and their costumers; the petrol industry.
The data given in this document based on trials carried out in our Research Centres and data
selected from litterature are given to the best of our knowledge and do not contribute or
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Contents page
1. API 17J - Property Requirements for Extruded Polymer materials 4
1.1 Mechanical/physical properties 4
1.2 Thermal properties 4 1.3 Permeation characteristics, compatibility and ageing 5
1.4 Fluid permeability 5
1.5 Blistering resistance 5
1.6 Fluid compatibility 5
1.7 Ageing tests 6
BESNO P40 TLX and BESNO P40 TLXOS 7
2. Mechanical/physical properties 8
2.1 Density 8
2.2 Hardness 8
2.3 Compression strength 8
2.4 Abrasion resistance 8
2.5 Flexural test according to ISO 178-93 8
2.6 Flexural test according to ASTM D790 8
2.7 Impact test according to ISO 179 (type II) 8
2.8 Impact test according to ISO 179-93 CA 8
2.9 Tensile creep 92.10 Stress relaxation 12
2.11 Fatigue 13
2.12 Tensile tests according to ISO 527-93 BA 14
2.13 Tensile tests according to ASTM D638 type II 14
2.14 Poisson ratio 14
2.15 Compression test 17
2.16 Creep in compression mode 18
3. Thermal properties 20
3.1 Thermal conductivity 20
3.2 Thermal expansion 20
3.3 Heat deflection temperature ASTM D648 20
3.4 Softening point ASTM D1525 20
3.5 Heat capacity 20
3.6 Glass transition temperature 20
3.7 Dynamic mechanical analysis 213.8 Differential Scanning Calorimetry (DSC) 22
4. Ageing behaviour, compatibility and permeation 23
4.1 Lifetime models and end-of-life criteria based on polyamide hydrolysis 23
4.2 Evolution of properties during ageing 25
4 3 C tibilit ith ff h fl id d 28
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1. API 17J - PROPERTY REQUIREMENTS FOR EXTRUDED POLYMER
MATERIALS
The API specification 17 J “ Specification for unbonded flexible pipe ” was edited in december
1996 and is effective since 1st of march 1997. The intention of this specification is the
harmonization of current practice in the off-shore industry with the particular aim of obtaining high
safety standards and a common reference basis for all suppliers to the off-shore industry.
The API specification 17 J contains a specific chapter 6.1.2 dealing with polymer materials.
ATOFINA, a supplier of polymer materials to the off-shore industry, is adressing the specified
properties in this given document.
1.1 MECHANICAL/PHYSICAL PROPERTIES
Internal pressure sheath : A, Intermediate sheath / Anti-Wear layer : B,
Outer sheath : C
A B C Test Procedure Comments
Resistance to creep X X X ASTM D2990 due to temperature
and pressure
Yield strength/elongation X X X ASTM D638
(ISO 527 93.1 BA)
Ultimate strenth/elongation X X X ASTM D638Stress relaxation properties X ASTM E328
Modulus of elsticity X X X ASTM D790
(ISO 178 :39)
Hardness X ASTM D2240
(ISO 2039/2 et 868)
Compression strenth X ASTM 695
Impact strength X ASTM D25
(ISO 179 type1 et
ISO 179 :93CA6
at design minimum
temperatures
Abrasion resistance X ASTM D4060
(ISO 9352 :1995F)
or ASTM D1044
Density X X X ASTM D792 ASTM D1505
Fatigue X X X ASTM D671 dynamic applications
only
Notch sensitivity X ASTM D256
1.2 THERMAL PROPERTIES
Internal pressure sheath : A, Intermediate sheath / Anti-Wear layer : B,
Outer sheath : C
A B C Test Procedure Comments
Coefficient of thermal conductivity X X X ASTM C177
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1.3 PERMEATION CHARACTERISTICS, COMPATIBILITY AND AGING
A B C Test Procedure Comments
Fluid permeability X X X details in API 17J CH4, CO2, H2S and
methanolBlistering resistance X details in API 17J at design conditions
Fluid compatibility X X X details in API 17J
Aging tests X X X details in API 17J
Environmental stress cracking X X X ASTM D1693
weathering resistance X Effectiveness of UV
stabilizer
Water absorption X X ASTM D570 Insulation material
only
For the characteristics listed in the last table API 17J recommends the following test requirements.
1.4 FLUID PERMEABILITY
a) The sample shall be taken from an extruded polymer sheath.
b) The thickness is 1 mm as a minimum.
c) The diameter is 70 mm as a minimum.
d) Sufficient tests at different temperatures to allow for linear interpolation should be performed.e) Sufficient tests at different pressures to allow for linear interpolation should be performed.
1.5 BLISTERING RESISTANCE
a) Fluid mixtures - Use gas components of specified environment as documented in the test
procedure..
b) Soak time - Use sufficient to ensure stauration.
c) Test cycles - If available, use expected number of decompressions, or else use 20 cycles as aminimum.
d) Decompression rate - If available, use expected decompression rate, or else use as a minimum
70 bar per minute.
e) Thickness - Internal pressure sheath wall thickness as a minimum.
f) Temperature - Use the expected decompression temperature.
g) Pressure - Use design pressure as a minimum.
h) Procedure - After each depressurization the sample shall be examined at a magnification of ×
20 for signs of blistering, swelling and slitting. No blister formation or slitting shall be observed.
1.6 FLUID COMPATIBILITY
All components shall be evaluated in the environments to which the polymer is exposed. Tests shall
be based on the design conditions of temperature pressure and strain As a minimum tensile
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1.7 AGEING TESTS
Polymer aging models shall be based on testing and experience and shall predict the aging or
deterioration of the polymer under the influence of environmental and load conditions that have
benn identified to be relevant through testing. As a minimum, polymer aging models for PA-11
shall consider temperature, water cut and pH. For PVDF materials the assessment of aging shall
include the effect of temperature, chemicel environment and mechanical load. Special attention
should be given to deplastification, fluid absorption and changes of dimensions. Creep, cyclic strain
and relaxation shall be investigated on aged and unaged samples. The aging models may include
accumulated damage concepts based on blocks of time or operational cycles of
temperature/pressure under different exposure conditions. Aging may be determined by change in
either specific mechanical properties or in specified physico-chemical characteristics whichincludes reduction in the plasticizer content of the material.
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BESNO P40 TLX
BESNO P40 TLX OS
DATA
BESNO P40 TLX and BESNO P40 TLX OS are both plasticized PA11 grades
destinated for off-shore flexible pipe use. Their respective compositions are strictly the
same as well as their properties. Th difference between the two grades lies in different
granules’ conditioning for shipment.
In general and in case it is not specifically stated, experiments were conducted on
extruded sheet material. Such extruded sheet gives similar experimental results as the
extruded flexible pipe.
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2. MECHANICAL/PHYSICAL PROPERTIES
2.1 DENSITY
ASTM D792 1.05
2.2 HARDNESS
ISO 2039/2 (R SCALE) 75
ISO 868 (D SCALE) 63
2.3 COMPRESSION STRENGTH
ASTM D695 (23°C) 50 MPa
2.4 ABRASION RESISTANCE
ISO 9352 : 1995(F)
(loss in weight after 1000 rev under 500g
load with H18 abrasive wheel) 22 mg
2.5 FLEXURAL TESTS ACCORDING TO ISO 178 : 93
Temperature °C -40 -20 23 80Flexural modulus
(dry material)
MPa 1950 1350 320 165
Flexural modulus
(after conditionning 15
days 23°C 50% R.H.)
MPa 2050 1150 280 160
2.6 FLEXURAL TESTS ACCORDING TO ASTM D790
Temperature °C 23 80
Flexural modulus
(dry material)
MPa 330 170
2.7 IMPACT TESTS ACCORDING TO ISO 179 (type 1)
Temperature °C -40 23
Unnotched KJ.m-2
N.B. N.B.
Notched KJ.m-2
8 N.B.
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2.9 TENSILE CREEP - TRACTION MODE
Tensile creep tests according to ASTM D2990 were performed under 2 MPa at different temperatures
rangeing from 23°C to 80°C. Tensile specimens were of ISO R 527 injected type and a MTS 810
servohydraulic machine is used. From the different curves a creep master curve was constructed by applying
the time temperature superposition principle. The creep modulus can then be modeled by a linear function ona log-log scale.
Creep curves at 2 MPa for different temperatures - strain data
0
0.002
0.004
0.006
0.008
0.01
0.012
0.014
0.016
1 10 100 1000 10000 100000
TIME (s)
S T R A I N ( m m / m m )
23°C 30°C 40°C 50°C 60°C 80°C 100°C
Master plot at 2 MPa obtained using the time - temperature shifting principle scaled to 23°C
00.0020.0040.0060.0080.01
0.0120.0140.016
1 100 10000 1000000 1E+08 1E+10 1E+12 1E+14
S T R A I N
( m m / m m )
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Plot of the shifting factor αΤ used to obtain the maste plot
01
234
567
89
10
0.0025 0.0027 0.0029 0.0031 0.0033 0.0035
1/T K-1
l o g ( a T )
Creep curves at 2 MPa for different temperatures - stress data
100
1000
1 10 100 1000 10000 100000
TIME (s)
M O D U L U S ( M P a )
23°C 30°C 40°C 50°C 60°C 80°C 100°C
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Tensile creep master curve constructed for 23°C
100
1000
1 100 10000 1000000 1E+08 1E+10 1E+12 1E+14
TIME (s)
M O D U L U S ( M P a )
23°C 30°C 40°C 50°C 60°C 80°C 100°C
All these creep studies have been done on ISO R 527 injection molded samples for purpose
of simplicity but we have checked that there is merely no difference in the creep behaviour
between injection molded or extruded samples.
Tensile creep curves under 5 Mpa at 23°C, 50°C and 80°C for both injection molded and
extruded specimen
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2.10 STRESS RELAXATION
Stress relaxation measurements were performed according to ASTM standard E 328.86, but
using ISO R 527 tensile specimens. The imposed strain was 1%. A stress relaxation master
curve was built using time - temperature superposition principle.The stress relaxation modulus is seen to decrease linearly in time in a log - log plot.
Stress relaxation curves for different temperatures at 1% strain
100
1000
1 10 100 1000 10000 100000
Time(sec)
M O D U L U S ( M
P a )
23°C 30°C 40°C
50°C 60°C Puissance (23°C)
Puissance (30°C) Puissance (40°C) Puissance (50°C)
Puissance (60°C)
Master plot : Evolution of E Modulus during stress relaxation under 1% strain at 23°C
100
1000
1 100 10000 1000000 1E+08 1E+10 1E+12
M O D U L U
S ( M P a )
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Comparison between the creep master plot and the stress relaxation master plot at 23°C
100
1000
1 100 10000 1000000 1E+08 1E+10 1E+12 1E+14
TIME (s)
M O D U L U S ( M P a )
CREEP
STRESS RELAXATION
2.11 FATIGUE
Measured according to NF T51-120 in replacement to the norm ASTM D671. We chose this
standard which measures fatigue at constant deformation in contrast to the ASTM standard
which measures at constant stress. To our knowledge the constant amplitude mode is more
representative to the actual situation in a flexible riser. Furthermore, the constant stress
mode would result in a considerable increase of deformation during the fatigue experiment
due to stress relaxation of the material.
FATIGUE TEST OF BESNOP40TLX WITH AN END OF LIFE
CRITERIA OF 20% REDUCTION OF THE INITIAL STRESS
4.00
5.00
6.00
7.00
8.00
9.00
10.00
L S T R E S S ( M
P a )
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2.12 TENSILE TESTS ISO 527 93.1BASamples injection moulded
TEMPERATURE Yield strength Elongation at
yield
Ultimate strength Elongation at
break MPa % MPa %
-60°C 93.4 10 65.5 75
-40°C 77.3 11 60.8 90
-20°C 49.1 21 59.2 202
0°C 36.4 33.2 56.8 231
23°C - - 48.8 263
40°C - - 43.8 260
60°C - - 37.3 260
80°C - - 34 262
100°C - - 31.9 282
120°C - - 32.7 323
2.13 TENSILE TESTS ASTM D638 type IISamples cut from extruded sheaths
TEMPERATURE Yield strength Elongation at
yield
Ultimate strength Elongation at
break
MPa % MPa %
-40°C 64 16 33 128
-20°C 46 30 > 39 > 230
0°C 36 40 > 39 > 230
20°C 26 44 > 27 > 23040°C 20 46 > 26 > 230
60°C 20 46 > 26 > 230
80°C 13 44 > 17 > 230
100°C 11 42 > 15 > 230
120°C 9 38 > 13 > 230
Apparatus limited in size to reach maximum elongation
2.14 POISSON RATIO
Temperature (°C) -40 23 100
Poisson ratio 0 385 0 47 0 45
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Tensile test according ISO R 527-93 1BA
0
20
40
60
80
100
120
-60°C
-40°C-20°C
0°C
20°C
40°C
60°C80°C
120°C
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Tensile tests according ASTMD 638 type II
0
10
20
30
40
50
60
70
0 50 100 150 200 250 300
S t r e s s ( M P a )
-40°C
-20°C
0°C
20°C
40°C
60°C
80°C
100°C
120°C
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2.16 CREEP IN COMPRESSION MODE
Creep tests in compression were done on 10*10*5 mm specimen machined in an extruded
pipe. The compression is applied along the thickness on an MTS 810 servohydraulic
machine.
Creep in compression mode of BESNO P40 TLX under 10 MPa
0
2
4
6
8
10
12
1 10 100 1000 10000 100000
Time(s)
S t r a i n ( % )
20°C 30°C 40°C 60°C 80°C
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Creep in compression mode of BESNO P40 TLX under 15 MPa
0
5
10
15
20
25
1 10 100 1000 10000 100000
Time(s)
S
t r a i n ( % )
23°c 30°c 40°c 60°c 80°c 100°c
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3 THERMAL PROPERTIES
3.1 THERMAL CONDUCTIVITY
Temperature (°C) 39 61 82 102 122 142 163 182 202 223
K (W/m°K) 0.21 0.21 0.24 0.24 0.24 0.24 0.25 0.25 0.25 0.25
3.2 THERMAL EXPANSION
ASTM E 821from -30°C to +50°C 11x10-5 °K -1
from +50°C to +120°C 23x10-5 °K -1
3.3 HEAT DISTORSION TEMPERATURE
ASTM D648
ISO 75 (0.46 Mpa) 130 °C
ISO 75 (1.85 Mpa) 45 °C
3.4 SOFTENING POINT
ASTM D1525
under 1daN 170 °Cunder 5 daN 140 °C
3.5 HEAT CAPACITY
Measured by D.S.C.
Temperature (°C) 20 50 80 120 160 200 230 260
cal/g.°C 0.40 0.50 0.56 0.6 0.63 0.66 0.66 0.67
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3.7 DYNAMIC MECHANICAL ANALYSIS (full curve)
Measurement in a 3-point bending flexural mode at 10 rad/s
1.00E+07
1.00E+08
1.00E+09
1.00E+10
- 1 4 0
- 1 2 0
- 1 0 0
- 8 0
- 6 0
- 4 0
- 2 0 0
2 0
4 0
6 0
8 0
1 0 0
1 2 0
1 4 0
1 6 0
1 8 0
Temperature(°C)
S T O R A G E M O D U L U S E
' ( P a ) , L O S S
M O D U L U S E ' ' ( P a )
E'
E''
The DMA curve obtained is characteristic for semicristalline polymers. Essentially four
different relaxational transitions can be detected.
The γ transition at the lowest temperature (-130°C) is commonly attributed to localizedmotion of methylene segments. The intermittent low temperature relaxation, denominated
β- relaxation, is attributed to localized motion of H-bonded groups like the amide functions
and its amplitude varies depending on water content.
The α-relaxation around -10°C is also called the glass transition. It implies large segmental
motion of the polymer chains enabling diffusion processes to take place .
Finally the last transition with an onset at 140°C is linked to the melting of the cristalline
phase.
For a textbook on the comprehensive analysis of DMA data refer to “ Anelastic anddielectric effects in polymer solids ” by N.G. McCrum, B.E. Read, G. Williams Dover
Publication New York 1991.
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3.8 DSC CURVE OF BESNO P40 TLX
The DSC curve is obtained on a PERKIN ELMER DSC 7 calorimeter at a heating rate of
20°C/min. On the thermogram, one can easily observe the melting zone and the melting
peak that gives the melting temperature.
25
30
35
40
45
50
-80 -40 0 40 80 120 160 200 240
Temperature(°C)
H e a
t F l o w ( m W )
Heating rate : 20°C/min
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4. AGEING BEHAVIOUR, COMPATIBILITY AND PERMEATION
4.1 LIFETIME MODELS AND FAILURE CRITERIA BASED ON
POLYAMIDE HYDROLYSIS
From a point of view of material evolution due to ageing the following effects have been
demonstrated in plasticized PA11 :
- molecular weight loss due to a hydrolysis reaction in the presence of water
- plasticizer loss
- absorption of oil components, gases and moisture
- annealing which leads to a higher crystalline content.
Hydrolysis has been reckognized as the most important ageing phenomenon in PA11. The process is well understood due to intense recent research. The kinetics of molecular weight
loss are known in detail and can rather well be correlated with material performance [1 2 3
4].
The importance and the complexity of the PA11 ageing behaviour have resulted in a
combined industry effort. The main result of the industry working group is a document
which states specifically the end-of-life criteria and typical lifetime curves for environmentsof different acidity. The reference of this document is
API Technical Bulletin 17 RUG.
The reference ageing criterion defined is based on average molecular weight as expressed in
Corrected Inherent Viscosity (CIV). Guidelines how to measure CIV are given in detail in
API TB 17 RUG and refer to standards ASTM D2857-95 and ISO 307:1994. However,
special procedures not outlined in the ASTM or ISO standards apply.
The failure criterion for PA11 in flexible pipes has been determined as CIV = 1,05 dl/g. The
initial acceptance criterion has been defined as 1,20 dl/g which includes a safety factor.
For further information, in particular lifetime estimations and Arrhenius curves based on
above acceptance and failure criteria, the reader should refer to API TB 17 RUG.
Special attention is drawn to the necessity of appropriate procedures for ageing
experiments. The oxygen content in long term ageing experiments must be tightlycontrolled and kept below a minimum to avoid a significant increase in ageing severity.
Also the preparation of test samples and factors such as the weigth ratio testing medium /
samples are important parameters. For detailed information please refer to API TB 17 RUG.
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4. "Molecular weight distribution and mass changes during polyamide hydrolysis", G.
Serpe, N. Chaupart, J. Verdu, Polymer, Vol 39 n°6-7, 1375-1380, 1998
5. “Recommended practice for flexible pipe” API 17B, 2nd
edition 1998
6. “Specification for unbonded flexible pipe” API Specification 17J, revised edition 1997
7. “Progress towards a better understanding of the performances of Polyaminde 11 in
flexible pipe applications” S. Groves Proceedings of OMAE’01, n° 3570
8. "Improved thermoplastic materials for offshore flexible pipes", F. Dawans, J. Jarrin, T.
Lefevre, M. Pelisson, Communication OTC 5231, 1986.
9. “Lifetime prediction of PA11 and PVDF thermoplastics in oilfield service– a synthetic
approach” Patrick Dang, Yves Germain, Bernard Jacques, James Mason, Michael R.G.
Werth, American Chemical Society Rubber Division meeting in Dallas, 3/04/2000
10. "Durability of polyamide 11 for offshore flexible pipe applications", J. Jarrin, A.
Driancourt, R.Brunet, B. Pierre, Communication at MERL Oilfield engineering with polymers, London, October 1998.
11. "Ageing of polyamide 11 in acid solutions", G. Serpe, N. Chaupart, J. Verdu, Polymer,
Vol 38 n°8, 1911-1917, 1997
12. "Molecular weight distribution and mass changes during polyamide hydrolysis", G.
Serpe, N. Chaupart, J. Verdu, Polymer, Vol 39 n°6-7, 1375-1380, 1998
13. “Accelerated ageing of polyamide 11 : evidence of physical ageing playing a role in the
end-of-life criteria” H.J. Fell, M.H. Ottoy, Proceedings of Oilffield Engineering with
polymers 2001, MERL Conference 28-29/11/2002-03-1814. “The Rilsan User Group and APUI TR 17RUG” S. Groves, K. Caveny, R. Thompson,
M. Ottoy, J. Rigaud, E. Oeren, J. Belcher, S. Buchner, B. Jacques, M. Werth, D.
Kranbuehl, J. Chang, OTC 14062 6 – 9 may 2002
15. “Polyamide 11 – a high tenacity thermoplastic, its material properties and the influence
of ageing in offshore conditions” M? Werth, G. Hochstetter, P. Dang, N. Chedozeau,
OMAE ’02 –28570 , June 23 – 28 2002 Oslo
16. API TB 17 RUG
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4.2 EVOLUTION OF PROPERTIES DURING AGEING
Tensile properties
For demonstration purposes the evolution of tensile properties in an accelerated ageing
experiment at 120°C in diluted sulfuric acid (pH = 4) are given.ISO R527 samples with 3 mm thickness are machined out of extruded sheath and tesile tests
performed at 23°C and 50 mm/min traction speed.
The data presented shows a limited performance reduction for samples aged for “ and 10
days. However, after 19 days a considerable reduction in elongation is observed. The
material can be considered brittle and not fit for purpose.
Such rather steep transitions between slightly affected aged material and a strong drop in
tensile properties is characteristic of polyamide 11 behaviour upon ageing.Moreover, the ageing performance and CIV are well correlated ; after 19 days the CIV =
0,97 dl/g.
BESNO P 40TL Influence du vieillissement H2SO4/120°C Traction 50mm/min 23°C
Haltère ISO R257 épaisseur 3mm usinée dans tube Coflexip
0
5
10
15
20
25
30
35
40
0 20 40 60 80 100 120 140 160 180 200
Allongement rupture (%)
C o n t r a i n t e ( M P a )
non vieilli
3 jours
10 jours
19 jours
29 jours
40 jours
Ecart-type en pointillés
Fracture toughness
A pertinent property for the flexible application is fracture toughness, in particular at lower
temperatures This method is very sensitive for material changes due to ageing effects
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BESNO P40TL Traction 23°C et 50mm/min
0
20
40
60
80
100
120
140
160
180
200
0.0 0.5 1.0 1.5 2.0 2.5
Viscosité corrigée ISO (dl/g)
A l l o n g e m e n t r u p t u r e
( % )
H2SO4/120°C pH=4 Haltères ISO R527 épaisseur 3mm
Eau/140°C Haltères 53448A Visco cœur
Eau/140°C Haltères DIN53448A Visco peau
Comparison of K1c values obatined on compact test specimen and
charpy bars aged in H2SO4 pH 4 at 120°C and water at 140°C
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0 0.5 1 1.5 2 2.5
CIV (dl/g)
K 1 c ( M P a .√ m )
CT tensile H2SO4/120°C
CT tensile water/140°C
bars charpy water/140°C
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Fatigue experiments
Fatigue experiments have been performed on strips cut from aged pressure sheath in the
extrusion direction and thus including the interior extrusion band on the specimen and also
on strips cut from smooth bore pipes. The specimens are aged to different levels, some cut
from retrived pipes presenting a viscosity gradient. The imposed starting strain is 4 %corresponding to 12.5 MPa. The fatigue cycles are stress controlled and oscillate at 1 Hz
(maximum frequency without self heating) between 10 and 100 % of imposed maximum
stress.
The bars indicate viscosity gradients over the sheath thickness.
The fatigue experiments demonstrate good performance for sheath material above CIV =
1,0 dl/g.
Literature on fracture mechanics with references on methodology :
- ISO task group working on the compact test K 1C method : ISO/TC61/SC2 n° 572, ISO/DIS
13586-2,1998 : Determination of Fracture Toughness (Gc and Kc) Linear Fracture Mechanics (LEFM) Approach
- J.G. Williams testing Protocol, march 1990, Mech. Eng. Dept. Imperial College, London- ASTM E 399-81 Standatd test method for plane strain Fracture Toughness of metallic
materials
- J.G. Williams, M.J. Cawood, Polym. Testing, 9, 15 (1990)
- J.G. Williams “Fracture Mechanics of Polymers” Ellis Horwood Ltd. Chichester (1984)
ISO/TC61 N5015 Pl ti T t th d f T i T i F ti C k P ti
Tensile fatigue : samples cut from pipe and sheath
aged in benzoic acid at 120°C
0
50000
100000
150000
200000
250000
300000
350000
400000
450000
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8
CIV (dl/g)
N u m b e r
o f c y c l e s t o r u p t u r e
pipe 864N
sheath 864N
no break
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4.3 COMPATIBILITY
The compatibility of RILSAN® offshore grades BESNO P40 TLX, BESNO P40 TLO,
BESNO P40 TL is specified in detail in a separate document :
RILSAN® Polyamide 11 in Oil & Gas
OFF-SHORE Applications Reference © 2001/11/08.
This document gives comprehensive information on ageing of polyamide 11 in all offshore
environments. Furthermore, information is given relative to diverse injection fluids used in
combination with thermoplastic umbilicals.
Reference
“A more realistic method for predicting the compatibility of thermoplastic hoses when usedin subsea umbilical systems” J.D. Stables, I.R. Dodge, D. MacRaild OTC 7272 1993
4.4 PERMEATION CHARACTERISTICS
Permeability of gases
Gas permeabilities were measured at the Institut de Pétrole (IFP) France following the“time-lag” method.
Circular samples were cut from extruded sheath. The dimensions were 2 mm thickness and
70 mm diameter.
Details are described in the confidential report n° 52 735, octobre 1999 issued by IFP.
Fluid Conditions Permeation value /
10-8
cm3.cm/cm
2.s.bar
CH4 40°C, 100 bars
60°C, 100 bars
80°C, 100 bars
100°C, 100 bars
0,4.
0,8
2
4
CO2 40°C, 100 bars
60°C, 100 bars
80°C, 100 bars
1,5
4,5
10
H2O 70°C
50 to 100 bars
200 - 700
H2S 80°C, 40 bars 51
The data correlates well with data published elsewhere.
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Permeability of PA11 to methanol
Temperature in °C 4 23 40 50
PA11 unplastizised 6 18
PA11 plastizised 13.5 40 115 190
units : g mm/m2 day atm
The activation energies for the unplasticized and plasticized grades are respectively 39.4 kJ
mol-1 and 43.1 kJ mol-1.
0°C10°C20°C30°C40°C50°C1
10
100
1000
1/Temperature
P e r m e a b i l i t y ( g m m / m 2 d a y a t m ) BESNO TL
BESNO P40 TL
Litterature
17. “Permeability of methane, carbin dioxide and water in PA11 and PVDF for flexible
pipes” T.R. Andersen, J.I. Skar, C. Hansteen, Eurocorr Congress 99, n°410
18. “High pressure permeation of gases in semicrystalline polymers : measurement method
and experimental data” B. Flaconneche, M.H. Klopffer, C. Taravel-Condat, Proceedingsof Oilffield Engineering with polymers 2001, MERL Conference 28-29/11/2002-03-18
19. "Improved thermoplastic materials for offshore flexible pipes", F. Dawans, J. Jarrin, T.
Lefevre, M. Pelisson, Communication OTC 5231, 1986.
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4.5 BLISTERING RESISTANCE
A blistering resistance study was performed at Institut Français du Pétrole (Solaize France).
Material tested : BESNOP40TLX, samples taken from extruded pipe (8 mm thickness)
Conditions :
Sample size 35× 45 × 8 mm
Test medium 85 % CH4 + 15 % CO2
Test temperature 90°C
Test pressure 1000 bar
Soak time > 30 h
Decompression rate explosive , > 70 bars/min
Conclusion :
No blister and no slitting have been observed after 20 cycles of compression –
decompression, the RILSAN® BESNOP40TLX saturated by Diesel type II is qualified at
90°C / 1000 bar toward blistering according to the IFP’s test procedure issued from the API
17 J specification.
4 6 WEATHERING RESISTANCE
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4.6 WEATHERING RESISTANCE
The UV resistance is measured under accelerated conditions on a standardized machine
XENOTEST 1200 according to the RENAULT standard n° 1380.
Conditions :
Xenon lamps with filters eliminating radiation with wave lengths inferior to 300 nm.Intermittent exposure -è equal periods of light and darkness.
During a 20 minute cycle the specimens are exposed to 3 minutes of distillated water spray
and 17 minutes of exposure without spraying. The relative humidity of the cabinet during
period without spray is approximately 65%.
Black panel temperature in the measurement cabinet :
65°C ± 2°C before spraying
45°C ± 2°C after spraying.The specimens are dumbells according to ISO/NFT 51034 cut from a film of 1 mm
thickness. Tensile tests are carried out at 50 mm/minute.
time (h) 0 500 1000 1400 2000
EB (%) 380 330 275 85 33
EB / EB0 1 0.87 0.72 0.22 0.09
MB (MPa) 72 61 47 34 25
YI 6 14 16 13 13
UV ageing : loss of elongation at break
050
100
150
200
250
300
350
400
0 500 1000 1500 2000 2500
time (h)
E B ( % )
4 7 WATER ABSORPTION
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4.7 WATER ABSORPTION
ASTM D570 0.8% (23°C 50%R.H.)
1.6% (23°C saturation)
Water Absorption of BESNO P40 TLX at different temperatures - cinetics
0
0.5
1
1.5
2
2.5
3
0 200 400 600 800 1000 1200 1400 1600 1800 2000
rac t / L (min^0.5/cm)
A b s ( % ) 23°C
80°C
60°C
100°C
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TENSILE CREEP OF RILSAN BESNOP40TLX UNDER 2 MPa
0
0,002
0,004
0,006
0,008
0,01
0,012
0,014
0,016
0,018
1 10 100 1000 10000 100000
TIME (s)
S
T R A I N ( m m / m m )
23°C 30°C 40°C 50°C 60°C 80°C 100°C
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CREEP MASTER CURVE OF BESNOP40TLX UNDER 2 MPa
0
0,002
0,004
0,006
0,008
0,01
0,012
0,014
0,016
0,018
1 100 10000 1000000 100000000 1E+10 1E+12 1E+14
TIME (s)
23°C 30°C 40°C 50°C 60°C 80°C 100°C modele
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TENSILE CREEP OF RILSAN BESNO P40 TLX UNDER 2 MPa
100
1000
1 10 100 1000 10000 100000
TIME (s)
23°C 30°C 40°C 50°C 60°C 80°C 100°C
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TENSILE CREEP MASTER CURVE OF RILSAN BESNOP40TLXUNDER 2 MPa
100
1000
1 100 10000 1000000 100000000 1E+10 1E+12 1E+14
TIME (s)
M O D U L U S ( M P a )
23°C 30°C 40°C 50°C 60°C 80°C 100°C
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SHIFT FACTOR FOR THE CREEP MASTER CURVE
OF BESNO P40 TLX
0
2
4
6
8
10
12
0,0025 0,0026 0,0027 0,0028 0,0029 0,003 0,0031 0,0032 0,0033 0,0034 0,0035
1/T K-1
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BESNO P40 TLX - COMPRESSION CREEP UNDER 10 MPa
0
2
4
6
8
10
12
1 10 100 1000 10000 100000
Time(s)
23°c - 10 MPa 40°c -10 MPa 60°c- 10 MPa 80°c -10 MPa 30°c-10 MPa 23°c - 10 MPa
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CREEP COMPRESSION OF BESNO P40 TLX UNDER 10 MPa
0
2
4
6
8
10
12
1 10 100 1000 10000 100000 1000000
Time(s)
S t r a i n ( % )
23°C 30°C 40°C 60°C 80°C
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BESNO P40 TLX - CREEP IN COMPRESSION UNDER 15 MPa
0
5
10
15
20
25
1 10 100 1000 10000 100000
Time(s)
23°c 30°c 40°c 60°c 80°c 100°c
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COMPRESSION CREEP OF BESNOP40TLX UNDER 15MPa
0
5
10
15
20
25
1 10 100 1000 10000 100000 1000000
Time(s)
S t r a i n ( % )
23°C 30°C 40°C 60°C 80°C 100°C
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DYNAMIC MECHANICAL ANALYSIS OF BESNOP40TLX
(3 POINT BENDING FLEXURAL MODE AT 10rad/s)
1.00E+07
1.00E+08
1.00E+09
1.00E+10
-140 -120 -100 -80 -60 -40 -20 0 20 40 60 80 100 120 140 160 180
Temperature(°C)
S T O R A G E M O D U
L U S E ' ( P a ) ,
L O S S M
O D U L U S
E ' ' ( P a )
E'
E''
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DSC curve of BESNO P40 TLX
25
30
35
40
45
50
-80 -60 -40 -20 0 20 40 60 80 100 120 140 160 180 200 220 240
Temperature(°C)
H e a t F l o w ( m W )
Heating rate : 20°C/min
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