3.2 Gap assessment

Gap assessment is the second stage of an ALE process. Identifying gaps can be broken down to several steps, which includes:


The gap assessment shall focus on the barrier functions and the factors that influence the barrier elements. This includes technical, organizational and operational elements. The gap assessment and recommendations are performed based on the major inspection findings, root cause failure analysis reports, modification implemented on the equipment, bad actor list, history of incidents, maintenance report, overhaul findings, reliability data, operating and maintenance philosophy and any condition monitoring recommendation. Any life extension recommendation must take the future technical condition, operating parameters and mode of operation into consideration. The assessment should also include review of the forecasted production profile, exploiting synergy with other related equipment such that key assets and system infrastructure can be rationalized, optimized or expanded. A process for the identification and correction of gaps is provided within Figure 6.

Figure 6. Process for identification and correction of gaps [5].

Maintenance Management of Aging Oil and Gas Facilities DOI: http://dx.doi.org/10.5772/intechopen.82841

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


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

Gap assessment is the second stage of an ALE process. Identifying gaps can be

The gap assessment shall focus on the barrier functions and the factors that influence the barrier elements. This includes technical, organizational and operational elements. The gap assessment and recommendations are performed based on the major inspection findings, root cause failure analysis reports, modification implemented on the equipment, bad actor list, history of incidents, maintenance report, overhaul findings, reliability data, operating and maintenance philosophy and any condition monitoring recommendation. Any life extension recommendation must take the future technical condition, operating parameters and mode of operation into consideration. The assessment should also include review of the forecasted production profile, exploiting synergy with other related equipment such that key assets and system infrastructure can be rationalized, optimized or expanded. A process for the identification and correction of gaps is provided within

program.

Figure 6.

Figure 6.

66

Process for identification and correction of gaps [5].

3.2 Gap assessment

Maintenance Management

broken down to several steps, which includes:

• Identify hazards and critical barriers.

• Check integrity and functionality of barriers.

• Review historic performance of barriers.

• Review current state of maintenance and gaps.

• Assess current performance of barrier against intent.


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

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

Figure 7.

Recommended life extension assessments of barriers [5].

probability of failure (PoF) is generally employed for structures, pipelines, position mooring, and flexible or steel catenary risers etc. and requires string technical expertise and often specialist software packages. Qualitative assessments is also possible but must be supported by effective data management and operating historical data to make good engineering assessments.

previously), are used. After assessing the potential outcome, the likelihood on the vertical axis is determined on the basis of historical evidence or experience that such consequences have materialized within the industry, the entity or a smaller unit

Effective inspection and maintenance are important in ensuring asset integrity

and reliability. In developing the maintenance management systems an initial review is required determine status and how the aging processes is covered in the existing maintenance program. The review is to evaluate the need for updating the integrity, reliability, vulnerability and consequence analysis for continuous operations in the future. Experience and knowledge from documented failures and lessons learnt shall also be part of the evaluation and be used to improve the maintenance management system. In principle, the maintenance management system should be within a computerized database with detailed history of the operating, design, assessment, inspection and maintenance records accessible to all

A review of the current emergency response systems must be performed, including an evaluation of how operational changes and new requirements will be met in the period of life extension. If there is a change in operating philosophy, HSE Case shall be revisited. OGPs are to evaluate any likely operational or organizational changes to the facilities that will affect the emergency preparedness and response

Human factors area comprises methods and knowledge which can be used to assess and improve the interaction between people, technology and organization to realize efficient and safe operations. The factors should include organizational

(Figure 8).

Figure 8.

key personnel.

systems.

69

4. Emergency preparedness

5. Organizational and human factors

3.4 Maintenance management system

Typical risk matrix used by oil and gas producers (OGPs).

Maintenance Management of Aging Oil and Gas Facilities

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