Methodology for Assessing Wellhead Integrity During its Life Cycle

2020 ◽  
Author(s):  
Marcelo A. Jaculli ◽  
José Ricardo P. Mendes ◽  
Kazuo Miura ◽  
Danilo Colombo
Keyword(s):  
Life Cycle ◽  
Coupled System ◽  
Current Speed ◽  
Christmas Tree ◽  
Sea State ◽  
Peak Period ◽  
Environmental Loads ◽  
Well Integrity ◽  
Operational Safety ◽  
Offshore Oil

Abstract The wellhead is an important component in the context of well integrity and operational safety, as it serves as a link between well and riser in offshore oil wells. Wellheads, combined with the BOP and/or the Christmas Tree, act as the final barrier element preventing leakage of oil from the well into the environment. The wellhead must sustain loads from the casings, which are hung into it through the casing hangers, as well as sustain loads from the riser, which is connected at the top of the BOP (right above the wellhead) through the lower flex joint. In this work, we propose a methodology for analyzing the wellhead, considering a mechanical system that couples the vessel, the riser, the wellhead itself, the conductor and surface casings, and their interaction with the soil. The simulation of this coupled system provides the loads that are transmitted to the wellhead due to its coupling with riser, vessel, casing, and soil. Then, these loads are converted into stresses and a criterion, such as yield, is applied to verify if they will cause wellhead failure. The objective of this work is to assess wellhead failure due to environmental loads (waves, currents) acting on the riser, by varying parameters such as significant wave height, peak period and current speed, as well as assess wellhead integrity during its lifecycle for operational and survival conditions. Results show that the wellhead may fail under certain environmental conditions, which would compromise well integrity and cause leakage from the well. The analysis performed here, which is deterministic, also provides a basis for a subsequent probabilistic analysis from which the wellhead reliability can be found, based on uncertainties such as the sea state parameters.

scholarly journals Sintering Behavior, Thermal Expansion, and Environmental Impacts Accompanying Materials of the Al2O3/ZrO2 System Fabricated via Slip Casting

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3365
Author(s):  
Justyna Zygmuntowicz ◽  
Magdalena Gizowska ◽  
Justyna Tomaszewska ◽  
Paulina Piotrkiewicz ◽  
Radosław Żurowski ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Life Cycle ◽  
Coefficient Of Thermal Expansion ◽  
Raw Materials ◽  
Slip Casting ◽  
Ceramic Materials ◽  
Sintering Behavior ◽  
Environmental Loads ◽  
Practical Applications ◽  
Technical Ceramics

This work focuses on research on obtaining and characterizing Al2O3/ZrO2 materials formed via slip casting method. The main emphasis in the research was placed on environmental aspects and those related to the practical use of ceramic materials. The goal was to analyze the environmental loads associated with the manufacturing of Al2O3/ZrO2 composites, as well as to determine the coefficient of thermal expansion of the obtained materials, classified as technical ceramics. This parameter is crucial in terms of their practical applications in high-temperature working conditions, e.g., as parts of industrial machines. The study reports on the four series of Al2O3/ZrO2 materials differing in the volume content of ZrO2. The sintering process was preceded by thermogravimetric measurements. The fabricated and sintered materials were characterized by dilatometric study, scanning electron microscopy, X-ray diffraction, and stereological analysis. Further, life cycle assessment was supplied. Based on dilatometric tests, it was observed that Al2O3/ZrO2 composites show a higher coefficient of thermal expansion than that resulting from the content of individual phases. The results of the life cycle analysis showed that the environmental loads (carbon footprint) resulting from the acquisition and processing of raw materials necessary for the production of sinters from Al2O3 and ZrO2 are comparable to those associated with the production of plastic products such as polypropylene or polyvinyl chloride.

scholarly journals Sea State Monitoring by Ship Motion Measurements Onboard a Research Ship in the Antarctic Waters

2021 ◽  
Vol 9 (1) ◽  
pp. 64
Author(s):  
Silvia Pennino ◽  
Antonio Angrisano ◽  
Vincenzo Della Corte ◽  
Giampaolo Ferraioli ◽  
Salvatore Gaglione ◽  
...  
Keyword(s):  
Transfer Functions ◽  
Wave Spectrum ◽  
Weather Forecast ◽  
Ship Motion ◽  
State Monitoring ◽  
Sea State ◽  
Peak Period ◽  
Research Ship ◽  
Antarctic Waters ◽  
The Antarctic

A parametric wave spectrum resembling procedure is applied to detect the sea state parameters, namely the wave peak period and significant wave height, based on the measurement and analysis of the heave and pitch motions of a vessel in a seaway, recorded by a smartphone located onboard the ship. The measurement system makes it possible to determine the heave and pitch acceleration spectra of the reference ship in the encounter frequency domain and, subsequently, the absolute sea spectra once the ship motion transfer functions are provided. The measurements have been carried out onboard the research ship “Laura Bassi”, during the oceanographic campaign in the Antarctic Ocean carried out in January and February 2020. The resembled sea spectra are compared with the weather forecast data, provided by the global-WAM (GWAM) model, in order to validate the sea spectrum resembling procedure.

Technical Analysis of Ocean Towing Evolutions

2021 ◽  
Author(s):  
Bartley Eckhardt ◽  
Daniel Fridline ◽  
Richard Burke
Keyword(s):  
Failure Modes ◽  
Human Life ◽  
Single Point ◽  
Forensic Analysis ◽  
Sea State ◽  
Worst Case ◽  
Strain Monitoring ◽  
Load Limit ◽  
Offshore Oil

Ocean towing in general, and non-routine tows in particular, present unique technical challenges to towing vessel owners/operators, salvors, the offshore oil/gas and wind industries, and others. When such tows “go wrong”, the harm to human life, property and/or the environment can be significant. The authors have drawn from their work on the Towing Safety Advisory Committee’s investigation of the grounding of the MODU Kulluk to present methods and considerations in analyzing ocean towing evolutions, both “routine” and “non-routine”. (TASK 14-01) The methods and considerations presented should be employed in advance of a towing evolution, but can be used in accident reconstruction and forensic analysis when an evolution has failed. The methods presented are iterative, and consider 2 x 6 degree freedom of motion (of the towing vessel(s) and towed vessel respectively) and characteristics of the towline, and facilitate determination of: Worst Case Conditions. Extreme Towline Tension (ETT) as a function of sea state and speed. Limits of the Tow (Go-No Go Criteria). Recommended Catenary Length as a function of sea state and speed. Size and Selection of the Towing Vessel and Gear, including: Required Bollard Pull. Required Strength, Characteristics and Condition of the Towline. Limits and Set Points of the Towing Winch, Automatic or Manual. Required Strength and Characteristics of the Synthetic Emergency Towline and its methods of deployment and connection. Working Load Limit (WLL) of the Shackles, Delta Plate and Attachment Points. Required Strength and Characteristics of Bridles, Pendant and Surge Gear/Shock Lines. The authors further explore the implications of single point failure modes, redundancy in gear and towing vessel(s), high cycle fatigue, and strain monitoring.

Bionomics of the pine needle scale (Hemiptera: Diaspididae), an emerging pest in Christmas tree (Pinaceae) plantations in southern Québec, Canada

2018 ◽  
Vol 150 (5) ◽  
pp. 632-636 ◽  
Author(s):  
Jean-Frdéric Guay ◽  
Amy Bernier-Desmarais ◽  
Jean-François Doherty ◽  
Conrad Cloutier
Keyword(s):  
Life Cycle ◽  
Scale Insects ◽  
Tree Plantations ◽  
Christmas Tree ◽  
Pine Needle ◽  
Abies Fraseri ◽  
Fraser Fir ◽  
Christmas Trees ◽  
Significant Damage ◽  
The Status

AbstractThe pine needle scale, Chionaspis pinifoliae (Fitch) (Hemiptera: Diaspididae), has the status of an emerging pest in Christmas tree (Pinaceae) plantations in Québec, Canada. The scale is not known to cause any significant damage yet and is not generally monitored by growers. However, it can be an obstacle for exportation to Christmas tree markets where scale insects are strictly regulated. In this study, we describe its life cycle in Christmas tree plantations in southern Québec. We confirm the presence of both parthenogenetic and sexual forms of the scale on Fraser fir Abies fraseri (Pursh) Poiret (Pinaceae) grown as Christmas trees, and of parasitoid and Coccinellidae (Coleoptera) specialists that could contribute to its control.

An Idealization of Wave Scatter Diagram for Spectral Fatigue Analysis

2009 ◽  
Author(s):  
Min Han Oh ◽  
Ki Myung Lee ◽  
Young Sik Jang
Keyword(s):  
Fatigue Analysis ◽  
Scatter Diagram ◽  
Analysis Method ◽  
Sea State ◽  
Environmental Loads ◽  
Wave Data ◽  
Wave Measurements ◽  
Spectral Models ◽  
Wave Heights ◽  
Significant Wave Heights

A spectral fatigue analysis method is most popularly applied for the detailed design of FPSOs. As the environmental loads at the installation site are directly calculated in the spectral analysis, this method gives the most reliable results although it needs much time-consuming works to fully reflect the environmental loads. As the technology of wave measurements advances, the measured wave data increase. Also their spectral models are very complicated because these include many wave components such as swells and wind seas. Since much time and effort are needed to treat these enormous and complicated wave data for the spectral fatigue analysis, a rational idealization of wave data is definitely required. In this paper, wave scatter diagram at Offshore Nigeria was reviewed and their idealization method was proposed. The influence level of each sea state of the wave scatter diagram was identified considering the fatigue damage levels estimated from the significant wave heights and dominant fatigue load RAOs. The sea states giving small fatigue damages were lumped symmetrically by merging or disregarding while those giving large fatigue damages were kept as original. For the validation of this method, the comparisons of dominant fatigue loads and representative fatigue damages were presented for the idealized wave scatter diagram and the original one. From these comparison works, it was confirmed that the idealized wave scatter diagram gives reliable results with reduced amount of calculation work.

A Life-Cycle Based Approach to the Remanufacturing Printing Supplies in Shanghai

2014 ◽  
Vol 878 ◽  
pp. 57-65 ◽  
Author(s):  
Yuan Zhou ◽  
Jing Wei Wang ◽  
Jian Feng Bai ◽  
Wen Jie Wu
Keyword(s):  
Life Cycle ◽  
Raw Materials ◽  
External Environment ◽  
Waste Stream ◽  
Environmental Loads ◽  
Pollution Emission ◽  
Great Pressure ◽  
Acidification Potential ◽  
Toner Cartridge

With the fast growing of printing supplies industry in Shanghai, it creates a large waste stream of obsolete printing supplies and causes great pressure on the environment. The information of remanufacturing printing supplies in Shanghai is gathered and waste stream is analyzed. As a case study of original toner cartridge and remanufacturing toner cartridge is compared in the context of life cycle methodology. The results show raw materials, energy consumption and pollution emission of the remanufactured toner cartridge are less than these of original toner cartridge. Environmental loads equitant including global warming potential, acidification potential, photo-oxidant formation potential, solid waste and fume from remanufacturing toner cartridge are cut 3.61%, 3.84%, 15.24% and 22.52% comparing to original toner cartridge. Its significance is that remanufacturing printing supplies can be more profitable and less harmful to the external environment than conventional manufacturing process. It also discusses strategies for lowering the environmental burden to promote the remanufacturing printing supplies in Shanghai.

Innovative Approach for Use of Hydrofoils on Ultralight Seaplane

2020 ◽  
Author(s):  
Antonio Maglione ◽  
Ubaldo Cella ◽  
Marco E. Biancolini ◽  
Leonardo Lecce
Keyword(s):  
Life Cycle ◽  
Power Plant ◽  
Life Cycle Cost ◽  
Water Surface ◽  
Maintenance Cost ◽  
Wave Forces ◽  
Water Spray ◽  
Sea State ◽  
Important Benefit ◽  
Plant Maintenance

Retractable hydrofoils may enhance performances of seaplane during take-off and landing runs by lowering the speed when the hull is leaving or touching water surface. Hydrofoils are designed to complement airlift with additional hydrodynamic lift elevating the hull above the water at a speed lower than take-off speed; this minimizes slamming phenomenon on the hull, improving seakeeping capability of the seaplane, since water impacts are minimized compared to conventional configuration and, as a consequence, forces and accelerations on airframe, crew and passengers are reduced. This is of foremost importance on ultralight seaplanes, where wave forces acting on the relatively small aircraft mass provide high accelerations and significant roll, pitch and yaw forces that are higher on light aircraft compared to heavy seaplanes. As matter of facts, clear advantage of this configuration is the increase of sea state when a light seaplane can safely fly, providing additional useful days along the year. Important benefit is the improvement of seaplane performances during take-off and landing, reducing duration of the most critical flight phases, increasing overall safety and reducing pilot workload. Further benefits are envisioned, with optimization of wing, empennage and fuselage to minimize aero-drag and, as snow-ball effect, mission fuel consumption and energy power requirements. Life-cycle cost receives benefits too, since less water spray is ingested by engine and less water droplets impinge on fast revolving propeller, thus reducing expensive power plant maintenance cost over the entire service life.

Proposition of Operational Maps As Tools for Evaluating Safety During the Emergency Disconnection of Risers

2018 ◽  
Author(s):  
Marcelo Anunciação Jaculli ◽  
José Ricardo Pelaquim Mendes ◽  
Kazuo Miura ◽  
Márcio Yamamoto
Keyword(s):  
Material Properties ◽  
Drilling Fluid ◽  
Environmental Loads ◽  
Finite Elements Modeling ◽  
Sea Bottom ◽  
Open Sea ◽  
Operational Safety ◽  
Waves And Currents ◽  
Drilling Operations ◽  
Water Depths

The construction of subsea wells under deep water depths brought the necessity to understand the behavior of columns on such conditions. These columns can be risers, drill strings or casing strings, which are either being installed by lowering them until they reach the sea bottom and/or inside the well, or they are already connected and fully operational. Since these columns are exposed to the open sea, environmental loads such as waves and currents will affect them. Depending on how harsh these environmental conditions are, drilling operations may be suspended. Therefore, understanding how such loads interact with such columns are of the utmost importance if one wants to ensure operational safety. In this paper, we discuss about the problem of emergency disconnections of risers. The concern of doing an emergency disconnection is fundamental for ensuring operational safety because the well will lose a safety barrier, as the level of the drilling fluid inside the well can no longer be controlled after the riser is disconnected, and thus the fluid cannot maintain its downhole pressure anymore. This work focuses on a finite elements modeling of riser dynamics, with the appropriate applied loads, to verify under which sea conditions the riser must be disconnected. The result of such analysis is called an “operational map”, which displays the maximum values of stress along the riser as a function of different sea conditions. Using the riser material properties, this map can then be divided in two regions — failure and admissible — and thus one can see for which sea conditions the riser must be disconnected to avoid its failure. The contribution of the present study is proposing a methodology to elaborate an operational map for a given riser scenario, from which both failure and admissible regions can be seen for emergency disconnection operations.

scholarly journals Study of the Installation Process of the Subsea Tree Passed Through the Splash Zone

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1014
Author(s):  
Yufang Li ◽  
Honglin Zhao ◽  
Ning Xu ◽  
Xiaoyu Wang ◽  
Deguo Wang
Keyword(s):  
Wave Height ◽  
Oil And Gas ◽  
Splash Zone ◽  
Safety Standards ◽  
Engineering Software ◽  
Safe Production ◽  
Operational Safety ◽  
Offshore Oil And Gas ◽  
Marine Engineering ◽  
Offshore Oil

The subsea tree is one of the critical pieces of equipment in the subsea production system, and its installation is related to the safe production of offshore oil and gas. Due to the differences in the form of the structures, the speed of entering the water, the marine environment, and other factors, the process of the structure entering the water is exceedingly complicated. During the engineering installation, the most dangerous phase involves the structure passing through the splash zone. Based on the theory of the movement of the subsea tree passing through the splash zone, Lingshui 17-2 subsea tree installation was analyzed with the marine engineering software OrcaFlex, and a sensitivity analysis of the lowering of the subsea tree was performed. During the splash zone phase, the wave height had the highest impact on the subsea tree, affecting the horizontal offset and cable load, which may lead to the oil tree capsizing and cable breakage. Furthermore, the velocity only affected the horizontal offset, and the overall effect was not noticeable. The operational safety window for the subsea tree installation was established according to the operational safety standards. Therefore, the recommended lowering speed was 0.50 m/s, while the flow velocity should not exceed 1.50 m/s, and the wave height should not be higher than 4.5 m.

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