Prediction of Riser VIV With Staggered Buoyancy Elements

2016 ◽  
Author(s):  
Jie Wu ◽  
Malakonda Reddy Lekkala ◽  
Muk Chen Ong
Keyword(s):  
Fatigue Damage ◽  
Oil And Gas ◽  
Systems Design ◽  
Oil And Gas Industry ◽  
Flexible Cylinder ◽  
Natural Period ◽  
Gas Industry ◽  
Vibration Period ◽  
Offshore Industry ◽  
Different Diameters

Steel lazy-wave riser (SLWR) are attractive deepwater applications for offshore oil and gas industry. When subjected to current, both the buoyancy elements and the riser may experience Vortex Induced Vibrations (VIV). Such vibrations are the result of the periodic hydrodynamic forces that are induced by the interaction of slender bodies and external fluid flow. If the vibration period is close to the natural period of the system, it can lead to fast accumulation of fatigue damage to the risers and amplified drag loads. There is a competition between the vortex induced forces acting on the buoyancy element and the riser segment due to its different diameters. The interaction of the vortex shedding from the riser and the buoyancy element depends on many parameters, such as the arrangement of the buoyancy element, aspect ratio of the buoyancy element, etc. Shell Oil Company conducted VIV model tests with a straight flexible cylinder and staggered buoyancy elements corresponding to a buoyant section of a SLWR in MARINTEK in 2011. Five different buoyancy element configurations were tested. The test data has been extensively studied (Rao, et al 2015 and Jhingran, et al 2012). The interaction of the buoyancy elements and bare riser and its influence on the riser response (frequency, displacement and fatigue damage) have been investigated. Semi-empirical VIV prediction software, such as VIVANA [4], SHEAR7 [13] and VIVA [11] are most commonly used by the offshore industry in the riser systems design against VIV loads. However, these software are not purposely designed to account for the interaction of the bare riser section and the buoyancy elements. It is of great interest to evaluate the prediction accuracy. The purpose of this study is to benchmark the VIV prediction of riser with buoyancy elements using VIVANA. The prediction is compared with Shell model test results with focus on CF responses. Uncertainty and improvement of the prediction are also discussed.

Identifying Key Safety Culture Factors for the Offshore Industry

2021 ◽  
Author(s):  
Ning Lou ◽  
Ezra Wari ◽  
James Curry ◽  
Kevin McSweeney ◽  
Rick Curtis ◽  
...  
Keyword(s):  
Safety Culture ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Transportation Safety ◽  
Key Factors ◽  
Gas Industry ◽  
The Us ◽  
Offshore Industry ◽  
Offshore Oil And Gas ◽  
Offshore Oil

This research identifies key factors, or safety culture categories, that can be used to help describe the safety culture for the offshore oil and gas industry and develop a comprehensive offshore safety culture assessment toolkit for use by the US Gulf of Mexico (GoM) owners and operators. Detailed questionnaires from selected safety culture frameworks of different industries were collected and analyzed to identify important safety culture factors and key questions for assessment. Safety frameworks from different associations were investigated, including the Center for Offshore Safety (COS), Bureau of Safety and Environmental Enforcement (BSEE), and the National Transportation Safety Board (NTSB). The safety culture factors of each of these frameworks were generalized and analyzed. The frequency of the safety culture factors in each framework was analyzed to explore commonality. The literature review and analysis identified a list of common factors among safety culture frameworks.

Integration between RCM and RAM: a case study

2016 ◽  
Vol 33 (6) ◽  
pp. 852-880 ◽  
Author(s):  
Ilaria De Sanctis ◽  
Claudia Paciarotti ◽  
Oreste Di Giovine
Keyword(s):  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Practical Method ◽  
Environmental Safety ◽  
Gas Industry ◽  
Content Type ◽  
Availability Analysis ◽  
Plant Safety ◽  
Offshore Industry

Purpose – The purpose of this paper is to propose a practical method of performing maintenance in the offshore industry where engineers have to manage problems such as the high cost of operations, assuring an high availability of the plant, safety on board and environmental protection. Indeed an efficient maintenance method it is necessary in order to offer methods and criteria to select the rights maintenance strategies keeping in to account the environmental, safety and production constrains. Design/methodology/approach – The paper provides an overview of reliability centered maintenance (RCM) and reliability, availability, maintainability methodologies and an integration of the two methodologies in a particular case study in the oil and gas sector. Findings – This paper suggests an improvement of the well-established RCM methodology applicable to industries with high priority level. It is proposed an integration between a reliability analysis and an availability analysis and an application on the offshore oil and gas industry. Practical implications – The methodology provides an excellent tool that can be utilized in industries, where safety, regulations and the availability of the plant play a fundamental role. Originality/value – The proposed methodology provides a practical method for selecting the best maintenance strategy considering the equipment redundancy and sparing, the asset’s performance over long time scales, and the system uptime, downtime and slowdowns.

FLOATING PRODUCTION, STORAGE AND OFFLOADING FACILITIES—IMPACT OF THE NEW OIL TANKER CONSTRUCTION RULES

1994 ◽  
Vol 34 (1) ◽  
pp. 178
Author(s):  
Robin C. Gehling ◽  
Michael P. Lane ◽  
Robert M. Thornton
Keyword(s):  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Cooperative Effort ◽  
Gas Industry ◽  
Safety Certification ◽  
Offshore Industry ◽  
Offshore Oil And Gas ◽  
Oil Tankers ◽  
Offshore Oil ◽  
Double Hull

FPSOs are often converted from, and carry ship safety certification as, oil tankers. The two types of ship have been reasonably compatible until passage in early 1992 of new international requirements for tankers to be constructed or converted to double hull requirements and for existing vessels to be phased out when they have been in service for 25 to 30 years. Such requirements, which have become increasingly onerous since 1973, are based on the hazards involved in navigation of oil tankers and do not reflect the risks applying to FPSO operations.In cooperation with the Australian offshore industry, AMSA made a number of submissions to the International Maritime Organisation (IMO), seeking clarification on whether FPSOs should be subjected to the rules for oil tankers. To cover the possibility that it is confirmed that FPSOs should comply with the rules, the submission proposed modifications to those rules to reflect the FPSO operating environment.The submissions resulted in IMO deciding, in March 1993, that although FPSOs would continue to be treated as oil tankers, they would not be required to comply with the double hull requirements which could have necessitated their withdrawal from service upon reaching 30 years of age.Achievement of a successful conclusion to this project has involved a cooperative effort between AMSA and the offshore oil and gas industry.

Qualification of AM-Parts for The Offshore Industry

2021 ◽  
Author(s):  
Ole-Bjørn Ellingsen Moe ◽  
Bertrand Henri Benoit Maillon
Keyword(s):  
Additive Manufacturing ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Gas Industry ◽  
Industry Standards ◽  
Expert Advisory ◽  
Independent Expert ◽  
Recommended Practices ◽  
Offshore Industry ◽  
Wire Arc Additive Manufacturing

Abstract Use of additive manufacturing (AM) technology is quite mature in medicine and aerospace industries but adoption of the technology has been limited in the oil and gas industry. One of the reasons behind the slow adoption is the non-availability of industry standards and recommended practices. DNV aims to help the adoption of AM in the oil and gas industry by providing the needed industry standards and recommended practices. DNV is one of the largest classification societies in the world and provides classification, technical assurance, software and independent expert advisory services to the maritime, oil & gas and energy industries. DNV has been running several projects globally to help the industry qualify materials and products produced by additive manufacturing. DNV has been working since January 2018 together with main stakeholders in a joint Industry Project (JIP) to develop requirements necessary to introduce components made by AM for oil and gas and related applications. The outcome of the JIP was released to the industry in 2020; a standard that describes the qualification and quality assurance of AM parts. The AM technologies addressed in the standard are laser based powder bed fusion (PBF-LB) and wire arc additive manufacturing (WAAM). In this paper, the standard is presented, and a systematic way to qualify parts made by PBF-LB and WAAM technologies described. A case study, leading to a qualified part according to the standard will be presented. It has been led by Vallourec, a world leader in tubular solutions for the energy sectors. Vallourec embraced additive manufacturing a few years ago and is currently developing and offering WAAM components for various industries.

Best Available Techniques Applied to the Offshore Oil and Gas Industry

2014 ◽  
Vol 2014 (1) ◽  
pp. 388-399 ◽  
Author(s):  
Valentin Vandenbussche ◽  
Emma Karlstrøm Thylander ◽  
Daniel Millet
Keyword(s):  
Environmental Performance ◽  
Oil And Gas ◽  
Pollution Prevention ◽  
Oil And Gas Industry ◽  
Gas Industry ◽  
Site Specific ◽  
Best Available Techniques ◽  
Eu Directive ◽  
Offshore Industry ◽  
Offshore Oil

ABSTRACT Best Available Techniques (BAT) is a principle originally defined in the EU directive on Integrated Pollution Prevention and Control (IPPC). The overall ambition of the directive is to reduce emissions and impacts on the environment as a whole. The purpose of a BAT assessment is to identify the technique with the best environmental performance among all available techniques for a certain industrial application. Such assessment should also take into account technical and economic constraints. A wide variety of industries fall under the scope of the IPPC requirement for BAT in Europe. The BAT approach is more and more applied in countries outside of EU, and adopted by private organisations as a best practice. In the offshore Oil & Gas industry in Norway, for instance, the BAT approach is now applied to many systems, such as power generation, produced water management, VOC recovery, or, more recently, leak detection and remote sensing. The particularity of the site-specific constraints as well as a lifecycle perspective, typical of the offshore Oil & Gas industry, makes the application of the BAT approach challenging for this sector. Best Available Techniques for offshore applications are therefore site-specific, and require a case by case assessment. In addition, in countries such as Norway, there is no guideline or directive describing how to perform a BAT assessment, which hence needs interpretation and adjustment for each individual application. DNV has developed a methodology for BAT assessments specifically for the offshore industry. This methodology is based on a ranking of the environmental performance as well as technical feasibility, reliability and costs of available industrial concepts. The approach is applicable to various stages of offshore Oil & Gas projects. This paper will describe the BAT methodology for the offshore Oil & Gas industry, and give relevant examples of its application to various systems commonly found on offshore facilities. Challenges and future opportunities will also be presented and discussed.

Can the Caspian Sea Survive its Own Oil? Environmental Regulation of the Offshore Oil and Gas Industry in the Caspian Sea

2014 ◽  
Vol 29 (3) ◽  
pp. 415-456
Author(s):  
Elena Karataeva
Keyword(s):  
Caspian Sea ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
The Caspian Sea ◽  
Gas Industry ◽  
Industry Regulation ◽  
Regulatory Frameworks ◽  
Offshore Industry ◽  
Offshore Oil And Gas ◽  
Offshore Oil

This article critically examines the shortcomings of the offshore industry regulation in the Caspian Sea and proposes a framework to strengthen it. It considers the hydrocarbon industry and resources of the Caspian Sea region and analyses the extent and impacts of Caspian offshore oil and gas activities on its environment, reviews selected regional and global regulatory frameworks for the offshore oil and gas industry and their effectiveness, discusses existing shortcomings of the national and regional regulation of the Caspian offshore oil and gas industry, and provides suggestions on how it could be improved, drawing on the experience and regulatory formulations from other regions of the world.

Changes in labour and safety regulation offshore: the productivity implications

2016 ◽  
Vol 56 (2) ◽  
pp. 539
Author(s):  
Eleanor Taylor
Keyword(s):  
Trade Unions ◽  
Oil And Gas ◽  
Health And Safety ◽  
Oil And Gas Industry ◽  
Safety Regulation ◽  
Workplace Health ◽  
Gas Industry ◽  
Offshore Industry ◽  
Offshore Oil And Gas ◽  
The Impact

In recent years there have been ongoing tussles regarding the regulation of employment in the offshore oil and gas industry. Much of this conflict relates to the extent of union involvement in the industry, and the impact increased union activity may have on cost and productivity. This conflict has played out in the courts, legislature and the media. It is evidenced in the debate over the application of Australian migration laws to foreign workers offshore. This has involved lobbying by a number of organisations and Federal and High Court challenges to parliamentary intervention. Whether these laws apply has important implications for industry, as they include the practicalities and cost of engaging adequately skilled contractors for specialist tasks on major projects. Another recent example is the Australian Council of Trade Unions (ACTU) advocating for the application of the harmonised workplace health and safety regulations to the offshore industry. The application of these regulations would likely affect the extent of union involvement in the workplace, and have consequent cost and efficiency implications. In this extended abstract the author examines the impacts on industry of: recent and upcoming changes in employment regulation; uncertainties around the application of employment laws offshore; proposed changes to safety regulation; and, areas where industry is seeing advocacy for change.

Compact Flanged Connections for High Temperature Applications

2002 ◽  
Author(s):  
Sjur Lassesen ◽  
Frank Woll
Keyword(s):  
Oil And Gas ◽  
High Reliability ◽  
Oil And Gas Industry ◽  
Temperature Dependent ◽  
Static Behavior ◽  
Element Analysis ◽  
Gas Industry ◽  
Start Up ◽  
Low Weight ◽  
Offshore Industry

The Steelproducts Offshore Compact Flange System (SPO CFS) has proven to be an exceptionally good flange design for the oil and gas industry with service temperatures normally ranging from −100°C to +250°C. High reliability, small size and low weight are properties the offshore industry has appreciated. The design relies on a high bolt pre-tension in order to obtain the double sealing capability and the static behavior. For limited temperatures, the high pre-tension can be applied without any risk of loosing the pre-tension when the operating temperature is reached. For high temperatures, the temperature dependent material properties in flange and bolt need to be carefully evaluated and taken into account when designing the connection. Finite element analysis simulating all relevant phases from flange make-up to process start up and shut down have been performed in order to study flange behavior such as bolt tension, flange stresses, and seal contact. Relatively simple analytical equations have been used in order to predict the flange behavior and hence been basis for choosing bolting material, prestress and flange face angle. For process industry dealing with temperatures up to 720°C, it is now possible to use compact flanges. The use of compact flanged connection will first of all increase the reliability of the flanged connection, reducing the need for maintenance.

Reduced manning with improved safety and reliability: how classification societies and digital solutions can support operators

2019 ◽  
Vol 59 (2) ◽  
pp. 821
Author(s):  
Mark Tipping
Keyword(s):  
Oil And Gas ◽  
Human Life ◽  
Oil And Gas Industry ◽  
Detailed Knowledge ◽  
Gas Industry ◽  
Safety And Reliability ◽  
Offshore Industry ◽  
Near Future ◽  
Design Construction

The oil and gas industry is moving steadily towards automation and remote control of processes, which has the added advantage of removing personnel from the immediate danger of the offshore workplace. However, significant challenges remain to be met before the more complex type of offshore facility (especially floating facilities) can be operated fully unmanned, particularly when it comes to maintenance and repair campaigns. In particular, even though human life may be protected, the consequence of a major pollution incident occurring as a result of lack of sufficient manned surveillance is increasingly unacceptable in today’s society, and solutions have to protect these requirements as well. With today’s technologies and the pace of innovation, it is not difficult to envisage facilities in the near future where manned intervention is reduced to a far lower level than currently prevalent, perhaps even eliminated as robotics steadily advance. We can already begin to consider design features and systems that will make new facilities ready for such advances so that projects can absorb benefits from innovation as it occurs. The role of independent bodies such as the classification societies is to assess the design, construction and operation of offshore facilities and issue certification that gives regulators, financiers and insurers alike the confidence to support developments. For floating facilities this includes formal classification and a requirement for detailed knowledge of the state of the structure. This paper explores the methods that the classification society can use to support the aims of the offshore industry for reduced manning with improved safety and reliability.

Wellhead Fatigue Damage Based on Indirect Measurements

2015 ◽  
Author(s):  
Guttorm Grytøyr ◽  
Fredy Coral ◽  
Halvor Borgen Lindstad ◽  
Massimilliano Russo
Keyword(s):  
Fatigue Damage ◽  
Oil And Gas ◽  
Time History ◽  
Bending Moment ◽  
Oil And Gas Industry ◽  
Fatigue Properties ◽  
Marine Riser ◽  
Gas Industry ◽  
Blowout Preventer ◽  
The Moment

Enabling safe and reliable operations of subsea wellheads has a high priority in the global oil and gas industry. The objective of the current paper is to provide a novel method for bending moment estimates at the wellhead based on indirect moment measurements; this moment, together with fatigue properties are then used for fatigue damage estimation. Indirect bending moments are based on inclinations and accelerations measured by motion reference units (MRU) attached to blowout preventer (BOP), lower marine riser package (LMRP) and lower riser joint (LRJ) immediately above the lower flexible joint (LFJ). Also, required is the tension time history in the same period at the LRJ. The proposed methodology here can be implemented and integrated into a portal for data acquisition and visualisation. In order to validate the proposed method for indirect bending moment estimation, strain gages have been attached to a BOP and marine riser during drilling operations offshore Norway. Strain gage readings are transformed to bending moment which is used as reference (the so-called direct moment). The proposed method is used to calculate the moment indirectly, the so-called indirect moment. The resulting indirect moments agree very well with the direct moments.

Sign in / Sign up

Export Citation Format

Share Document