Development of Key Performance Indicators for Offshore Structural Integrity

2008 ◽  
Author(s):  
J. V. Sharp ◽  
G. Ersdal ◽  
D. Galbraith
Keyword(s):  
Performance Indicators ◽  
Structural Integrity ◽  
Performance Standards ◽  
Key Performance Indicators ◽  
Offshore Structures ◽  
Life Extension ◽  
Offshore Installations ◽  
Incident Rate ◽  
Safety Systems ◽  
Incident Rates

Key performance indicators (KPIs) are widely used to assess performance against targets, whether these be technical, environmental or financial. Offshore KPIs are used by both duty holders and regulators to assess the reliability of equipment and systems, often they relate to safety systems and the regulator’s interest relates to such systems. The most obvious KPIs include number of fatalities, fatal accident rate, lost time injury frequency and total recordable incident rate, as well as hydrocarbon release incident rates associated with maintaining safety. Many of the “non-headline” KPIs relate to systems that could be critical in the event of an accident and these are of great importance. However KPIs have not yet been developed for the performance of the offshore structural system. Performance standards are a requirement of current UK offshore legislation, although these again are more normally associated with fire and explosion. Since many offshore installations are now in the ageing phase performance measures are increasingly important. This paper described the background to developing KPIs for offshore structures, relating to aspects which are important for both safety and asset integrity. This has been achieved based on a hazard approach, which includes extreme weather, fatigue, corrosion and accidental damage. KPI’s need to be measurable and this aspect has been incorporated in their development. It is proposed that these KPIs will have significant use in providing a basis for measuring structural performance, particularly for ageing installations where a case for life extension needs to be made.

Fatigue Life Extension of Offshore Structures by Ultrasonic Peening

2011 ◽  
Author(s):  
Luis Lopez Martinez
Keyword(s):  
Fatigue Life ◽  
Service Life ◽  
Fatigue Resistance ◽  
Structural Integrity ◽  
High Stress ◽  
Offshore Structures ◽  
Life Extension ◽  
Original Design ◽  
Ultrasonic Peening ◽  
Offshore Installations

The service life of offshore installations is limited by its structural integrity. Furthermore the structural integrity is mainly governed by the fatigue resistance of critical welded details. In a FPSO installation these details are among others pallet stools weld joints to deck structure and bulkheads/web frames weld connections to longitudinal in ballast tanks. ultrasonic peening can improve the fatigue resistance of welded joints. Fatigue test results shows an increase of four times for high stress ranges and up to ten times for high cycle fatigue. For specimens which have already consumed half of their fatigue life the treatment resets the clock to zero, as a minimum value. Consequently ultrasonic peening treatment was applied to several offshore installations on fatigue sensitive weld connections with the objective to extend the service life of the these. Finite Element Analysis carried out by classification societies for these offshore structures demonstrated critical fatigue lives for several weld connections. These weld connections were then treated by ultrasonic peening with the objective to extend their fatigue lives and by doing that reach the targeted service life for the installation. The successful application of the ultrasonic peening treatment was a pioneering work which involved several partners. A pilot project on a FPSO started in 2005 and the treated critical weld connections are still intact and show not sign of crack initiation despite the fact the calculations then showed shorter fatigue lives than the life span already consumed. As a result the same ultrasonic peening procedure has been proposed to be applied for other fatigue sensitive locations on the installation. Offshore installations around the world are reaching their original design life. Most of the operators chose to extend the service life of their assets rather than scrape them and build new. The reasons for that are: improved oil recovering techniques, time required to get a new build installation on site, environment concerns, wiser management of energy and resources among others. Therefore the Life Extension of Offshore Installations is a subject of current interest for the upstream industry.

State of Art in Life Extension of Existing Offshore Structures

2012 ◽  
Author(s):  
Abe Nezamian ◽  
Robert J. Nicolson ◽  
Dorel Iosif
Keyword(s):  
Structural Integrity ◽  
Oil And Gas ◽  
Offshore Structures ◽  
Life Extension ◽  
Operational Environment ◽  
Original Design ◽  
Safety Level ◽  
Operational Conditions ◽  
Offshore Installations ◽  
State Of Art

A large number of the old oil and gas facilities have reached or exceeded their initial design life. With a continued requirement to produce oil or gas, either from the original fields or as a base for neighbouring subsea completions, many of these respective offshore installations are likely to remain operational for a period of time in the foreseeable future. The ageing offshore infrastructure presents a constant and growing challenge. Ageing is characterised by deterioration, change in operational conditions or accidental damages which, in the severe operational environment offshore, can be significant with serious consequences for installation integrity if not managed adequately and efficiently. In order to ensure technical and operational integrity of these ageing facilities, the fitness for service of these offshore structures should be maintained. The maintenance of structural integrity is a significant consideration in the safety management and life extension of offshore installations. Detailed integrity assessments are needed to demonstrate that there is sufficient technical, operational and organisational integrity to continue safe operation throughout a life extension. Information on history, characteristic data, condition data and inspection results are required to assess the current state and to predict the future state of the facility and the possible life extension. This paper presents state of art practices in life extension of existing offshore structures and an overview of various aspects of ageing related to offshore facilities, represented risk to the integrity of a facility and the required procedures and re assessment criteria for deciding on life extension. This paper also provides an overall view in the structural requirements, justifications and calibrations of the original design for the life extension to maintain the safety level by means of a maintenance and inspection programs balancing the ageing mechanisms and improving the reliability of assessment results.

Hull Structure Integrity Management in Floating Structures–FSO Puteri Dulang Case

2014 ◽  
Vol 69 (7) ◽  
Author(s):  
Ajith Kumar Thankappan ◽  
M. Fazli B. M. Yusof
Keyword(s):  
Fatigue Life ◽  
Structural Integrity ◽  
Structural Response ◽  
Offshore Structures ◽  
Design Phase ◽  
Floating Structures ◽  
Offshore Installations ◽  
Hull Structure ◽  
Integrity Management ◽  
New Buildings

This paper highlights the key differences in practices employed in managing hull structure integrity of permanently moored floating offshore structures as against sailing vessels which are subject to periodic dry docking. During the design phase, the structural integrity management over the life of a sailing vessel is primarily taken into account by means of Class prescribed Nominal Design Corrosion Values which are added to minimum scantling requirements calculated based on strength and fatigue criteria. In contrast, for permanently moored offshore installations like FPSOs, FSOs etc. the hull structure integrity over the entire design life of the asset is a key design consideration both for new buildings and conversions. Analytic methods and tools (primarily those developed by Class Societies) are available to evaluate the strength requirements (based on yielding, buckling and ultimate strength criteria) and fatigue life of the hull structure. Typically three levels of analysis with increasing degree of complexity and analysis time are used to predict the structural response and fatigue life of the Hull during design phase. The degree of detailed analysis required needs to be determined in light of the expected optimization in terms of savings in scantlings for new building or for steel renewal requirements in case of conversions.

An Oil Field Structural Integrity Assessment for Re-Qualification and Life Extension

2013 ◽  
Author(s):  
Abe Nezamian ◽  
Joshua Altmann
Keyword(s):  
Weight Control ◽  
Structural Integrity ◽  
Offshore Structures ◽  
Oil Field ◽  
Assessment Process ◽  
Performance Criteria ◽  
Life Extension ◽  
Original Design ◽  
Integrity Assessment ◽  
Design Life

The ageing of offshore infrastructure presents a constant and growing challenge for operators. Ageing is characterised by deterioration, change in operational conditions or accidental damages which, in the severe operational environment offshore, can be significant with serious consequences for installation integrity if not managed adequately and efficiently. An oil field consisting of twelve well head platforms, a living quarter platform (XQ), a flare platform (XFP) and a processing platform (XPA) are the focus of this paper, providing an overview of the integrity assessment process. In order to ensure technical and operational integrity of these ageing facilities, the fitness for service of these offshore structures needs to be maintained. Assessments of the structural integrity of thirteen identified platforms under existing conditions were undertaken as these platforms are either nearing the end of their design life or have exceeded more than 50% of their design life. Information on history, characteristic data, condition data and inspection results were collected to assess the current state and to predict the future state of the facility for possible life extension. The information included but was not limited to as built data, brown fields modifications, additional risers and clamp-on conductors and incorporation of subsea and topside inspection findings. In-service integrity assessments, pushover analyses, corrosion control and cathodic protection assessments and weight control reports were completed to evaluate the integrity of these facilities for requalification to 2019 and life extension to 2030. The analytical models and calculations were updated based on the most recent inspection results and weight control reports. A requalification and life extension report was prepared for each platform to outline the performance criteria acceptance to achieve requalification until 2019 and life extension until 2030. This paper documents the methodology to assess the platform structural integrity in order to evaluate platform integrity for the remaining and extended design life. An overview of various aspects of ageing related to these offshore facilities, representing risk to the integrity, the required procedures and re assessment criteria for deciding on life extension of these facilities is presented. This paper also provides an overall view of the structural requirements, justifications and calibrations of the original design for the life extension to maintain the safety level by means of maintenance and inspection programs balancing the ageing mechanisms and improving the reliability of assessment results.

Criticality Rating of Ageing Fixed Offshore Structures

2011 ◽  
Author(s):  
S. Gupta ◽  
D. Sanderson ◽  
A. Stacey
Keyword(s):  
Structural Integrity ◽  
Offshore Structures ◽  
Structural Failure ◽  
Offshore Installations ◽  
Integrity Management

The effective structural integrity management of the ever-increasing population of ageing offshore installations on the UKCS requires the identification of key parameters which provide a measure of the criticality of installations to structural failure, thus enabling priorities to be set. This paper describes a model for the evaluation of the criticality rating of fixed offshore installations.

Reliability and (Re)Assessment of Fixed Steel Structures

2011 ◽  
Author(s):  
Mike Efthymiou ◽  
Jan Willem van de Graaf
Keyword(s):  
Structural Reliability ◽  
Structural Integrity ◽  
Steel Structures ◽  
Performance Standards ◽  
Offshore Structures ◽  
Design Standards ◽  
Component Strength ◽  
Post Buckling ◽  
Exposure Levels ◽  
Joint Occurrence

This paper reviews the structural integrity and reliability of fixed steel offshore structures with a focus on improved models and incorporation of these models in design standards. Technical achievements in four key areas are reviewed which, when combined, resulted in a step improvement in the calculation of structural reliability. The first area is the extreme environmental loading on an offshore platform; the second area is the joint occurrence of waves, winds and currents, i.e. accounting for the fact that these do not, in general, peak at the same time and do not act in the same direction. The third area is the estimation of the ultimate strength of a fixed steel platform, accounting for component strength, including the buckling and post-buckling behaviour and the uncertainty in system strength. The fourth and final area is the integration of the above models to estimate the probability of failure. The historical performance of platforms and the improvements in successive editions of API RP 2A are reviewed; reliability targets appropriate for different exposure levels and corresponding performance standards are developed, aimed at harmonizing design practices worldwide. A differentiation is recommended between permanently manned L-1 installations and manned-evacuated L-1 installations in the Gulf of Mexico; this is because the consequences of failure are considerably different.

Industry Practices for the Management of Ageing Assets Relevant to Offshore Installations

2011 ◽  
Author(s):  
John V. Sharp ◽  
John B. Wintle ◽  
Carol Johnston ◽  
Alex Stacey
Keyword(s):  
Offshore Structures ◽  
Life Extension ◽  
Offshore Installations ◽  
Process Plant ◽  
The Uk ◽  
Industry Sectors ◽  
Consistent Approach

This paper describes the results of a survey for the UK regulator of industrial practices for the management of ageing assets and life extension that are relevant to offshore structures. The industry sectors surveyed covered aircraft, process plant, nuclear installations, bridges and ships and tankers, which like the offshore sector, all have mature and/or degrading assets important to safety. The conclusion is drawn that although the offshore sector is aware of the need to give more attention to the management of ageing and life extension, it would benefit from a more integrated and consistent approach that is present in other sectors. Examples of where the offshore sector can benefit from practices in other sectors are described.

Use of Capability Maturity Modelling to Ensure Ageing and Life Extension are Adequately Considered in Structural Integrity Management

2011 ◽  
Author(s):  
J. V. Sharp ◽  
G. Ersdal ◽  
D. Galbraith
Keyword(s):  
Continental Shelf ◽  
Structural Integrity ◽  
Life Extension ◽  
Capability Maturity ◽  
Offshore Installations ◽  
Ageing Processes ◽  
Integrity Management ◽  
Norwegian Continental Shelf

An increasing number of offshore installations are in the life extension stage of life, with ageing processes needing to be taken into account. This is particularly important for structural integrity. Capability Maturity Modelling enables the levels of maturity in processes associated with the management of ageing to be identified and improved if required. The paper describes the model and how it has been used for assessing the management of structural integrity for installations on the Norwegian Continental Shelf.

scholarly journals Principal Leadership Styles and Teacher Job Performance: Viewpoint of Middle Management

2020 ◽  
Vol 12 (8) ◽  
pp. 3390
Author(s):  
Atif Saleem ◽  
Sarfraz Aslam ◽  
Hong-biao Yin ◽  
Congman Rao
Keyword(s):  
Job Performance ◽  
Leadership Styles ◽  
Principal Leadership ◽  
Performance Indicators ◽  
Structural Equation ◽  
Middle Management ◽  
Performance Standards ◽  
Key Performance Indicators ◽  
Equation Modeling ◽  
Principal Leadership Styles

Achievement-oriented leaders let their followers know their expectations. They regularly set clear goals with potential high-performance standards, they trust in the capabilities of their subordinates, and they encourage the continued performance improvement of their subordinates. This investigation studied the effects of private secondary school principals’ leadership styles on teachers’ job performance. Four leadership styles outlined in the path–goal theory and five key performance indicators (KPIs) of teacher job performance were chosen for the present research. Numerous prior studies have documented this subject. However, they reported on teacher job performance as a single unit. Therefore, a concerted effort was required to examine the effects of adopted principal leadership styles on each of the five key performance indicators of teacher job performance. A total of 253 middle management personnel took part in this empirical study. The correlation findings from the structural equation modeling revealed that the directive leadership style had a significant effect on teacher job performance in the studied schools, followed by the supportive and achievement-oriented leadership styles. Conversely, although participative leadership was identified as a significant predictor, it was not considered a promising predictor of teacher job performance. This research was conducted in a non-Western culture, where directive leadership is beneficial for encouraging teacher job performance; this claim is greatly supported by the available rigorous literature.

An ILI Based Program That Prevents Reoccurrence of Post ILI Failures Seen in Industry

2018 ◽  
Author(s):  
Terry Huang ◽  
Shahani Kariyawasam
Keyword(s):  
High Resolution ◽  
Performance Indicators ◽  
Rate Data ◽  
Years Of Experience ◽  
Appropriate Use ◽  
The Future ◽  
Incident Rate ◽  
Incident Rates ◽  
Program Changes

The pipeline industry has been using Inline Inspection (ILI) since the 1970s. High resolution tools have been available for inspecting corrosion from about the 1980s and related ILI-based programs have been evolving. In this study incident rate data from the last 30 to 40 years of experience was examined and trended. Corrosion related incident rates have reduced where ILI programs have been implemented. Significant changes in programs have shown related incident reductions or positive trends. Throughout this time there have been a few post-ILI incidents and by taking a closer look at these incidents and learning from the findings the ILI-based assessments and programs were further improved. In this study, all of the post-ILI corrosion related ruptures on the TransCanada system have been closely examined and trended. The effects of program changes and related changes to performance indicators have been examined. Some significant industry failures, where data is publicly available, have also been examined. These failures have been analyzed and trended to understand significant commonalities between these failures. Data was analyzed with the intention of learning from them and applying this learning to avoid similar failures in the future. By understanding the uncertainties, technology limitations, and limits of applicability as well as the types of programs used and where these have not identified probable failures practical solutions were derived. All of the failures have been examined (as allowed by the data available) to find approaches which would have proactively identified these events, so that similar events can be avoided in the future. ILI tools generate a wealth of information and appropriate use of this information has shown to be effective in managing pipelines. However, it is also important to understand the limitations of technologies, learn from the failures, and acknowledge uncertainties so that undesirable events can be avoided.

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