1. Introduction

Oil and gas facilities range from both upstream and downstream assets to include offshore structures, onshore tank farm facilities. Offshore structures may include the typical fixed offshore structures, monopods, guyed wire caissons to the more complex deep water assets including Floating Production and Storage Offloading (FPSO), Mobile Offshore Production Unit (MOPU), Tension Leg Platform (TLP) and semi-submersible structures (Figures 1 and 2).

Extending operation facilities beyond design life presents safety risks, business risks and operational challenges to the oil and gas industry. These risks affect significant business decisions and need to be quantified and managed as we strive for continuous operations of aging assets. Aging assets and equipment present increased challenges in maintaining equipment integrity and hence, will need to be managed accordingly. These could be because of a cumulative degradation and risks over time, which includes:


Assets are required to predict and understand the effects of deterioration, or changing conditions associated with life extension and be prepared to intervene to ensure that this demand can be met without adverse effect on asset integrity and safety. Asset life extension (ALE) for a given design life expiry, refers to a condition whereby an asset is approaching its intended design life. The main aging factors that need to be considered when developing an ALE program are material degradation (Figure 3), obsolescence and organizational issues. This is provided within Figure 4. The status of the known degradation mechanisms applicable for safety barriers should be evaluated and documented. The basis for acceptance of deviations and management of change (MoC) is reviewed in as a justification for the new mode and timeframe for continuous operations. The engineering evaluations of all changes and eventually mitigation measures against all operating risks must be documented. OGPs must review, evaluate assess all damage mechanisms or defects that may impact the facilities or individual operating systems for the life extension period. This is generally applicable to damage or defects where a temporary MoC has been accepted due to a limited period of use and this period has since been changed as a result of ALE considerations. The OGP is then required to re-assess the basis for acceptance to verify that this is still valid for the new period. Components or systems with a high consequence of failure, which are not available for inspection must be identified, evaluated, analyzed, and qualified for life extension. It is required that OGPs evaluate the consequence in case of failure, monitors

Maintenance Management of Aging Oil and Gas Facilities

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

Figure 3.

Figure 4.

63

Aging management [4].

Degradation of offshore structural component [3].


Figure 1. Typical offshore structures [1].

Figure 2. Typical onshore tank farm facility [2].

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

• 'Slow burn' degradation mechanisms;

degraded conditions as being the new normal);

• Changes to engineering codes and standards;

tracers, off spec water injection, etc.).

spares, etc.;

Maintenance Management

time;

industry;

Figure 1.

Figure 2.

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Typical offshore structures [1].

Typical onshore tank farm facility [2].

• Obsolescence of equipment leading to potential lack of spares, high cost of

• Normalization of deviance associated with human factors (i.e. accepting

• Lack of data trending to forecast future risks to safety and business continuity;

• Failure to record the accurate status of safety critical elements (SCE) over

• Loss of technical competence (qualifications + training + experience) in the

• Introduction of foreign materials into the production systems (e.g. Chemicals for Enhanced Oil Recovery (EOR), downhole sand consolidation, chemical

Assets are required to predict and understand the effects of deterioration, or changing conditions associated with life extension and be prepared to intervene to ensure that this demand can be met without adverse effect on asset integrity and safety. Asset life extension (ALE) for a given design life expiry, refers to a condition whereby an asset is approaching its intended design life. The main aging factors that need to be considered when developing an ALE program are material degradation (Figure 3), obsolescence and organizational issues. This is provided within Figure 4.

The status of the known degradation mechanisms applicable for safety barriers should be evaluated and documented. The basis for acceptance of deviations and management of change (MoC) is reviewed in as a justification for the new mode and timeframe for continuous operations. The engineering evaluations of all changes and eventually mitigation measures against all operating risks must be documented. OGPs must review, evaluate assess all damage mechanisms or defects that may impact the facilities or individual operating systems for the life extension period. This is generally applicable to damage or defects where a temporary MoC has been accepted due to a limited period of use and this period has since been changed as a result of ALE considerations. The OGP is then required to re-assess the basis for acceptance to verify that this is still valid for the new period. Components or systems with a high consequence of failure, which are not available for inspection must be identified, evaluated, analyzed, and qualified for life extension. It is required that OGPs evaluate the consequence in case of failure, monitors

Figure 3. Degradation of offshore structural component [3].

Figure 4. Aging management [4].

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

the different parts of the facilities are planned to be used. An ALE framework outlining the main tasks as a six (6) step process is proposed and provided below on

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.

Figure 5.

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Asset life extension process [6].

3.1 Data and information

Maintenance Management of Aging Oil and Gas Facilities

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

A case study is provided within Section 11, to demonstrate a simple application of the ALE framework and possible outcomes.
