to MERL’s first newsletter of 2011.
This year we are celebrating 25 years as a
leading international polymer specialist for mechanical testing,
chemical testing and Finite Element Analysis services for
materials, components and small structures.
Significant growth in recent years has been
spread across many industry sectors but has been concentrated
in niche areas such as the use of composites in aircraft
and renewable energy systems, elastomers in rail applications,
structural adhesives in automotive applications (for light
weight structures to meet low emission targets), evaluation
of materials used for Carbon Capture and Storage applications
and Enhanced Oil Recovery, subsea reliability testing, sour
gas (H2S) testing and materials used in extreme conditions
(Arctic, deep water, extreme high pressure & temperature).
This Spring 2011 newsletter highlights some
of the projects and technologies that MERL staff are currently
Using lasers to save
When and how
Are we storing
for the future?
What does supercritical CO2 do to my polymers?
New pipe burst test facility
MERL Oilfield Engineering
Polymers Conference 2012
lasers to save weight - Laser welding of polymers
Since adhesive bonding of most thermoplastics cannot
be performed without extensive surface preparation, mechanical
fastening is usually the obvious choice when using traditional
joining techniques. However, a number of new joining techniques
like ultrasonic, resistance or induction welding have been investigated
for manufacturing reliable high performance components. Laser
transmission welding is a technique with great potential for
joining reinforced or un-reinforced thermoplastic components,
offering the possibility of a flexible, controllable and contact
free process with high automation potential.
MERL is expanding its testing and analysis expertise
into assessing the strength and durability of laser welded thermoplastic
components intended for aerospace, automotive and oil and gas
applications. Testing and analysis methodologies developed within
this programme will aim to improve the understanding of the performance
of welded thermoplastic composite structures and assist on optimising
For more details of the LaWocs project or other
mechanical testing facilities please contact Peter
and how will my component fail? – MERL Finite Element
Finite element Analysis services are fully complemented
by a wide range of testing services for generating required material
model data and also for validation of analysis predictions. An
example of an application of FEA for applied engineering solutions
is the modelling and durability assessment of a spherical coupling
joint used in rail vehicles. The use of fracture mechanics as the
basis for assessing fatigue life was used. Components and structures
are modelled using finite element analysis and the fracture mechanics
parameters are obtained and used to calculate fatigue life.
For the fracture mechanics approach,
the damage model is represented by the relationship between the rate
of crack growth and the strain energy release rate or tearing energy.
spherical coupling is subject to a complex set of fatigue conditions.
methodology enabled the various parts of the fatigue loading
to be assessed and the most damaging contributions and mode of
failure to be identified. The approach also enabled the potential
benefits of redesigning the component to be assessed. Testing
the original and redesigned component enabled the analysis results
to be verified. From this, a significant increase in operating
life was demonstrated and the new parts are currently in service.
For more details please contact Dr
novel thermoplastic hydrogen storage tanks for on-board vehicle
The partners in the TSB Durastor project include
MERL, EPL Composite Solutions (Lead Partner), Crompton Technology
Group Ltd, Ticona UK Ltd, Delta Motorsport Ltd, Crompton Mouldings
Limited, Oxford Brookes University.
Major achievements so far include the following:
• The prototype vessel and its components
have been designed.
• Vessel liners have been manufactured.
• Prototype boss components have been manufactured.
• A winding path for the reinforcement layer has been designed.
• Winding trials have now commenced.
Complete prototype vessels are expected to be manufactured
by January 2012, and tests to validate their performance are
expected to be completed by August 2012.
MERL’s role in the project is to perform
the mechanical testing of the candidate materials (liner and
composite materials) as well as testing of the finished tanks.
High pressure permeation tests have been performed with 700
bar hydrogen using samples taken from injection moulded plaques
of material as well as from moulded tank liners. Tests on the
moulded tanks will be performed including permeation tests,
burst tests, impact tests, penetration tests and a bonfire
test. The test methods and facilities developed for hydrogen
storage tanks will also be applicable to other high pressure
tanks and pipes for other industry sectors and will compliment
other MERL facilities and expertise in testing materials and
products to be used in demanding environments.
For more details of the Durastor project please
contact Peter Hansen
Tidal turbines work very much like submerged wind
turbines, however, they are driven by the flow of water rather
than air. They can be installed either in areas with high tidal
currents or in places with continuous ocean currents to harness
the energy from the vast volumes of flowing water. Increasing
energy generation efficiency of these systems is very important
to meet targets on renewable energy generation set by governments
around the world.
The blades of the tidal turbine are generally manufactured
from carbon and glass fibre reinforced composite materials and
operate in a very hostile environment for extended life spans.
Tidal turbines are designed for a 25 years life span and can
be installed in depths of 100 m depth. They are also subjected
to fatigue loading throughout their service life.
MERL has been developing suitable methodologies
for predicting the fatigue life of composite elements subjected
to uni-axial loading as well as the effects of seawater exposure,
high cycle fatigue evaluation, adhesive bonding of dissimilar
materials and designing parts with large thickness changes through
ply terminations. This work builds on many years of design, analytical
and testing expertise with working for aerospace, automotive
and marine industry clients.
For more details on this project or other enquiries
regarding fracture and fatigue testing of composites contact
Dr Stefanos Giannis
we storing up problems for the future? - Carbon Capture and
Storage and Enhanced Oil Recovery
MERL have recently finished a 3 year, UK government (TSB) funded
project (Polymers for Enhanced Oil Recovery - PEOR) investigating
the effect of supercritical CO2 on polymers used for Enhanced
Oil Recovery in the North Sea with partners Baker Hughes, PPE
and Clwyd Compounders.
This project was initiated in response to the increasing use
of EOR using infrastructure that was not qualified for such use.
This is particularly relevant for the polymers involved which
would have originally been specified for hydrocarbon service
and may not necessarily be expected to perform well in high pressure
The project studied the CO2 rapid gas decompression resistance
as well as steam and hydrogen sulphide resistance of candidate
polymers and also developed polymers with improved properties
for these severe conditions. Suitable test equipment and measuring
systems were used to subject test polymers to the fluids at high
pressure and high temperature to investigate any damaging effects.
Volumetric, physical change and mechanical properties were monitored
as a function of exposure condition. MERL now also possesses
a special sapphire-windowed pressure vessel which allows visual
observation of changes whilst materials are exposed to CO2.
A Joint Industry Project (called Polymers for Enhanced
Oil Recovery and Carbon Capture and Storage Applications - PECA)
is being initiated in 2011 to characterise a wide range of polymers
in EOR and CCS conditions to provide a materials data base with
a search-and-sort front end interface.
For more details on the Joint Industry Projects or on the facilities
available contact Glyn Morgan
does supercritical CO2 do to my polymers? - CO2 Testing
When extracting oil and gas from underground, carbon
dioxide is often part of the produced fluid. In recent years
the amount of CO2 produced from reservoirs and the temperature
and pressure at which it flows into the production system have
all increased. Under these conditions, CO2 can be a supercritical
fluid which behaves like a gas but has liquid-like solvating
power. This has become a concern for the polymers used in components
for oil and gas exploration and production because excessive
swelling or change in mechanical performance of these polymers
as a result of interaction with the supercritical fluid could
affect their functionality.
These facilities compliment the other high pressure test facilities available
at MERL that can handle most fluids and gases including sour gas,
ammonia and acids. For more details on the Joint Industry Projects
or on the facilities available contact Glyn
pipe burst test facility
A common problem with performing burst (and crush)
tests on composite pipe sections is the seal design used for
the pressure containment. Composite pipes typically have a relatively
rough outer surface which is difficult to seal onto, especially
with the pressures required to burst or crush these pipes. MERL
has developed a seal design which incorporates pressure-energised
double seal technology, with porting in the end fittings to enable
temperature (if required) and pressure to be monitored and recorded
with time. The pipe is pressurised at a controlled rate until
failure of the pipe is achieved. The assembly is enclosed within
a secondary vessel to contain the sudden release of pressure
upon failure.The current facility accommodates up to 80mm bore
pipes, with burst pressures of greater than 700 bar being achieved
using water as the pressurising fluid. The facility can be scaled
up to accommodate larger diameter pipes according to client requirements.
For more details contact Morris
Oilfield Engineering with Polymers Conference 2012
The 8th MERL Oilfield Engineering with Polymers
2012 conference provides a unique opportunity to present work
to industry peers, to get up to date information on industry
trends and to network with experts from oilfield operators, contractors,
equipment and component manufacturers and materials suppliers.
Current themes for the 2012 conference include:
•handling of supercritical CO2
•operating in extreme environments (arctic conditions, HPHT, sour fluids
•increasing use composite materials
•development of new materials
•rapid gas decompression resistance
•qualification testing and long-term reliability.
If you are interested in presenting a technical paper at the 2012 conference
then please contact Dr John Harris To
be included in the mailing list for the conference please send an email
to firstname.lastname@example.org with ‘MERL Oilfield Engineering with
Polymers’ in the title.