SAMPO - Safety criteria and improved ageing management ... · SAMPO - Safety criteria and improved...
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SAMPO - Safety criteria and improved ageing management research for polymer components exposed to thermal- radiative environments Konsta Sipilä and Jason Ryan Polymers in nuclear applications 2019, Espoo, Finland 27.11.19 29.11.2019 VTT – beyond the obvious 1
Transcript of SAMPO - Safety criteria and improved ageing management ... · SAMPO - Safety criteria and improved...
SAMPO - Safety criteria and improved ageing management research for polymer components exposed to thermal-radiative environments
Konsta Sipilä and Jason Ryan
Polymers in nuclear applications 2019, Espoo, Finland 27.11.19
29.11.2019 VTT – beyond the obvious 1
SAMPO
WP1 - Acceptance criterion and safety margin assessment
T1.1 – Improved estimation for lifetimes of critical polymer components
T1.2 – Sensitivity of polymer properties to additive
content and methods to verify polymer quality
T1.3 – Setting up safety margins for O-rings
WP2 - Improvements in ageing management of polymer
components
T2.1 – Online condition monitoring techniques
T2.2 – Sensitive analysing techniques
T2.3 – Improved interpretation of non-
destructive testing data
WP3 - International cooperation
T3.1 – Polymer ageing in NPP applications – event
organization
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WP1 - T1.1 Improved estimation for lifetimes of critical polymer components (RISE)
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Communicate with Nordic
Power Plants to assess their needs and
gauge opinions
Select and design tests and
test schedule for chosen materials
Tests of materials, natural vs.
accelerated ageing.
Adaption of current plan
using ongoing results
Finalise lifetime estimation of
critical components
from results so far
Year 1 Year 2-3 Year 4Year 1-2
WP1 - T1.1 Improved estimation for lifetimes of critical polymer components (RISE)
Ringhals summary Cables:
• New cables are being used (Ringhals – Nexam). More information is needed, so far knowledge is they are polyolefin and indent measurements work poorly.• PVC cables exist still in Ringhals 2 and would be interesting to analyse once available (R3 & R4 however have the new cables already).
Membranes:• Changed relatively often – material is available to be tested at RISE.• Membranes more interesting than o-rings – more critical towards crisis situations.• Specifically, the membrane reinforcement exists as the more vulnerable part of the membranes.
Loss of coolant accident (LOCA)• Materials need to be tested to LOCA specification – can be done on some already naturally aged materials from Ringhals and accelerated aged materials.
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WP1 - T1.2 Sensitivity of polymer properties to additive content and methods to verify polymer quality (VTT)
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State-of-an-art on used
additives, their role in ageing mechanisms
and techniques used in additive
analysis
Identify those additives that
contribute most significantly to the ageing of
polymers
Sensitivity analysis of applicable techniques
Suggest practical analysis
techniques for on-site
purposes
Year 1 Year 2-3 Year 4Year 1-2
WP1 - T1.2 Sensitivity of polymer properties to additive content and methods to verify polymer quality Additives can be categorized in several ways, e.g. additives used in
processing, improving mechanical, chemical, surface or visual properties etc. Which additives contribute into the ageing process?
• The observed effects of ageing on the macroscopic level is typically due to the degradation of the polymer backbone• The role of antioxidants• Loss of plasticisers (mostly PVC but also some elastomers)• Defluorination and dechlorination
Different analysis techniques can be categorized to be• Chromatographic (sample preparation)• Organic mass-spectrometry• Spectroscopic (UV, IR, LS, NMR)• Elemental analysis
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WP1 - T1.3 Setting up safety margins for o-rings (RISE)
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Verify COMRADE
results with standard methods
Attain and begin tests on model o-ring
materials.
Use year 1 test results to
design and perform
several new test series.
Finalise tests and confirm suggested
safety margins for o-
rings based on results.
Year 1 Year 2-3 Year 4Year 1-2
WP1 - T1.3 Setting up safety margins for o-rings (RISE) O-rings:
• COMRADE repeat tests are soon finished (Mid-December). Results will be compared to non-standardised test methods.• ‘Disturbed’ COMRADE materials are being standardised tested also.• Model ‘bad’ o-ring material is being set up to be tested, sheets arrive soon (for standardised compression-set tests). – previous COMRADE o-rings tended to not fail under any circumstance, model ‘bad’ material will allow the current test applicability to be confirmed.
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WP2 - T2.1 Online condition monitoring (RISE)
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Literature study on available online
monitoring technologies from
literature and industry.
Discover which are applicable
(together with Nordic Power
Plants).
Experimental tests on model materials from suppliers, real
samples from Plants, and
accelerated aged samples.
Finalise selected methods and
develop/finish prototype setups.
Year 1 Year 4Year 2-3
WP2 - T2.1 Online condition monitoring (RISE) Literature study:
• In the mature stages of completion – several methods have been identified. Henrik will discuss this further in his talk.
Ringhals technical discussion highlights:• Antenna sensors – properties change with ageing, RFID tags could be used for membranes.• Electric-length (LIRA) – already used to find hotspots, long cable lengths required.
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WP2 – T2.2 Sensitive analysing techniques (RISE)
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Development of the
Microcalorimetry technique with materials from COMRADE &
others.
Use model ‘bad’ materials and any
others attained from suppliers, Plants etc. and
compare results to traditional methods.
Finalise method and verify validity
towards accelerated ageing
method supplementation.
Year 1 Year 4Year 2-3
WP2 – T2.2 Sensitive analysing techniques (RISE) Microcalorimetry:
• Essentially differential scanning calorimetry (DSC) but far more sensitive.• Intended to detect degradation in materials via heat transfer (enthalpy).• Intended to analyse at closer to real-life operating temperatures for materials.
Current work:• Several materials have been/are being analysed. Validity looks promising with degradation seemingly present. However, more work needs to be done to assure truth to data.• Temperature ranges are being screened to see if would have an affect on proposed lifetimes.
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Methodology
IsothermalMicrocalorimetery (IMC)
0102030405060708090
0
0.5
1
1.5
2
2.5
0 25 50 75 100
THR
[J/g
]
HR
R [m
W/g
]
Time [h]
HRRTHR
Normalised heat flow (mW/g) and Integratedheat (J/g) signal using IMC
WP2 – T2.2 Sensitive analysing techniques (RISE)
Specific senstivity ~ 1000 times higherthan DSC
DSC ~ 40 µW/mg and IMC ~ 4 µW/1000 mg
Results so far:
60
65
70
75
80
85
90
0 0.5 1 1.5 2 2.5 3
Activ
atio
n En
ergy
, Ea
[kJ/
mol
]
Integrated heat [J/g]
3 temperatures
y = -9.7137x + 22.001
-6
-4
-2
0
2.40 2.60 2.80 3.00
Activation energy calculated based on the IMC measurements on EPDM conducted at3 (80, 100, 125 °C) different temperatures.
Property Activationenergy*
Elongation 103 kJ/molCompressionset
94 kJ/mol
*From COMRADE final report
WP2 – T2.2 Sensitive analysing techniques (RISE)
WP2 - T2.3 Improved interpretation of non-destructive testing data (VTT)
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Identify material parameters that are measureable non-destructively
and can be predicted by MD
simulations
Show how non-destructively
measured parameters correlate to ageing of PE
Refine method towards on-site measurements
Year 1 Year 4Year 2-3
WP2 - T2.3 Improved interpretation of non-destructive testing data (VTT)
Technique Measured parameter Applicability withMD simulations
DSC Reaction entalphy, specific heat capacity Easy to moderateIR/Ramanspectroscopy
Vibrational movement of functionalgroups
Hard
NMR Relaxation time (phase composition and dynamics of polymer chains)
Moderate to hard
Ultrasonic E, σ, and ρ EasyDielectricspectroscopy
Permittivity, dielectric loss Easy to moderate
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WP2 - T2.3 Improved interpretation of non-destructive testing data (VTT) DSC and ultrasound techniques to be further analysed
• Reaction entalphy can be used to determine crystallinity degreewhich correlates with ageing• Young’s modulus changes as function of ageing Determination of crystallinity degree and Young’s modulus as
function of ageing (experimentally and MD calculations) Correlation between the degradation of the polymer chain and
macroscopically (and non-destructively) measured materialparameter (crystallinity degree and Young’s modulus)
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WP3 – International cooperation Improve information exchange between between researchers,
power plants, material manufacturers and regulators Event organization since 2016
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