Offshore Units Research Articles

Offshore concrete structures

In the offshore industry there are two possible materials for the construction of the hull of any structure: steel and concrete. Steel is being widely used in the shipbuilding industry for merchant ships, warships, etc. Materials such as aluminium, glass reinforced plastic (GRP) or timber are also used in small units with lengths lower than 100m and with less adverse conditions than in the offshore industry. Nevertheless, some ships/barges have been built of concrete in the past, but these have been rather isolated cases and have not changed the industry practice. During the First and Second World War concrete was used due to the scarcity of other materials, so the series of barges by Alfred A. Yee were a rare exception. Other floating structures were also made in concrete, but they are almost anecdotal. However, the behaviour of these concrete structures, especially in terms of maintenance, has been excellent. Therefore, the fact that concrete has not had an adequate reception so far in shipbuilding does not mean that it will not be the material best suited to the offshore industry in the future. The extra displacement and associated fuel costs in concrete ships have been found to be prohibitive in the past. However the loss of mobility in a concrete hull compared to a steel hull can be perfectly offset by the advantages offered by concrete, as the shipping and offshore industry now have very different priorities. One of the main differences in these priorities is the importance of maintenance and resistance to fatigue, precisely the areas where concrete performs the better. Ships can easily be dry-docked for maintenance and repair, while in the offshore platforms these works have to be done in situ, so maintenance and fatigue are crucial to them. Besides these aspects, concrete has other advantages, according to a number of findings in several studies. This supports the fact that in recent years concrete offshore units have been built proving that in certain cases the benefits of steel are inferior to those of concrete. Concrete gravity base platforms type Condeep have been building since the first unit became operational in 1976, together with a few floating platforms, that have geometry similar to those made of steel (barges, semi-submersibles and TLP type platforms). Offshore LNG terminals and offshore industrial plants utilise emerging concepts in concrete that are lasting for years. The life of these barges can be designed for up to 200 years, such as the floating Nkossa barge, so they can be a good alternative to the construction of these facilities on land, thus avoiding landfills on the coast that degrade the already punished coastline of industrialized countries. The challenge is precisely to optimize their capital costs to compete for an offshore installation against a shore facility. The environment will undoubtedly benefit from this great challenge that lies ahead in the XXI century.

Per una nuova Fincantieri. competenza per uscire dalla crisi

This paper aims to develop potential strategies for achievable and sustainable growth of the Italian shipbuilding industry by understanding the characteristics of this industry as well as the current market situation and future trends. The decrease in new orders in the niche market of cruise ships has become a serious risk for Fincantieri to manage. In the past two decades, the top management of Fincantieri has not mirrored the constant volume growth of global seaborne trade as well as the dramatic demand from the offshore industry, so giving way to stagnation of the overall productivity, uncontrollable growth of overheads, and gradual impoverishment in designing. Considering the current and perspective market situation, analyzing the strategy and capabilities of the major Korean shipbuilders, and evaluating strengths and weaknesses of Fincantieri as it is, I will suggest for a New Fincantieri some potential industrial and financial strategy: focusing on offshore units while keeping on cruising sector leadership, activating product diversification, and opening to international partnerships towards development of a global company.

Working in verticalized platform vessel: an ergonomic approach in the oil industry

In this paper we point some aspects of workers activities in offshore units in the oil industry. These units became more verticalized and have a greater number of operating systems. Our goal is to present the main difficulties that workers face in these units.

Analysis of Safety Requirements for Large Offshore Units Evacuation Systems. LSA safety function

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Risk in stability evaluation for floating offshore units

During the useful life of a vessel it undergoes various changes that lead to uncertainties in determining the displacement and center of gravity. Besides upgrading work, the very operation of the platform itself involving constant ballast and oil loading and unloading or the use of maintenance equipment can generates uncertainties concerning the displacement and center of gravity. These, therefore, are the parameters that present uncertainties inherent to the vessel's operations. Taking this into account, one example of the application of uncertainties on the displacement and transversal and vertical center of gravity positions will be presented in the analysis of the static stability of a converted FPSO tanker. Another question raised in this work is the deterministic treatment of certain criteria for the parameters that depend on random factors, such as wind, currents and waves. This paper will present a probabilistic approach for the calculation of the roll angle according to resolution IMO A.562 (environment criteria). The two chosen criteria for this analysis were resolutions IMO A.167 (general criteria) and A.562 (weather criterion).

Coordination of globally distributed teams: A co-evolution perspective on offshoring

This article examines the coordination of an organization's onshore and offshore units from a co-evolution perspective. Literature based insights are combined with a case study of a leading IT-services provider to build new theory and a related propositional inventory. Counter-intuitively, our analysis suggests that managerial intent to promote onshore–offshore task coordination, by founding it on a common organization-wide identity and work context, can spark political conflict and result in the sub-optimal use of knowledge, skills and tools on individual projects. The analysis also reveals that effective solutions to the coordination problem are likely to emanate bottom-up, from practices that have been distilled from a range of routines and experiences as project teams learn and progressively accumulate knowledge of what works and what does not. We highlight the crucial role in this process of the senior management, proper timing of an offshore team's involvement in a project, horizontal communication and a joint onshore–offshore evaluation and reward system.

Captive Offshoring of New Product Development in Brazil

This paper focuses on captive offshoring of new product development (NPD), i.e., relocating projects or project phases to foreign-based, wholly-owned, multinational corporation (MNC) subsidiaries (captive offshore units) to benefit from cost and efficiency advantages and/or from access to complementary technological resources and capabilities. Adopting a host country perspective, we theorize why different forms of local collaboration may complement or conflict with efficiency-seeking or arbitrage strategies and may thus influence why captive offshore units receive new product development orders from other MNC units located abroad. Using a sample from Brazil and applying structural equation modeling with partial least squares (PLS), we find that local NPD outsourcing constitutes a complementary relationship, while local cooperation with clients creates a trade-off relationship with captive offshoring. That these relationships are moderated by the captive offshore unit’s cost position within the MNC suggests that arbitrage effects transcend the headquarter-subsidiary relationship into the sphere of MNC subsidiaries’ local collaborations. Our findings imply that arbitrage in multinational contexts affects the interdependence between resources and transaction costs.

Very High Cycle Fatigue Analysis of High Strength Steel with Corrosion Pitting

This work deals with very high cycle fatigue tests on high strength steel subject to the corrosive action of salt solution. Tests were carried out at constant load ratio R = -1 on corrosion treated and non-treated specimens and sea water flow specimens of R5 steel, which according to an International Classification Society of offshore systems is steel graded with the highest ultimate tensile strength to manufacture mooring chains and accessories intended to position mooring applications such as mooring of mobile offshore units, mooring of floating production units and mooring of offshore loading systems. Fatigue endurance on pre-corroded specimens was quite dispersed but with a mean value of 360 MPa, whereas for the non corroded specimens the fatigue endurance was located between 420 MPa at 105 - 106 cycles, and 380 MPa at 109 cycles. Concerning the sea water flow specimens, important increase in fatigue life is observed in reducing the applied load. Dispersion on fatigue endurance for the pre-corroded and sea water flow specimens was related to the complex process of corrosion on the specimen surface; nevertheless, the resulting pitting holes were associated to fracture origin in these specimens. Furthermore, fatigue failure origin was systematically localized at a circular, elliptical or irregular surface pitting hole formed during the corrosion process; special attention was focused on the pitting holes related to fatigue failure. Finite element results were obtained for the hemispherical voids placed on the specimen surface in order to determine the corresponding stress concentration; these results were associated with the real fracture origin pitting holes observed on specimens with pre-corrosion and sea water flow corrosion. Finally, some conclusions were obtained concerning pitting holes, stress concentration and fatigue life for the pre-corroded and sea water flow corroded specimens.

Enabling role of governance in strategizing and implementing KM

PurposeKM governance plays a vital role in KM strategy planning and its implementation. Despite the importance of KM governance, empirical research in this area so far has been limited. This research seeks to show how a federated and self‐governance framework enabled effective KM strategy planning and implementation in a captive offshoring unit in India.Design/methodology/approachThe approach takes the form of an in‐depth study of KM strategy planning and implementation process in a captive offshore unit of a leading financial services company, using the case research method.FindingsThe research shows that a KM program, driven by a federated governance for strategizing and a self‐governance for implementation, results in successful adoption, practice and sustenance of organization‐wide KM. In addition, self‐governance has also helped the organization to achieve an efficient single‐person‐driven KM function to manage the entire KM program. KM function should be reporting to a governance committee (chosen from across the business units of the organization) rather than a single leadership position.Research limitations/implicationsThe findings are based on a study of a single organization and therefore it may have limitations in its applicability in other settings. However, it brings out the importance of federated and self‐governance in effective and efficient KM strategy planning and implementation. A KM council, comprising the CEO, BU heads, and the CKO to spearhead the entire strategy planning helps in successful KM strategy implementation. It suggests that the commitment of senior management and functional managers can be achieved by suitably linking their contribution to KM with their goals and KRAs.Practical implicationsTo make the KM program successful, organization‐wide KM governance has to precede strategy. The research shows how the Balanced Score Card may be used to align KM initiatives with the business strategy. Ownership among the senior managers and heads of business units can be achieved by making their contribution to KM part of their KRAs. The KM head (CKO) should be reporting to the governance committee rather than a single leadership position.Originality/valueThe research paper provides both theoretical and practical insights into how federated and self‐governance as an approach for KM governance enables effective and efficient KM strategy planning and implementation.

Repair of floating offshore units using bonded fibre composite materials

On ships, tankers and similar vessels structural defects such as cracks and corrosion damage are typically repaired by welding. However, welding is unwanted hotwork on floating offshore units (FOUs) such as floating, production, storage and offloading (FPSO) and floating, storage and offloading (FSO) vessels because it requires shutdown of parts of the vessel thus resulting in expensive production delays. Bonded fibre composite material patch repairs can be used as an alternative to overcome the hazards of hotwork associated with welding. The patches are bonded over the defect and the integrity of the original structure is hence restored. The patch repair technology can also be utilised to provide upgrades, such as life extensions and higher design requirements. A recommended practice (RP) has been developed that describes requirements for patch repairs used in FOUs. To provide flexibility and to fit different repair needs, the RP defines a range of Repair Classes that can be used depending on the urgency of the repair and the need for optimisation. The qualification effort increases with the degree of optimisation. The requirements are based on an extensive test program carried out in the laboratory (reported elsewhere) as well as experience from full-scale repair demonstrators. Two full-scale repair demonstrators were carried out on actual FOUs to demonstrate the feasibility of the RP for bonded composite patch repair. In addition the demonstrators also showed the viability of using bonded composite repairs under harsh conditions encountered in oil and gas exploration and production environments. The first repair was carried out to arrest a fatigue crack that had developed from the corner of a door, while the second repair was carried out to restore material loss on a heavily pitted deck floor. Both repair cases are used as examples to demonstrate the proposed qualification procedures whilst at the same time discussing the challenges and potential applications of this patch repair technology for FOUs in the oil and gas industry.

The earthing of intrinsically safe barriers on offshore transportable equipment

The author has been involved during the last two years in the compliance of an offshore coiled-tubing unit which required certification to hazardous-area product standards and installation-standard compliance. As part of this work there was a need to investigate in greater depth the usage of zener barrier on board offshore transportable equipment. The question of earthing zener barriers offshore is reviewed and analysed from various sources – zener barrier manufacturers, international publications, standards and technical papers. This paper explains the difficulty of proper zener barrier earthing on board offshore transportable equipment. It proposes an engineering methodology to solve this issue. When zener barriers are still required, a solution is proposed for their earthing and the installation is studied with a hazard analysis and risk control (HARC) approach.

Une évaluation des performances économiques de la pêche côtière : le cas de la Bretagne

La pêche professionnelle occupe une place significative dans le tissu socioéconomique de certaines zones littorales. Les flottilles exerçant l’essentiel de leur activité dans la bande côtière méritent une attention particulière. L’activité des flottilles côtières est généralement mal connue, ce qui limite la capacité à porter un diagnostic sur leur viabilité économique. Prenant pour cas d’étude la Bretagne, cet article évalue le poids et les performances économiques de la pêche côtière. Les résultats indiquent que les performances économiques de ces flottilles ne sont pas inférieures à celles des flottilles hauturières. Les navires côtiers présentent des atouts importants, en termes d’intensité énergétique et de capacité à opérer hors financements publics. En l’absence de mesures de régulation de l’accès adaptées à leurs spécificités techniques, ils sont vulnérables à la pression exercée par les navires hauturiers sur les ressources de la bande côtière.

Risk-based strategies for the next generation of maintenance and inspection programs

The maritime industry has seen an ever-increasing interest in applying risk-based approaches to better manage the integrity of ships and offshore units in service. The recent initiatives related to IMO in setting Goal Based Standards will also be reflected in justification of maintenance and inspection regimes for marine assets from a performance based standpoint. The development of risk-based strategies for the next generation of maintenance and inspection programs for various ship includes the application of Reliability-Centered Maintenance (RCM) for machinery systems and Risk-Based Inspection (RBI) for hull structures and fixed equipment systems.

THANH, T.-D. &amp; KHUC V. (eds) 2006. Stratigraphic Units of Vietnam. 526 pp. Hanoi: Vietnam National University Publishing House. Price US $40.00 plus postage (hard covers). No ISBN; publisher's serial number 1K-22DH 2006

THANH, T.-D. &amp; KHUC V. (eds) 2006. Stratigraphic Units of Vietnam. 526 pp. Hanoi: Vietnam National University Publishing House. Price US $40.00 plus postage (hard covers). No ISBN; publisher's serial number 1K-22DH 2006 - Volume 144 Issue 5

Are US Multinationals Making Rational Offshoring Decisions? A Gravity Model Approach

This paper constructs five indicators that a multinational firm must take into account when deciding the location of its offshore units. These indicators are: human capital; skilled labour cost; quality of infrastructure; business environment; and market size. The indicators are based on over 100 different underlying variables. The paper then ranks 51 economies of the world from 'most attractive country' to 'least attractive country' on the basis of these five indicators and studies the responsiveness of US foreign direct investment to these fundamentals in a gravity model framework. Our random effects estimations show that English language capabilities, market size, telecommunication infrastructure and business environment are the factors that are most important in shaping the location decisions of US multinationals. Distance is also seen to play an important role, indicating a preference for a 24/7 staffing model among US multinationals.

Toward Limit State Design of Ships and Offshore Structures Under Impact Pressure Actions: A State-of-the-Art Review

In design of ships and ship-shaped offshore units, issues related to impact pressure actions arising from sloshing, slamming, green water, or explosion are of particular concern. The structural response under impact pressure actions is quite different from that under static or quasistatic actions. It has been recognized that the limit state approach is a more rational basis for structural design and safety assessment where both "demand" (loads) and "capacity" (strength) must be accurately defined. For impact pressure action cases, the demand is associated with hydrodynamics areas, taking into account the characteristics of impact pressure-time history, and the structural capacity is associated with structural mechanics areas, considering geometric and material nonlinearities together with strain rate sensitivity. This paper reviews recent advances and trends toward future limit state design of ships and offshore structures under impact pressure actions.

Enabling a Powerful Marine and Offshore Decision‐Support Solution Through Bayesian Network Technique

A powerful practical solution is by far the most desired output when making decisions under the realm of uncertainty on any safety-critical marine or offshore units and their systems. With data and information typically being obtained incrementally, adopting Bayesian network (BN) is shown to realistically deal with the random uncertainties while at the same time making risk assessments easier to build and to check. A well-matched methodology is proposed to formalize the reasoning in which the focal mechanism of inference processing relies on the sound Bayes's rule/theorem that permits the logic. Expanding one or more influencing nodal parameters with decision and utility node(s) also yields an influence diagram (ID). BN and ID feasibility is shown in a marine evacuation scenario and that of authorized vessels to floating, production, storage, and offloading collision, developed via a commercial computer tool. Sensitivity analysis and validation of the produced results are also presented.

Experimental Analysis of the Near Wake from a Ducted Thruster at True and Near Bollard Pull Conditions Using Stereo Particle Image Velocimetry (SPIV)

Thrusters working at low advance coefficients are employed in a wide range of offshore and marine applications on Floating, Production, Storage, and Offloading (FPSO) systems; shuttle tankers; tug boats; and mobile offshore units. Therefore, an understanding of the flow around the thrusters is of great practical interest. Despite this interest, there is lack of knowledge in the description of the hydrodynamic characteristics of a ducted thruster’s wake at bollard pull and low advance coefficient values. This work was aimed at providing detailed data about the hydrodynamic characteristics of a Dynamic Positioning (DP) thruster near wake flow at different low advance coefficient values. Wake measurements were made during cavitation tunnel tests carried out on a ducted propeller model at the Italian Ship Model Basin (INSEAN), Rome, Italy. Through these experiments, the DP thruster near wake velocity components at different downstream axial planes, up to 1.5 diameters downstream, were obtained using a Stereoscopic Particle Image Velocimetry (SPIV) system. These experiments were carried out at different advance coefficient (J) values [bollard pull (J=0), J=0.4 and J=0.45].

The Tuna Offshore Unit: Concept and Operation

A radical new concept for delivering Bluefin Tuna to the marketplace is proposed offering offshore technologies to the world's fish industry. The Tuna Offshore Unit is a 190-m length and 56-m breadth vessel that resembles a semisubmersible with a catamaran hull and internal arrangement of fish-pools that can be enlarged in operation by deploying a rigid net for fish cultivation. Using the vessel, juvenile bluefin tuna are purchased at selling centers (e.g., hatcheries), fattened to a total bio-mass of 1200 tons over a period of nine months in warm-water climates and delivered to live fish markets during periods of high demand. This paper describes the main features, working principles, and design challenges of the Tuna Offshore Unit.

A fracture mechanics interpretation of the DNV brittle fracture criteria for ships and mobile offshore units

ABSTRACT Design procedures against brittle fracture are either based on empirical experience based methods or theoretical fracture mechanics based methods. Frequently, the fracture mechanics based assessment procedures are suspected to be tools by which to get acceptance for poor quality. In reality, these suspicions are somewhat unfounded, since the manufacturing standards, implicitly, also assume some specific defect size. The standards contain specific inspection criteria, which in themselves lead to some specific possible accepted defect size. The problem has been that the manufacturing standards have not been evaluated based on an advanced fracture mechanics analysis. Here the Det Norske Veritas (DNV) rules for ships and mobile offshore units are analysed, applying the state‐of‐the‐art fracture mechanics assessment method SINTAP. Based on the assessment, the consistency of the DNV rules, with respect to strength level and inspection criteria is revealed. The assessment, also creates the possibility to extend the rules to thinner and higher strength steels.