The Importance of SIMS in Structural Integrity Review and Life Extension Requirement for Existing Fixed Offshore Structure

2016 ◽  
Author(s):  
Alex E. Kajuputra ◽  
Wong Bak Shiiun ◽  
M. Akmal Shamsuddin
Keyword(s):  
Structural Integrity ◽  
Life Extension ◽  
Offshore Structure

Development of a Micro-Habitat Hyperbaric Welding System

2021 ◽  
Author(s):  
Earl Lee Toups ◽  
Russell James Morrison ◽  
Russell John Harper
Keyword(s):  
North Sea ◽  
Design Thinking ◽  
Structural Integrity ◽  
Fatigue Cracks ◽  
Fatigue Cracking ◽  
Life Extension ◽  
Acceptance Testing ◽  
Offshore Structure ◽  
The North ◽  
Welding System

Abstract The maturation of North Sea platform jackets coupled with high fatigue stresses, fabrication defects, extensive usage, and low-redundancy design eventually result in fatigue cracking. The high sea states in the North Sea further exacerbate the problem. If not closely monitored, fatigue cracks can propagate into and around the circumference of a brace relatively quickly—ultimately leading to brace severance. When confronted with a loss of structural integrity, operators have two options: conduct expensive subsea repairs or decommission the asset. Realising a market gap, DCN Diving has explored alternate repair strategies, leading to the development of the DCN-patent pending µ-Habitat welding system. The µ-Habitat makes it possible to respond quicker, execute subsea repairs faster and guarantee quality at a fraction of the cost of bespoke or modular habitats. Through size reduction, it is possible to reduce the fabrication, production, and handling costs of µ-Habitat. Furthermore, the smaller footprint reduces installation time while simplifying sealing and de-watering offshore, saving time and money. Using a combination of product development facilitators and process improvement methodologies, such as AGILE, SCRUM, and design thinking, reduces the preparation time, making the system incredibly responsive yet flexible. Additionally, using an experienced and dedicated project team in combination with standardised products further minimises the response time to execute a repair. A dry environment, pre-heating, in-process cleaning/grinding, and unrestricted access are fundamental to ensuring high-quality welds. In addition, prototyping, extensive function testing, and mock-ups validate the habitat design before commissioning via factory acceptance testing and mobilisation to guarantee the failsafe performance of the µ-Habitat offshore. The µ-Habitat can play a crucial role in the overall life extension strategy for any offshore structure, ultimately minimising cost, risk and production downtime associated with future subsea repairs.

Ultrasound and Nonlinear Resonant Testing of Nuclear Reactor Internals Bolts

2011 ◽  
Author(s):  
S. W. Glass ◽  
B. Thigpen ◽  
J. Renshaw
Keyword(s):  
Phased Array ◽  
Nuclear Reactor ◽  
Structural Integrity ◽  
Cost Effective ◽  
Life Extension ◽  
Safe Operation ◽  
Plant Life ◽  
Nuclear Plants ◽  
Bolt Failure ◽  
Reactor Internals

As many nuclear plants approach the end of their initial 40 year license period, inspection or replacement of their reactor internals bolts must be considered. This is consistent with the Materials Reliability Program (MRP 227/228) guideline for plant life extension [1,2]. Assurance of the internals structural integrity is essential for continued safe operation of these plants. If there is no suspicion or indication of bolt failure, simple inspection is normally more cost-effective than replacement. Inspection vendors have inspected thousands of internals bolts with conventional and Phased Array UT but different head configurations and bolt capture mechanisms mandate specific qualifications for each bolt type. In some cases, complex bolt and head geometries coupled with counter-bore and locking bar interferences render classical UT inspections difficult or impossible. A range of solutions to inspect reactor internals including these difficult-to-inspect-by-conventional-UT baffle bolts has been developed by several vendors [3]. This presentation references developments to make bolt inspection a relatively quick and easy task through adaptations to the SUSI submarine inspection platform, the extensive UT qualification work suitable for conventional UT plus more recent advanced nonlinear resonant techniques to distinguish between flawed or loose, vs. acceptable bolts where conventional UT cannot be applied. Initial evaluations show that these advanced techniques may have the ability to reliably detect smaller flaws than previously possible with conventional techniques as well as provide information on bolt tightness.

Parametric Investigation on the Effect Factors for Liquid Droplet Impingement Erosion

2011 ◽  
Author(s):  
Rui Li ◽  
Hisashi Ninokata ◽  
Michitsugu Mori
Keyword(s):  
Power Plants ◽  
Erosion Rate ◽  
Structural Integrity ◽  
Volume Fraction ◽  
Liquid Droplet ◽  
Droplet Velocity ◽  
Life Extension ◽  
Droplet Impingement ◽  
Pipe Surface ◽  
Bent Pipe

Liquid droplet impingement (LDI) erosion could be regarded to be one of the major causes of unexpected troubles occasionally occurred in the inner bent pipe surface. Evaluating the LDI erosion is an important topic of the thermal hydraulics and structural integrity in aging and life extension for nuclear power plants safety. In order to investigate the effect of various parameters, such as droplet diameter, droplet velocity and injected droplet number, on the erosion rate induced by LDI, droplet impingement under different conditions are conducted numerically by a two-phase computational approach. Considering the carrier turbulence kinetic energy attenuation due to the involved droplets, numerical simulations have been performed by using two-way vapor-droplet coupled system. This computational fluid model is built up by incompressible Reynolds Averaged Navier-Stoke equations using standard k-ε model and the SIMPLE algorithm, and the numerical droplet model adopts the Lagrangian approach, a general LDI erosion prediction procedure for bent pipe geometry has been performed to supplement an available CFD code. A correlation for the erosion rate in terms of droplet velocity, diameter and volume fraction is purposed for the engineers’ maintenance reference. Based on our computational results, comparison with an available accident data was made to prove that our methodology could be an appropriate way to simulate and predict the bent pipe wall thinning phenomena.

New Standard for Assessment of Structural Integrity for Existing Load-Bearing Structures-Norsok N-006

2009 ◽  
Author(s):  
Gunnar Solland ◽  
Inge Lotsberg ◽  
Lars G. Bjo̸rheim ◽  
Gerhard Ersdal ◽  
Vidar-Andre´ Gjerstad ◽  
...  
Keyword(s):  
Structural Integrity ◽  
Regulatory System ◽  
Life Extension ◽  
Design Standards ◽  
Load Bearing ◽  
Fatigue Design ◽  
Design Life ◽  
Advanced Analysis ◽  
The Cost ◽  
Existing Structure

An increasing number of platforms in the Norwegian continental shelf are reaching their design life. For various reasons these platforms will require an assessment of their structural integrity. When performing these assessments the engineer is faced with tasks where little guidance is found in design standards, for several reasons. The two most important being: 1) The analyses that is performed in a typical assessment of existing structure is often applying very advanced techniques and methodology that seldom is used in design of new structures, as the cost of doing advanced analysis is relatively low compared to replacement of an existing structure, but relatively high compared to moderate additions of e.g. steel in the design of a new structure. 2) Design standards are based on theories, methods and experience for structures in a given design life (e.g. fatigue design and corrosion protection design). When this design life is extended, sound methods for ensuring that the structures are still sufficient safe is needed. Such methods will normally be “condition based design”, where inspection, maintenance and repairs are included in the assessment in integrated way. Such methods are not given in normal design standards. For these reasons a new NORSOK standard is developed that gives recommendation on how to deal with the specific aspects that engineers meet when performing assessments of structures in general, but also specifically for assessment for life extension. The standard is named “Standard for Assessment of Structural Integrity for Existing Load-bearing Structures” and is issued as a NORSOK standard and given the number N-006 [1]. The topics that are covered in the standard include: Shut down and unmanning criteria for platforms not meeting ordinary requirements, specific issues for determination of ultimate capacities by use of non-linear methods, cyclic capacity checks, fatigue life extension, requirements to in-service inspection etc. The paper describes the background and the content of the new standard and it presents examples of recommendations given. The role of the new standard in the Norwegian regulatory system is shown.

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.

Use of ultrasonic models in the design and validation of new NDE techniques

1986 ◽  
Vol 320 (1554) ◽  
pp. 329-340 ◽  
Keyword(s):  
Fracture Mechanics ◽  
Elastic Wave ◽  
Structural Integrity ◽  
Life Extension ◽  
Experimental Demonstration ◽  
Structural Components ◽  
Model Calculations ◽  
Model Predictions ◽  
The Cost ◽  
Theoretical Scattering

In implementing fracture mechanics based techniques for the design and life extension of structural components, it is necessary to establish the reliability with which various flaw sizes and types can be detected and characterized. Traditionally, this has been accomplished through extensive experimental demonstration programmes. This paper discusses present efforts to use model predictions to reduce the required amount of experimentation, and hence the cost, of such programmes. Formalisms whereby the extensive elastic-wave theoretical scattering effort of the last decade can be applied to practical problems are first reviewed. This is followed by several specific examples which have occurred in the nuclear and aerospace industries. The paper concludes with the identification of some important remaining theoretical problems and a discussion of possible strategies for future implementation of model calculations as tools in structural integrity programmes.

Developing the Structural Integrity Management System for Ageing Fixed Offshore Oil Platforms in Indonesia

2017 ◽  
Vol 862 ◽  
pp. 265-270
Author(s):  
Raditya Danu Riyanto ◽  
Murdjito
Keyword(s):  
Management System ◽  
Structural Integrity ◽  
Offshore Structures ◽  
Offshore Platforms ◽  
Offshore Structure ◽  
Element Analysis ◽  
East Kalimantan ◽  
Ranking Criteria ◽  
Life Years ◽  
Integrity Management

Offshore structure, particularly fixed offshore structures, should be kept in the performance for the fit-for-purpose condition during their operating lifetime. For fixed offshore structures that exceed their designated life years, the proper Structural Integrity Management System (SIMS) should be developed and applied. Despite the fixed offshore platforms have their service life, there are still platforms that continue to operate exceeding their service lifetime. These ageing platforms should be taken care thoroughly to avoid the consequences that could take casualties. This paper will propose the proper initiation of SIMS development for ageing fixed offshore platforms in Indonesia, by taking an example at Bekapai Field Platforms in East Kalimantan. Using HAZID technique and several ranking criteria, the platforms are assessed and ranked. Platforms that categorized in critical condition are grouped based on similarities in geometry and function. The highest rank is analyzed in computer Finite Element Analysis (FEA) Software with modification based on latest inspection result. This method is proven to be a proper method to be used as a maintenance program for ageing fixed offshore platforms in Indonesia.

Procedures on Fracture Toughness Estimation Safety Assessment and Life Extension for In-Service High Pressure Vessels

2004 ◽  
Author(s):  
Guohua Chen ◽  
Bonuan Chen
Keyword(s):  
Fracture Toughness ◽  
High Pressure ◽  
Safety Assessment ◽  
Structural Integrity ◽  
Pressure Vessels ◽  
Life Extension ◽  
Temper Brittleness ◽  
Integrity Assessment ◽  
Treatment Processes ◽  
Material Fracture

Based on the typical in-service high pressure vessels made of PCrNi3MoVA for producing synthetic crystal, a systematic technology of material fracture toughness estimation, structural integrity assessment, and life extension is carried out for the in-service equipment with the following aspects: macroscopically and microscopically analyzing, the tests including KIC, AKV, FATT (50%), the predicting method of fracture, system safety assessment, and the life extension technology. Some practical conclusions can be obtained from the test and analysis as follows: The main failure factors for this kind of high pressure vessels include heat treatment processes, temper brittleness, and stress corrosion; It is found that the value of FATT (50%) increased very significantly; The comparison between the test results and the predicted results of the value of KIC is also performed, and it is shown that the value of KIC of in-service equipment can be estimated by the formula presented by Barsom-Rolfe or in API 579 with the value of AKV, The test temperature is recommended at least to reach 25 C (or room temperature) for the repaired vessels; The life extension technologies are put forward for this kind of in-service super-high pressure vessels.

Implementation of Advanced Offshore Structure Integrity Management based on API RP2SIM in Medco E&P Offshore

2020 ◽  
Author(s):  
E. Islami
Keyword(s):  
Structural Integrity ◽  
Good Practice ◽  
General Information ◽  
Offshore Structure ◽  
Potential Cost ◽  
Integrity Management ◽  
Advanced Analysis ◽  
Inspection Data ◽  
Data Update ◽  
Reserve Strength

The structural integrity management (SIM) is important for the safe operation and maintenance of offshore fixed platform installation in accordance with the objectives set out in the Asset & Operating Integrity Philosophy. A Structural Integrity Program as part of the SIM is required as an ongoing process to ensure fitness-for-purpose of an offshore structure. Medco E&P developed the SIM system based on API RP2SIM in year of 2014 and has been successfully implementing it for the last 6 years. Based on this system, the interval of underwater inspection has been lengthened from every 2 years (time based inspection) into 4-10 years interval depend on the platform criticality. The potential cost saving of 70% is obtained as a result of implementation the underwater inspection for 10 years period based on inspection practices recommended in API RP 2SIM. The implementation of SIM process based on API RP 2SIM includes managing data, evaluation, strategy and program, the continuous improvement efforts and lesson learned. Medco E&P has implemented an advanced SIM program by determining the underwater inspection program based on risk based underwater inspection and consistently revisit and review the methodology; conduct the advanced analysis for reserve strength ratio; manage platform requalification; follow-up underwater inspection and repair; develop the integrated database system and the platform healthiness dashboard. The integrated database SIM System established a good practice for managing data record, data trending and data update since the system itself contains the platform of general information such as; the inspection data, inspection plan, structural analysis record, change record, reference document as well as the reporting tools. This dashboard is a combined status of initiatives, programs, implementation and evaluations that enables the integrity status can be accessed by management or other groups in the Company to promote effective communication and basis for decision making.

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