Numerical Simulations of Ocean Drilling System Behavior With a Surface or a Subsea BOP in Waves and Current

Author(s):  
Celso K. Morooka ◽  
Raphael I. Tsukada ◽  
Dustin M. Brandt

Subsea equipment such as the drilling riser and the subsea Blow-Out Preventer (BOP) are mandatory in traditional systems used in deep sea drilling for ocean floor research and petroleum wellbore construction. The drilling riser is the vertical steel pipe that transfers and guides the drill column and attached drilling bit into a wellbore at the sea bottom. The BOP is used to protect the wellbore against uncontrolled well pressures during the offshore drilling operation. Presently, there is a high level of drilling activity worldwide and in particular in deeper and ultra-deeper waters. This shift in depth necessitates not only faster drilling systems but drilling rigs upgraded with a capacity to drill in the deep water. In this scenario, two general drilling systems are today considered as alternatives: the traditional system with the subsea BOP and the alternate system with the surface BOP. In the present paper, the two systems are initially described in detail, and a numerical simulation in time domain to estimate the system behavior is presented. Simulations of a floating drilling rig coupled with the subsea and surface BOP in waves and current are carried out for a comparison between the two methods. Results are shown for riser and BOP displacements. Critical riser issues for the systems are discussed, comparing results from both drilling system calculations. Conclusions are addressed showing advantages and disadvantages of each drilling system, and indicating how to correct the problems detected on each system.

Author(s):  
John F. Greene ◽  
Dara Williams

With drilling and exploration activity currently high in both deep and shallow water regions rig availability and selection is an issue for operators to consider in order to achieve the desired exploration schedule. At present the industry focus is on the development of 6th generation drilling rigs with the capacity to operate in increasing deep water. However despite the focus on deepwater exploration and the associated demand for deepwater drilling rigs there still exists demand for drilling rigs that can operate in shallow to moderate water depths (100m–500m). In addition, certain field development scenarios may exist where planned water depths for drilling activities vary significantly and therefore a drilling rig and riser system is required that can operate satisfactorily in both shallow and deep water depths. For a given drill site, rig availability or well location, may be such that an operator may have to select a modern deepwater 6th generation rig for shallow water activities where a 3rd generation rig would appear to provide a better solution. Other considerations such as vessel station keeping requirements may lead to selection of a 6th generation rig over a 3rd generation rig, as the former tend to have improved DP thrusters capacity. However it is also important to note that while the 6th generation rigs may have been proven to be robust systems for operation in deep water, the response of a 6th generation drilling system in shallow water depths can be very different to that of an older 3rd generation rig and drilling riser system. Thus careful consideration must be made by the operator when considering the selection of drilling vessels for shallow to moderate water depths. Fatigue life of the wellhead is shown to be affected when one compares the response of the 6th generation and 3rd generation drilling systems in shallow to moderate depths. This also needs to be accounted for when selecting rigs for workover or intervention operations on older infrastructure. This paper presents a discussion on the various parameters such as BOP stack size, riser, flex joint and vessel design that influence the response of the drilling system in shallow to moderate water depths (100m–500m). A number of case studies and parametric studies have been carried out and the results of these are presented in order to compare the wellhead fatigue damage from the older 3rd generation systems with the 6thgeneration systems and also to identify the critical drivers for this fatigue life reduction.


Author(s):  
Zewen Xu ◽  
Zheng Rong ◽  
Yihong Wu

AbstractIn recent years, simultaneous localization and mapping in dynamic environments (dynamic SLAM) has attracted significant attention from both academia and industry. Some pioneering work on this technique has expanded the potential of robotic applications. Compared to standard SLAM under the static world assumption, dynamic SLAM divides features into static and dynamic categories and leverages each type of feature properly. Therefore, dynamic SLAM can provide more robust localization for intelligent robots that operate in complex dynamic environments. Additionally, to meet the demands of some high-level tasks, dynamic SLAM can be integrated with multiple object tracking. This article presents a survey on dynamic SLAM from the perspective of feature choices. A discussion of the advantages and disadvantages of different visual features is provided in this article.


Author(s):  
Lichao Xu ◽  
Szu-Yun Lin ◽  
Andrew W. Hlynka ◽  
Hao Lu ◽  
Vineet R. Kamat ◽  
...  

AbstractThere has been a strong need for simulation environments that are capable of modeling deep interdependencies between complex systems encountered during natural hazards, such as the interactions and coupled effects between civil infrastructure systems response, human behavior, and social policies, for improved community resilience. Coupling such complex components with an integrated simulation requires continuous data exchange between different simulators simulating separate models during the entire simulation process. This can be implemented by means of distributed simulation platforms or data passing tools. In order to provide a systematic reference for simulation tool choice and facilitating the development of compatible distributed simulators for deep interdependent study in the context of natural hazards, this article focuses on generic tools suitable for integration of simulators from different fields but not the platforms that are mainly used in some specific fields. With this aim, the article provides a comprehensive review of the most commonly used generic distributed simulation platforms (Distributed Interactive Simulation (DIS), High Level Architecture (HLA), Test and Training Enabling Architecture (TENA), and Distributed Data Services (DDS)) and data passing tools (Robot Operation System (ROS) and Lightweight Communication and Marshalling (LCM)) and compares their advantages and disadvantages. Three specific limitations in existing platforms are identified from the perspective of natural hazard simulation. For mitigating the identified limitations, two platform design recommendations are provided, namely message exchange wrappers and hybrid communication, to help improve data passing capabilities in existing solutions and provide some guidance for the design of a new domain-specific distributed simulation framework.


2006 ◽  
Vol 40 (1) ◽  
pp. 29-35
Author(s):  
K. Moran ◽  
M. Paulson ◽  
M. Lengkeek ◽  
P. Jeffery ◽  
A. Frazer

A new deep water drilling system was developed and applied to recover deeply buried sediments for scientific analyses in one of the deep rift valley lakes of Africa—Malawi. This approach overcame the difficulty of maintaining position over a drill site in a remotely located, large, deep lake. Environmental conditions in Lake Malawi are similar to deep water marine settings and, as such, a marine approach was adopted for the Lake Malawi Drilling Project (LMDP). In February and March 2005, the modified pontoon, Viphya, successfully completed a scientific drilling expedition in Lake Malawi. This expedition recovered core at depths greater than 380 m below lake-floor in water depths as great as 600 m. The major refit of Viphya included installation of a moonpool, bridge, crew accommodations, mess, washroom, power system, dynamic positioning, and a drilling system. These major modifications required early pontoon surveys and naval architectural analyses and design work prior to their commencement. The expedition also used modified scientific coring tools with a marine geotechnical drilling rig for the first time, resulting in excellent core recovery and quality.


Author(s):  
F. Politz ◽  
M. Sester

<p><strong>Abstract.</strong> Over the past years, the algorithms for dense image matching (DIM) to obtain point clouds from aerial images improved significantly. Consequently, DIM point clouds are now a good alternative to the established Airborne Laser Scanning (ALS) point clouds for remote sensing applications. In order to derive high-level applications such as digital terrain models or city models, each point within a point cloud must be assigned a class label. Usually, ALS and DIM are labelled with different classifiers due to their varying characteristics. In this work, we explore both point cloud types in a fully convolutional encoder-decoder network, which learns to classify ALS as well as DIM point clouds. As input, we project the point clouds onto a 2D image raster plane and calculate the minimal, average and maximal height values for each raster cell. The network then differentiates between the classes ground, non-ground, building and no data. We test our network in six training setups using only one point cloud type, both point clouds as well as several transfer-learning approaches. We quantitatively and qualitatively compare all results and discuss the advantages and disadvantages of all setups. The best network achieves an overall accuracy of 96<span class="thinspace"></span>% in an ALS and 83<span class="thinspace"></span>% in a DIM test set.</p>


2020 ◽  
Vol 30 (1) ◽  
pp. 63-90

The article examines the state of the history of science as a discipline and its objectives in the context of its origins and current transformations. The establishment of this discipline and its assumptions about the nature of science together with its goals and structure are briefly discussed. The history of science became a discipline only at the beginning of the second half of the 20th century, and its start is associated with the work of chemist James Conant, a high-level administrator in Manhattan project who was also president of Harvard University and a high-ranking bureaucrat. It was based also on the narrative developed by Alfred North Whitehead, Edwin Burtt, Alexandre Koyré and other historians of science, which claimed modern science was the creator of modernity and a necessary condition for the geopolitical domination of the West. In that understanding, modern science meant science since the time of Galileo and Newton. The author provides a critical analysis of this foundation narrative for the discipline and of its consequences while showing how contemporary history of science has overcome it. The contradiction between modernism and historicism has been resolved in favor of the latter. A key role in this was played by the book The Structure of Scientific Revolutions by Thomas Kuhn, which held the potential to undo the presumed monolithic unity of science by rejecting teleology and introducing incommensurability and discontinuities into the historical process. By rejecting explanation of the knowledge of other times and places in terms of modern science, the discipline faced a radical multiplication of independent types of knowledge. This was facilitated by the reorientation to the study of knowledge practices that took place in the 1980s. As a result, the subject matter of the history of science began to erode, and this launched discussion of the prospects for a transition to a history of knowledge based on the study of practices. The sweep of this change of vision is illustrated by the example of classifying sciences according to both their subject matter and the similarities in their research practices. Finally, the advantages and disadvantages of the new discipline along with its prospects and the challenges it faces are discussed.


2012 ◽  
Vol 241-244 ◽  
pp. 1482-1486
Author(s):  
Jian Wen Zhao ◽  
Wei Xie

This paper mainly focuses on designing an open CNC system. At first, the advantages and disadvantages of the three popular open numerical control technologies were discussed, and on the basis of demands analysis, this paper chose motion controller plus PC as the whole system model. Then, according to the system model, this article designed the hardware system for the control system, including choosing multi-axis motion control card, servo motors and their drivers. Thirdly, based on the features of this open numerical control system, the paper designed and put the software into three levels, namely low level of control software, mid-level of communication software, and high-level of management software respectively. Finally, in order to test the control performance of this open numerical control system, some experiments were carried out on a two-dimension motion platform, the results are satisfactory and error analysis on these experiments is also given out.


2020 ◽  
pp. 31-34
Author(s):  
O. M. Koryagina ◽  
E. S. Erastova ◽  
T. V. Skvortsova

The article considers the use of the quantum levitation property of a superconductor for the modernization of a new type of drilling rig system. The diagrams of the propulsion system of the rig, on the basis of which conclusions are made about the profitability and economic efficiency of the drilling rig, are provided. The use of the quantum levitation effect can be rationally used in drilling rigs, increasing the efficiency by 9%.


2021 ◽  
Author(s):  
Stig Settemsdal ◽  
Saverio Ventrelli

Abstract The paper presents a novel approach for modernizing/retrofitting offshore drilling rig power plants with islanded direct current (DC) power grids and energy storage. The concept has been successfully applied on several offshore rigs which are in operation today and is applicable to jack-ups, semi-submersibles, drill ships, as well as other types of marine support vessels for oil and gas platforms and wind farms. The approach aims to enhance the feasibility of leveraging energy storage solutions on offshore drilling rigs and marine vessels by making use of the existing power plant footprint. Unique measures have also been incorporated into the electrical system architecture to ensure that the reliability and safety of the existing alternating current (AC)-based system are not compromised. This enables operators to capitalize on the numerous benefits of energy storage (e.g., reduced emissions, enhanced dynamic performance for drilling and dynamic positioning, etc.) without having to perform a "rip and replace" of the entire power plant and electrical infrastructure.


2021 ◽  
Author(s):  
Paola Rossi ◽  
Itai Sela ◽  
Adam Rizika ◽  
Diogenes Angelidis ◽  
Mark Duck ◽  
...  

Abstract An alternative methodology using new preventative technology to manage cybersecurity exposure on deepwater drilling rig assets is presented. For the past two years Shell's Deepwater Wells business has been evaluating typical cyber defence approaches and undertaken cybersecurity risk assessments and penetration tests. These activities have demonstrated the challenges attaining cybersecure drilling rig environments. Whilst cyberattacks increase in frequency, adaptability, and become cheaper to launch, regulatory and liability insurance requirements are also evolving. To achieve the goal of cyber-resilience, a major Operator has collaborated with a cybersecurity firm to trial technology for rapidly and reliably protecting deepwater rigs. The paper presents aspects of the numerous challenges faced and offers a different approach using new technology applied to both supplement and accelerate the attainment of a cyber-resilient environment onboard deepwater drilling rigs. It shares the deep dive lessons learnt leading to a more comprehensive understanding of how to protect drilling rigs and their safety critical control systems. Aside from addressing technical attributes using risk vs. maturity based methods, the approach also caters to business demands of short term rig contracts, managing multi-vendor legacy systems and satisfying increasing digitalisation/remote access needs with associated reductions in overall cybersecurity CAPEX spend.


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