3.1 Data and information

indications of failure and have plans for compensating actions if indications of failure are found. Latest knowledge related to degradation and life extension shall

of the ALE framework and possible outcomes.

identified and used as basis for life extension evaluations.

requirements, the following should, among others, be considered:

• reservoir depletion causing subsidence of the facility

• shallow gas detection and mitigation

and operating conditions

rates in certain systems

• Well and drilling factors

• Plans for increased gas flow

pressure, injection or chemicals

• Changes to the SCEs on the facility

• Changes to equipment usage.

3. An asset life extension program

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A case study is provided within Section 11, to demonstrate a simple application

As the Asset ages, there is increasing challenge to maintaining equipment and installation integrity, compliance with Regulatory requirements and improve economic hydrocarbon recovery from depleted fields. As such, life extension analysis and evaluations must be based on the planned use of the facilities during the life extension period. Changes to the operational conditions that can have an impact on the efficiency of resource exploitation, the risk profile as well as the performance of the barriers due to aging, must be considered. The potential changes to the operational conditions that influence the degradation of barriers must be

Based on Norwegian Oil and Gas Recommended Assessment and Documentation for Service Life Extension of Facilities, Rev1, 2012 [5] and operational data and

• changes in climatic conditions resulting in changes to environmental loadings

• Increased changes in fluid compositions that can adversely affect the corrosion

• Need for new process or utility equipment due to changed flows, chemistry,

The basis for the design and design life of facilities with its associated platform, wells, subsea systems and pipelines may be different. When facilities are planned to be used beyond design life, OGPs should define the life extension period for which

• Changes to the original design assumptions as provided in QRA etc.

• New methodologies to simulate damage and degradation.

be applied.

2. Operational context

Maintenance Management

The collection of data and information is often the most challenging aspects of commencing an ALE study. It is recommended that records be securely placed within an electronic database generally used to manage asset integrity and reliability solutions. The availability and accuracy of information should be evaluated for each facility considered. The information should constitute design basis and specifications, design and as built drawings, design/(re-) analysis reports, inspection reports, maintenance and repair records and specifications. Once these records have

Figure 5. Asset life extension process [6].

been complied, data quality measures should ensure the appropriate data for screening. In some cases, the data analytics and trending measures give a better representation of the data set and how this can be used effectively in an ALE program.

The recommendations from the gap assessment are to cover all the remedial actions necessary to prevent the risk associated with spare strategy, obsolescence related to the equipment and spare parts, remnant life analysis and prediction of future failures modes and degradation mechanism especially related to aging during the extension period. The benefits of applying new technology in addressing the gaps shall be evaluated. This could help mitigate or close gaps with less modifications or compensating measures. The Health and Safety Executive, UK (2013) KP4 Report [7] outlined the following safety management systems as being the barriers

In addition to the above mentioned the following systems may be considered

Oil and gas producers (OGPs) are to perform analyses and evaluations to demonstrate and understand of how the time and aging processes will affect HSE, the facilities barriers including technical operational and organizational aspects and resource exploitation. They shall also identify measures required to mitigate the

The Norwegian Oil and Gas Recommended Assessment and Documentation for

Service Life Extension of Facilities, (2012) [5] provides good guidance on the processes, resources and methodologies used in the ALE approach to find the "as is" condition and re-qualification for life extension and how to implement and document. Safety critical elements (SCEs) such as wells, subsea jacket structures, pipelines, risers, mechanical equipment etc. are to be qualified for the continuous operations and asset life extension. Quantitative and qualitative assessments are generally employed for equipment where known degradation mechanisms are prevalent and where quantitative models exist to calculate degradation, remaining margins and prediction of remaining service life. Quantitative analysis including

on the facilities that are not to be breached. They include:

Maintenance Management of Aging Oil and Gas Facilities

DOI: http://dx.doi.org/10.5772/intechopen.82841

• Structural integrity;

• Process integrity;

• Fire and explosion;

• Mechanical integrity;

• Marine integrity;

• Pipelines;

• Corrosion;

• Human factors.

• Subsea systems

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• Life-saving equipment

• Cranes and lifting equipment

• Telecommunication facilities

impact of the time and aging processes (Figure 7).

• Electrical, control and instrumentation;
