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Oilfield Technology
August
2015
These issues are compounded by more demanding well integrity
legislation, following high profile related incidents.
Whilst mature brownfield assets are the traditional focus for
such issues, the well integrity of new wells is of equal importance –
particularly in challenging HPHT or deepwater environments. After
all, integrity spans the whole lifecycle of a well. Hence, even before a
well can be drilled, there is need to assess future well integrity risks
and to ensure that appropriate integrity policies and engineering
solutions have been considered and factored into the well design and
operating procedures. In fact, how a well is drilled greatly affects the
nature of issues that can arise during production.
By NORSOK definition, well integrity is the: ‘Application of
technical, operational and organisational solutions to reduce risk of
uncontrolled release of formation fluids throughout the lifecycle of a
well.’ In more simplistic terms, it is about identifying and eliminating
potential leaks. Well integrity management systems are therefore
designed to prevent formation fluids breaching barriers and moving
to where they should not be.
Recent studies have shown that 760 000 wells globally are
affected by well integrity related problems – resulting in 19% of these
wells being shut-in.
1
In purely economic terms, these issues currently
cost operators US$1.1 billion/d in lost production revenue.
2,3,4
An earlier study carried out by SINTEF, the Norwegian
Scientific Research Organisation, in 2006 found that between 40%
and 50% of wells in the North Sea and Gulf of Mexico have integrity
problems.
However, globally, this is a mixed and often incomplete picture.
In an academic paper from the Durham Energy Institute last year
5
,
the authors highlighted that global datasets on well integrity vary
considerably in terms of the number of wells examined, their age and
their designs. Therefore meaning the overall percentage of wells that
have some form of well barrier or integrity failure is ‘highly variable –
from 1.9% to 75%’.
Key challenges observed by operators and service companies
in managing well integrity usually relate to data accessibility and
accuracy. For well integrity risks to be understood and known, it
is essential that correct information about the well is recorded
throughout its life and that operating parameters be reviewed and
updated on a regular basis.
Software systems provide an excellent platform to share such
information across an organisation, but also provide engineers and
managers with a tool to make informed decisions. With the current
economic climate and the impact of the oil price on the industry,
the value of understanding
and proactively addressing
well integrity issues has never
been so important.
Systemsandsolutions
The overarching drivers
behind ensuring well integrity
are typically related to safety,
environmental stewardship,
compliance to legislation and
risk mitigation. A management
system that identifies issues,
recommends solutions, and
creates a clear audit trail of
documentation that meets
company and regulatory
requirements satisfies these
needs.
Expro’s software system, SafeWells™, was developed directly
with clients to support their well integrity management processes
and provides a technical, operational and organisational solution to
reduce well integrity risks.
By openly collaborating via a regular user forum, SafeWells
has been developed in line with operator requirements, legislation
and industry best practices. This collaboration between operators
and Expro has ensured that the resulting system is fit for purpose,
practical and user friendly.
The software systemmonitors and reports well integrity
performance and has been successfully deployed by a wide range
of independent and major operators across the globe. It allows the
monitoring of maintenance and associated remedial actions, risk
assessment needs, dispensations and changes in the well operating
envelope.
For management reporting, SafeWells provides an on-screen
‘traffic light’ display of well status according to designated well failure
models, with specific parameters set by the operator. It also has the
ability to communicate via email details of the well status to any
number of chosen personnel.
Operators can therefore anticipate and plan intervention
activities safe in the knowledge that they are compliant with their
policies, while being able to demonstrate effectiveness at monitoring
and tracking their wells’ status.
Collaborationviadatasharing
In recent years there has been a shift in collaboration between
software vendors and operators towards data sharing. This is a vital
step forward for the security of the industry – it is important to work
together in synergy to gather data, analyse information, and apply
solutions in terms of tools, technology and people, in a streamlined
process.
The SafeWells Integration Framework has been developed to
easily allow data to be shared between SafeWells and third-party
software systems. This framework utilises a service-oriented
architecture approach to allow data to be shared between software
systems that specialise in completion design, annulus pressure
monitoring, reliability and maintenance.
The key to the integration framework is the use of web services.
Web services provide a standardised way of integrating software
applications online. Unlike traditional models, web services do not
provide a graphical user interface, but rather share information
through a standardised interface across a network. Developers can
Figure 1.
SafeWellsWell Summary Dashboard showing failed swab valve and subsurface safety valve.
