Surface Casing Cum Production Casing Well Design – Extreme but Techno-economically Acceptable Approach

2021 ◽  
Author(s):  
M Hatta M Yusof ◽  
Rahimah A Halim ◽  
Nurfaridah Ahmad Fauzi ◽  
Ahgheelan Sella Thurai ◽  
M Zulfarid Khalid ◽  
...  
Keyword(s):  
Low Cost ◽  
Oil Price ◽  
Significant Component ◽  
Field Development ◽  
Well Integrity ◽  
Well Design ◽  
Open Hole ◽  
Well Trajectory ◽  
Fit For Purpose

Abstract 2020 marks another challenging year for O&G sector, with the operators being in an uphill battle to survive the plunging oil price. With CAPEX rationalization underway, future field development may only be prospective via implementation of low-cost Field Development Plan (FDP). As well cost is a significant component of development CAPEX, low well cost must be pursued, by designing fit-for-purpose wells. For relatively shallow (≈2000 m-MD in meterage drilled) wells, a simple well design consisting of only two-hole sections (excluding Conductor) shall be considered. This design approach though, may require the Surface Casing to also be the Production Casing (if only Production Liner will be ran in the production hole section or if open hole completion is feasible or if cemented monobore completion strategy is adopted). This aspect of casing design (having Surface cum Production Casing) does indeed pose well integrity concerns as the quality of cement behind the Surface cum Production Casing is uncompromisable to ensure no gas can breach to surface. This paper discusses the design measures than can be incorporated into the well trajectory, cementing plan, and production surveillance in order to support the feasibility of Surface cum Production Casing concept.

Delivering More Fit-for-Purpose Wells with Low Cost Approach at Untapped Area Matured Field – Application of Cone Concept Statistical Approach

2021 ◽  
Author(s):  
M. Hatta M. Yusof ◽  
M. Zarkashi Sulaiman ◽  
Rahimah A. Halim ◽  
Nurfaridah Ahmad Fauzi ◽  
Ahgheelan Sella Thurai ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Statistical Approach ◽  
Control Method ◽  
Low Cost ◽  
Volatile Oil ◽  
Field Application ◽  
Well Design ◽  
Execution Phase ◽  
Sand Control ◽  
Fit For Purpose

Abstract This paper discusses the Case study of Field A in offshore Sarawak, Malaysia which focus on re-thinking development based on statistical analysis of the fields. Conventionally, well design is driven by subsurface requirement by targeting the high-reserve sand and well is designed to meet subsurface objectives. However, the conventional way may not be efficient to develop matured field environment due to the high CAPEX and the inconsistencies among well design especially in current volatile oil price period. The objective of this fit-for-purpose approach which is called "Cone Concept Statistical Approach" is to steer away from the conventional way of targeting only sweet spots whilst leaving the remaining potential resources undeveloped. Based on the statistical analysis and subsurface fields pattern, the "Cone Concept Statistical Approach" in which standardizing well design and trajectories was developed to extract the whole fields’ reserve at maximum. Well design boundaries were introduced to ensure this approach can be replicated throughout the field. Not only this study covers drilling perspective, completion perspective was also taken into consideration by exploring a cheaper and fit for purpose sand control method, considering it is a matured field with relatively short remaining field life. The Well Cost Catalogue for this field-specific approach was also developed which contains different types of design and completion, in order to holistically evaluate sand control method and identify the best option for the project moving forward. This "Cone Concept Statistical Approach" aims to enable operator to drill simple wells within the same allocated budget in which poses low-to-no risk in the design and execution phase. This promotes a learning curve to improve operation & HSE, and ultimately gets positive project economics. Since this simple approach can be implemented early on even during the pre-FEL stage, the FDP team & host authority can come together to jointly discuss the targets/platform ranking and segregate them into various phases. Hence, the number of platforms or drilling centers, and its location also can be optimized early on with this concept, and again, translating into further reduction in overall project cost. This paper will help other operators and host authority to understand better on how a specific development concept on statistical approach can result and turn the matured-challenging fields into more economically attractive projects – low overall development cost and maximizing the recovery.

Game Changing Cementless Annular Isolation Improving Economical Returns in Deep Water Wells

2021 ◽  
Author(s):  
Manfred Bledou ◽  
Didier Caillon ◽  
Benjamin Groschaus ◽  
Guillaume Viger ◽  
Harpal Singh ◽  
...  
Keyword(s):  
Substantial Reduction ◽  
Innovative Technology ◽  
Pressurized Water ◽  
Field Development ◽  
Increased Risk ◽  
Open Hole ◽  
Well Trajectory ◽  
Zonal Isolation ◽  
Field Deployment ◽  
The Cost

Abstract This paper will discuss a game-changing and innovative technology that enabled cementless annular isolation (liner to borehole) across the reservoir, removing the risk of previous experienced cost and time overrun from complex cement operations and securing the full economical return on the wells. The technology has been deployed in four Moho North Albian wells, drilled through a complex reservoir with highly laminated lithology requiring efficient zonal isolation for both acid treatment and water shut off. During the earlier field development, many cementing challenges were encountered that increased risk and cost and the ability to deliver effective isolation across the reservoir. Poor isolation leads to poor matrix acid stimulation, higher skin and a higher risk of water production. To address this the operator sponsored an industry challenge to achieve reservoir isolation with cost and risk reduction and to deliver overall efficiency gains. Through dialogue between the Operator and a leading service provider in Open Hole Zonal Isolation, a solution was identified that would effectively replace the cement across the reservoir with a metal expandable annular sealing system. Time for delivery was a key driver to meet the drilling schedule and materialize the cost and risk reductions on the remaining wells. A scope of work was completed that included extensive qualification, manufacture and field deployment. The solution has proven to deliver benefits that address several fundamental aspects which were associated with the cemented liners: Substantial reduction in risk and cost associated with drilling the extended rat hole (shoe track) into the highly pressurized water zone (+/- 100mMD)Removed the risk and cost for the additional run to under ream the 6 ½″ hole to 7 ¼″ (low-ROP)Provided more certainty for zonal isolation whilst delivering effective acid stimulation and maintaining the low skin values. The technology has many different applications within wells where conventional cement is challenged beyond its capabilities and inherently not fit for purpose, due to factors such as well trajectory, hole geometry, reservoir uncertainty, downhole environment (pressure, Temp, ECD) etc. Within these environments, the technology developed for Moho North adds a proven solution to the Operators toolbox, a technology that is already finding alternate applications and planned deployments.

Assurance of Long-Term Well Integrity in Highly Corrosive Downhole Environment

2021 ◽  
Author(s):  
Mohammad Arif Khattak ◽  
Agung Arya Afrianto ◽  
Bipin Jain ◽  
Sami Rashdi ◽  
Wahshi Khalifa ◽  
...  
Keyword(s):  
Gas Production ◽  
Simulation Software ◽  
Successful Implementation ◽  
Horizontal Section ◽  
Well Integrity ◽  
Well Design ◽  
Cement System ◽  
Zonal Isolation ◽  
Fit For Purpose

Abstract Portland cement is the most common cement used in oil and gas wells. However, when exposed to acid gases such as carbon dioxide (CO2) and hydrogen sulfide (H2S) under downhole wet conditions, it tends to degrade over a period of time. This paper describes the use of a proprietary novel CO2 and H2S resistant cement system to prevent degradation and provide assurance of long-term wellbore integrity. The CO2-resistant cement was selected for use in one of the fields in Sultanate of Oman after a well reported over 7% CO2 gas production resulting in well integrity failure using conventional cements. The challenge intensified when the well design was modified by combining last two sections into one long horizontal section extending up to 1,600 m. The new proposed cement system was successfully laboratory- tested in a vigorous CO2 environment for an extended period under bottomhole conditions. Besides selecting the appropriate chemistry, proper placement supported by advanced cement job simulation software is critical for achieving long-term zonal isolation. The well design called for a slim hole with 1,600 m of 4 ½-in liner in a 6-in horizontal section where equivalent circulating density (ECD) management was a major challenge. An advanced simulation software was used to optimize volumes, rheologies, pumping rates, and ECDs to achieve the desired top of cement. The study also considered a detailed torque and drag analysis in the horizontal section, and fit- for-purpose rotating-type centralizers were used to help achieve proper cement coverage. To date, this cement system has been pumped in 32 wells, including 24 with 6-in slimhole horizontal sections with no reported failures. The paper emphasizes the qualification and successful implementation of fit-for-purpose design of CO2- and H2S-resistant cement as well as optimized execution and placement procedures to achieve long-term zonal isolation and well integrity in a complex slimhole horizontal well design.

Roma development drilling – evolution of well design and drilling performance

2019 ◽  
Vol 59 (2) ◽  
pp. 814
Author(s):  
Andrew Sellars ◽  
Thivanka Dedigama ◽  
Mohammad Zaman
Keyword(s):  
Large Scale ◽  
Continuity Of Operations ◽  
Drilling Performance ◽  
Well Design ◽  
Artificial Lift ◽  
Cost Reductions ◽  
Open Hole ◽  
Fit For Purpose ◽  
Work Programs ◽  
Continuous Work

Santos’ Roma field, located in the Surat Basin, has been producing coal seam gas (CSG) since 1988; however, development drilling did not commence until 2011. Since this time, well design has evolved to maximise access to coals and operability for artificial lift systems. Concurrently, performance has dramatically improved through scale of sanctioned work programs and revised contracting strategies, enabling continuous and sustainable time and cost reductions. This paper reviews Santos’ development drilling activity in the Roma CSG field since 2011, highlighting critical events and step changes. The following aspects are addressed: • Evolution of well design: A series of well designs have been trialled, ranging from deviated to vertical, fracture stimulated to open-hole slotted liner well types. Collaboration with both Reservoir Engineering and Production Operations have been critical in arriving at a fit-for-purpose design. • Effect of the industry downturn: The industry downturn spanning 2014–2016 presented an opportunity to reset and rationalise execution approach. • Operating and contracting model: The updated model focused on utilising a consistent, fit-for-purpose rig fleet and service companies, supported by lean office and field based operations teams. • Benefits of large scale, continuous work programs: The scale and continuity of operations are key to achieving continuous and sustainable time and cost reductions. • Opportunities: Future opportunities have been identified for ongoing optimisation in a changing market.

Delivering Low Cost Wells at Matured Field with Enhanced Statistical Approach

2021 ◽  
Author(s):  
M Hatta Mhd Yusof ◽  
M Zarkashi Sulaiman ◽  
Rahimah A. Halim ◽  
Nurfaridah Ahmad Fauzi ◽  
Ahgheelan Sella Thurai ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Statistical Approach ◽  
Control Method ◽  
Low Cost ◽  
Volatile Oil ◽  
Field Environment ◽  
Well Design ◽  
Execution Phase ◽  
Sand Control ◽  
Fit For Purpose

Abstract This paper discusses the Case study of Field A in offshore Sarawak, Malaysia which focus on re-thinking development based on statistical analysis of the fields. Conventionally, well design is driven by subsurface requirement by targeting the high-reserve sand and well is designed to meet subsurface objectives. However, the conventional way may not be efficient to develop matured field environment due to the high CAPEX and the inconsistencies among well design especially in current volatile oil price period. The objective of this fit-for-purpose approach which is called "Cone Concept Statistical Approach" is to steer away from the conventional way of targeting only sweet spots whilst leaving the remaining potential resources undeveloped. Based on the statistical analysis and subsurface fields pattern, the "Cone Concept Statistical Approach" in which standardizing well design and trajectories was developed to extract the whole fields’ reserve at maximum. Well design boundaries were introduced to ensure this approach can be replicated throughout the field. Not only this study covers drilling perspective, completion perspective was also taken into consideration by exploring a cheaper and fit for purpose sand control method, considering it is a matured field with relatively short remaining field life. The Well Cost Catalogue for this field-specific was also developed which contains different types of design and completion, in order to holistically evaluate sand control method and identify the best option for the project moving forward. This "Cone Concept Statistical Approach" aims to enable operator to drill more simple wells within the same allocated budget in which poses low-to-none risk in the design and execution phase, promoting learning curve to improve operation & HSE, and ultimately to get positive project economics. Since this simple approach can be implemented early on even during the pre-FEL stage, the FDP team & host authority can come together to jointly discuss the targets/platform ranking and segregate them into various phases. Hence, the number of platforms or drilling centers, and its location also can be optimized early on with this concept, and again, translating into further reduction in overall project cost. This paper will help other operators and host authority to understand better on how a specific development concept on statistical approach can result and turn the matured-challenging fields into more economically attractive projects – low overall development cost and maximizing the recovery.

Effect of Computerized Auditory Training on Speech Perception of Adults With Hearing Impairment

2013 ◽  
Vol 20 (3) ◽  
pp. 91-106 ◽  
Author(s):  
Rachel Pizarek ◽  
Valeriy Shafiro ◽  
Patricia McCarthy
Keyword(s):  
Hearing Loss ◽  
Speech Perception ◽  
Literature Review ◽  
Low Cost ◽  
Experimental Designs ◽  
Auditory Training ◽  
Hearing Impairments ◽  
Communicative Disorders ◽  
And Training

Computerized auditory training (CAT) is a convenient, low-cost approach to improving communication of individuals with hearing loss or other communicative disorders. A number of CAT programs are being marketed to patients and audiologists. The present literature review is an examination of evidence for the effectiveness of CAT in improving speech perception in adults with hearing impairments. Six current CAT programs, used in 9 published studies, were reviewed. In all 9 studies, some benefit of CAT for speech perception was demonstrated. Although these results are encouraging, the overall quality of available evidence remains low, and many programs currently on the market have not yet been evaluated. Thus, caution is needed when selecting CAT programs for specific patients. It is hoped that future researchers will (a) examine a greater number of CAT programs using more rigorous experimental designs, (b) determine which program features and training regimens are most effective, and (c) indicate which patients may benefit from CAT the most.

Driving Torsion Scans with Wavefront Propagation

2020 ◽  
Author(s):  
Yudong Qiu ◽  
Daniel Smith ◽  
Chaya Stern ◽  
mudong feng ◽  
Lee-Ping Wang
Keyword(s):  
Potential Energy ◽  
Force Field ◽  
Degrees Of Freedom ◽  
Computational Cost ◽  
Initial Guess ◽  
Field Development ◽  
Force Field Development ◽  
Wavefront Propagation ◽  
Open Source Software Package

<div>The parameterization of torsional / dihedral angle potential energy terms is a crucial part of developing molecular mechanics force fields.</div><div>Quantum mechanical (QM) methods are often used to provide samples of the potential energy surface (PES) for fitting the empirical parameters in these force field terms.</div><div>To ensure that the sampled molecular configurations are thermodynamically feasible, constrained QM geometry optimizations are typically carried out, which relax the orthogonal degrees of freedom while fixing the target torsion angle(s) on a grid of values.</div><div>However, the quality of results and computational cost are affected by various factors on a non-trivial PES, such as dependence on the chosen scan direction and the lack of efficient approaches to integrate results started from multiple initial guesses.</div><div>In this paper we propose a systematic and versatile workflow called \textit{TorsionDrive} to generate energy-minimized structures on a grid of torsion constraints by means of a recursive wavefront propagation algorithm, which resolves the deficiencies of conventional scanning approaches and generates higher quality QM data for force field development.</div><div>The capabilities of our method are presented for multi-dimensional scans and multiple initial guess structures, and an integration with the MolSSI QCArchive distributed computing ecosystem is described.</div><div>The method is implemented in an open-source software package that is compatible with many QM software packages and energy minimization codes.</div>

The system of indicators of the quality of the carbon-carbon composite materials and technologies of their production

2018 ◽  
pp. 127-132
Author(s):  
T. N. Antipova ◽  
D. S. Shiroyan
Keyword(s):  
Composite Material ◽  
Low Cost ◽  
Experimental Studies ◽  
Carbon Matrix ◽  
Carbon Composite ◽  
Optimal Number ◽  
Laboratory Equipment ◽  
Carbon Composite Material ◽  
Carbon Composite Materials

The system of indicators of quality of carbon-carbon composite material and technological operations of its production is proved in the work. As a result of the experimental studies, with respect to the existing laboratory equipment, the optimal number of cycles of saturation of the reinforcing frame with a carbon matrix is determined. It was found that to obtain a carbon-carbon composite material with a low cost and the required quality indicators, it is necessary to introduce additional parameters of the pitch melt at the impregnation stage.

scholarly journals Diagnostic Capabilities of a Smartphone- Based Low-Cost Microscope

2020 ◽  
Vol 6 (3) ◽  
pp. 522-525
Author(s):  
Dorina Hasselbeck ◽  
Max B. Schäfer ◽  
Kent W. Stewart ◽  
Peter P. Pott
Keyword(s):  
Low Cost ◽  
Field Of View ◽  
Parasitic Diseases ◽  
Optical Parameters ◽  
Trade Off ◽  
Resource Limited ◽  
Wide Range ◽  
Diagnostic Applications ◽  
Diagnostic Capabilities

AbstractMicroscopy enables fast and effective diagnostics. However, in resource-limited regions microscopy is not accessible to everyone. Smartphone-based low-cost microscopes could be a powerful tool for diagnostic and educational purposes. In this paper, the imaging quality of a smartphone-based microscope with four different optical parameters is presented and a systematic overview of the resulting diagnostic applications is given. With the chosen configuration, aiming for a reasonable trade-off, an average resolution of 1.23 μm and a field of view of 1.12 mm2 was achieved. This enables a wide range of diagnostic applications such as the diagnosis of Malaria and other parasitic diseases.

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