bluuebunny/crossref_metadata_2025_split huggingface dataset:
Engineered Oilwell-cement-based Systems for Optimum Validation of Cased-hole Ultrasonic Tools
Authors: Jimenez Walmy Cuello , Pang Xueyu , Gilstrap Tatiana 
Published: June 2014

Abstract
Cement is a critical component in an oil well because it provides sealing and zonal isolation within the well. To help ensure proper performance of a cementing operation, various evaluation techniques/tools have been developed and used over the years, including some based on ultrasonic pulse echo technology. Ultrasonic pulse echo evaluation tools can play a key role in determining in-situ cement performance and if any remedial cementing is required. As the oil and gas industry continues to migrate toward more challenging reservoirs with increasingly harsh conditions, and coupled with more stringent regulatory requirements, significant technology improvements are helping ensure well integrity and safety. For example, ultrasonic tools are being reengineered for the capability to penetrate thick-walled casings (&gt;0.75 in.) commonly used in complex situations, such as deepwater and high-pressure/high-temperature (HP/HT) wells. Meanwhile, there is also great demand for better optimized validation techniques to confirm the operational performance of these new evaluation tools. This paper focuses on investigating the use of oilwell cements as validation media of current and advanced ultrasonic tools designed for cement and casing evaluations.
The evaluation system developed in this study consists of a combination of various validation media with a wide range of acoustic impedances (1.5 to 8.5 MRayl) and a multicasing fixture with casing wall thicknesses ranging from 0.4 to 1.4 in. This system could be used for the evaluation of tool performance in the presence of various muds and across a range of temperature and pressure conditions. Performance effectiveness was evaluated by measuring the acoustic impedance of the different media bonded to a multithickness casing and comparing the results to those acquired by direct acoustic measurement performed on the same media. The evolution of acoustic properties over time, directly related to cement hydration, was also monitored.
An advanced pulse echo technology tool was used to perform preliminary validation using the newly developed evaluation system. This resulted in a clear trend of impedance evolution that correlates well with the direct impedance measurement of cement media.
Incorporating Completion and Drilling Techniques to Enhance and Maximize Production Over the Life of the Well
Authors: Smith Lee , Scott Greg 
Published: June 2014

Summary
This paper describes application of an integrated approach that combines drilling and completion techniques in a new use of reaming tools currently used for reaming-while-drilling (RWD) operations, in a way that minimizes the need for SOP of using a dedicated reamer run. The RWD application provides the enhanced wellbore geometry needed to design and engineer solutions using maximum size (OD) conventional casing, liners, expandable casing and multiple swellable packers. This type of assembly for drilling /completion design, currently utilized in multiple Williston Basin wells, ND, is shown to consistently result in shorter drilling time and successful first casing/liner runs. Currently this type of cross functional approach has been used on over 400 wells/ 4,000,000 ft. of lateral.
Wellbore Strengthening and Casing Smear: The Common Underlying Mechanism
Authors: van Oort Eric , Razavi Seyed Omid 
Published: June 2014

Abstract
A variety of Wellbore Strengthening (WBS) methods have been introduced and successfully applied in field drilling practice over the last decade, with origins going back to the late 1980's when the DEA13 investigation was carried out. In addition, a beneficial casing "smear" effect has been observed in recent years during drilling-with-casing or casing-while-drilling (CWD) operations, preventing lost circulation even when drilling highly depleted formations at high annular circulating pressures. Casing smear mimics WBS effects observed during regular drilling operations in its ability to effectively extend fracture gradients and prevent lost circulation, which is of great benefit to drilling difficult wells with tight drilling margins such as (ultra-)deepwater wells. In fact, when used appropriately, WBS and casing smear may offer well construction benefits that are on par with those of managed pressure drilling (MPD) and dual gradient drilling (DGD), at reduced equipment usage, complexity and cost.
To explain WBS and casing smear phenomena, a variety of different mechanisms have been proposed. These broadly fall into three categories: (1) Wellbore Stress Augmentation (WSA) - augmenting the hoop stress or closure stress around the wellbore by propping open induced fractures either at the wellbore face or somewhere into the fracture; (2) Fracture Propagation Resistance (FPR) - effective solids plugging of any fracture tip, thereby interfering with effective fracture growth; (3) Wellbore Face Sealing (WFS) - forming a uniform seal around the wellbore that prevents fluid leak-off and interferes with fracturing. Here, we offer a re-examination of previously published data (such as open-hole leak-off tests) and theoretical results, and present our own independent results and assessments to show that WBS and casing smear have a common, unified origin. It will be shown that the only mechanism that consistently explains all the data obtained to date is, in fact, the FPR mechanism. Moreover, guidelines are presented to exploit FPR optimally for the benefit of complex well construction.
First Field-Testing Of A New Rotary Steerable Drilling Liner Technology On Alaska North Slope
Authors: Hobbs Greg , Stinson Rob , Alvord Chip , Anyanwu Okechukwu N. , Klotz Christian , Mohammad Muntasar 
Published: June 2014

Abstract
Conventional drilling through lower intermediate intervals in the southern portion of the Alpine field on Alaska's North Slope (ANS) has posed significant challenges, resulting in longer than planned well delivery timing, and additional costs due to accumulated drilling complications. While unstable shale sections can be drilled without significant issues, hole collapse has caused difficulties while tripping out of hole and running casings. The need to overcome these challenges for long term economical access to develop the Alpine sands reservoir section beneath the shale layers led to numerous project initiatives and operational changes. These actions all produced incremental advances to mitigate wellbore stability issues, but never provided a guarantee that a liner would be successfully run to total depth of the open hole section after the trips required to complete this task conventionally.
In 2011, a new Steerable Drilling Liner system was proposed as a possible solution for drilling these wellbores while sealing off the troublesome shales. An extensive feasibility study was conducted to ascertain the technical possibility of deploying this technology safely within the Alpine field. Candidate wells were identified and a phased implementation approach was adopted to conduct field trials in order of increasing complexity of well trajectory and open hole and liner section lengths. This paper provides insights into the new technology and the field trial program. We cover the lessons learned and further improvement opportunities applicable to future deployments in this area. Based on the success of the Steerable Drilling Liner technology in this application, further deployments are scheduled to take advantage of developing Alpine reservoir sands in an economical and safe manner.
Macondo Litigation Update - How Court Decisions Will Impact Oilfield Contracting and Insurance Practices
Authors: Moomjian Cary A. 
Published: June 2014

Abstract
Decisions in the Macondo litigation pending in a U.S. District Court in New Orleans will impact operators, drillers, service and supply companies as well as insurance underwriters.
Phases I and II of the Macondo trial have been concluded. Phase III is expected to commence in the first half of 2014. The paper primarily reviews pre-trial, trial and appellate court proceedings relating to the contractual indemnification, release and insurance provisions of the applicable drilling and cementing contracts that BP entered into with Transocean and Halliburton, respectively. The paper includes commentary from the author based on over 35 years of experience as a drilling company legal, contractual and risk management executive.
Initial pre-trial Macondo Court rulings addressed whether contractual indemnification or releases may apply even in the event of gross negligence, strict statutory liability or willful misconduct. These rulings also determined whether indemnification may include punitive damages or apply to penalties assessed under the Oil Pollution Act of 1990 ("OPA'90"), the Clean Water Act ("CWA") or the Outer Continental Shelf Lands Act ("OCSLA"). In future proceedings, the Court is expected to determine if a material breach of contract will invalidate traditional oilfield indemnity and release provisions.
Trial and appellate court rulings in Macondo-related litigation have considered the nature and scope of insurance coverage accorded to BP as an additional insured party under Transocean's liability insurance policies. These rulings focus on both the drilling contract provisions naming BP as an additional assured and the terms of the associated insurance agreements. Although this litigation is currently under a second appellate review, the important implications of these proceedings on oilfield contracts and insurance agreements are discussed in the paper.
There can be no doubt that the Macondo litigation will have a profound impact on the way oilfield activities are conducted, contracted and insured. The paper is intended to assist those involved in contracts and risk management in understanding the judicial proceedings and determining how they may impact oilfield contracts and insurance agreements.
Expanding the Extended Reach Envelope at Chayvo Field, Sakhalin Island
Authors: Gupta Vishwas P. , Yeap Angel H. , Fischer Kyle M. , Mathis Randall S. , Egan Michael J. 
Published: June 2014

Abstract
The second drilling campaign at the Chayvo field, located offshore Sakhalin Island, targeted the development of a new reservoir zone using extended reach wells from onshore. A total of 4 oil producers and 1 gas injector were planned to develop the northern portion of the reservoir. To effectively drain the east and west flanks of this reservoir, record length wells beyond the current extended reach drilling (ERD) envelope were required. Key challenges included high torque and drag, wellbore positioning in a thin oil column, wellbore stability, long horizontal completions, and downhole tool telemetry. This paper describes the Operator's experience with drilling these challenging wells that resulted in several new ERD records. Key well design features, equipment upgrades, and lessons learned will be discussed.
ERD is an established technique to economically access reserves from existing infrastructure, reducing the need for additional drill centers and consequently reducing the drilling and facilities environmental footprint. Continuing advancement of the ERD envelope along with delivering cost-effective wells will further maximize the benefits of this technique. The case history described in this paper illustrates that the advancement of the ERD envelope is possible through detailed planning, technical design, and operational excellence.
The planning of these wells built upon the Operator's previous ERD experience along with additional tools and techniques. Three of the project wells set new worldwide ERD records for measured depth; the longest well, Z-42, established new records for measured depth (12,700m) and horizontal reach (11,739m). Completion designs were optimized to successfully run a ∼3,600m long open hole completion, and the well was finished in ∼70 days. As a result of this successful development, additional wells are being planned in conjunction with technology advancement initiatives that will push the ERD measured depth envelope to 13km and longer.
Experimental Assessment of Casing Expansion as a Solution to Microannular Gas Migration
Authors: Kupresan Darko , Heathman James , Radonjic Mileva 
Published: June 2014

Abstract
The objective of this research was to investigate the potential impact of expandable casing technology on the remediation of Sustained Casing Pressure (SCP). Varying magnitudes of SCP exist in the Gulf of Mexico (GOM), where over 80% of casing strings exhibiting SCP are production and surface casings, representing a great technical, economic, and environmental risk. Situations in which SCP is observed usually result in costly and frequently unsuccessful remediation efforts.
The technique proposed in this project with expandable casing can be done during drilling, producing, or during the abandonment process. A unique bench-scale physical model was used to simulate expansion of a previously-cemented casing under field-like conditions. Experimental measurements obtained during low-percentage casing expansion exhibited improvement of cement integrity with significant changes in the cement sheath. Successful multi-rate flow-through experiments with nitrogen gas showed the effectiveness of this technique in complete closure of microannular gas leakage pathways, providing ideal cement remediation. If implemented, this technology has potential to become a cement remediation technique for leaks behind the casing.
A Field-Based Method of Calibrating Inclinometers for Floating Drilling and Completion Operations with Applications of the Method to Reduce Differential Flex Joint Angles
Authors: Mouton David E. , Newberry David R. 
Published: June 2014

Abstract
Inclinometers in deepwater drilling and completion operations provide essential information These devices are either manual ("bullseyes") or Electronic Riser Angle (ERA) systems that report angles of subsea equipment such as BOP's, flex joints, and wellheads. These readings, particularly from the manual devices, can be inaccurate if not properly calibrated or "zeroed" on floating vessels. As a result, important operational decisions may be based on erroneous inclinometer readings. Incorrect decisions based on such readings could lead to a unnecessary stop in operations or a continuance of operations that may cause damage to subsea pressure containment equipment, with a resultant potential risk to the operability of this critical safety system.
Could Emulsified Friction Reducers Prevent Robust Friction Reduction?
Authors: Tucker Kristen M. , McElfresh Paul M. 
Published: June 2014

Abstract
Many of the friction reducers in use today demonstrate various degrees of performance based on the type of mixing water utilized, especially those products which are designed as an "emulsion" (Aften et al. 2009; Zelenev et al. 2009). In addition to molecular differences between various polyacrylamides, the nature of the oil external qualities of an emulsion can pose challenges to breaking (or inverting) the emulsions (Aften et al. 2009; Zelenev et al. 2009). These factors directly affect hydration rates and are dependent on water quality factors like salinity, dissolved materials, suspended materials, and pH (Aften et al. 2009; Zelenev et al. 2009).
Therefore, it is postulated that if the friction reducers are applied in another form such as a powder or slurried powder, they could have an inherent broader spectrum of applicability and efficiency. The purpose of this study is to determine the differences in performance of several friction reducers in various water qualities in order to determine if the type of polymer application enhances or restricts the range of applicability. Multiple polyacrylamides are tested in different forms including oil external emulsions, powder, and slurried powder. These friction reducers are tested on a flow loop in up to four different water qualities including fresh water, 5% KCl, sea water, and produced water.
The results of this testing show that some oil external emulsions are limited to smaller ranges of applicable water qualities. The powder polyacrylamide sample has a broad range of applicability, while the slurried powder shows comparable and often superior performance, especially in poor water quality.
Switching to a slurried powder friction reducer would enhance operational simplicity and economies of scale by eliminating the need for several products. The percent polymer activity would also surpass that of emulsions which could ultimately reduce the total volume pumped and, in turn, cost, emissions, time, and truck traffic due to freight.
One Tcf From One Well: The Design of a 500 MMscf/D Subsea Well for Offshore Mega Gas Fields
Authors: Reeves Donald F. , Healy John C. 
Published: June 2014

Abstract
With the continued discovery of large gas fields worldwide that have highly prolific sandstone reservoirs, the ability to design wells capable of recovering ultra-high volumes of gas will become of great interest. The project teams for these fields will be challenged to develop the fields with the smallest well count possible. The results from this study could prove useful to production and completion teams supporting large gas field developments. This paper presents a study to determine the feasibility of a subsea sand control gas well producing at rates up to 500 MMscf/D and recovering one trillion cubic feet (Tcf) of gas. Because the size of recent gas field discoveries is so large, reservoir simulation models will show that recoveries exceeding one Tcf are possible from a single location. Considering the huge cost to install deep water subsea sand controlled wells, reducing the total well count necessary to deplete the field is a business imperative. The results of the study show that completing a sand control well that can produce 500 MMscf/D and recover one Tcf is plausible. The details of the well productivity, completion design concepts and relevant comparison of analogue fields is shown. In conclusion, production and completion engineers involved in development of mega gas fields should at least consider planning for such wells.
Chemical Qualification and Field Application of a Nondamaging Scale Squeeze Treatment in the Mangala Field
Authors: Chavan Chetan , Rao Eshwar , Jha Mihir , Tiwari Shobhit , Graham Gordon , Stalker Robert 
Published: June 2014

Abstract
Significant production rate decline and a few ESP failures were observed in the Mangala field, onshore India, due to scaling. Scale inhibitor squeeze treatments were required to arrest the production decline and prevent additional ESP failures. The Mangala crude oil is extremely waxy, with a wax appearance temperature (WAT) of 62°C and a reservoir temperature of 65°C. This meant that prior to chemical application, fluids would have to be pre-heated to prevent wax formation and potential damage to the near wellbore area. The produced water chemistry included iron concentrations in the region of 5 - 15 mg/l, which was related to the presence of significant quantity of siderite within the formation and which could have resulted in potential formation damage due to iron dissolution when applying pre-selected acid-phosphonate inhibitors. Additionally, the two main producing formations FM3 and FM 4 are produced from long horizontal wells completed with stand-alone screens. Chemical placement in the wells therefore proved to be a significant challenge, and treatments were designed to achieve placement across the water producing zones.
This paper describes the squeeze chemical selection for minimisation of formation damage risks associated with treatments in this particularly challenging case study, with WAT close to reservoir temperature and the presence of reactive iron minerals. The impact that these factors had on both chemical performance and on the potential applicability of the selected chemicals is discussed. The paper also discusses pre-conditioning treatments pumped in these wells to regain productivity. The work also demonstrates how a combination of laboratory testing and treatment modelling has been used to minimise the potential for formation damage while at the same time maximising chemical treatment of the water producing zones. The detailed mineralogy and heterogeneity of the reservoir formations, the impact of production conditions and elevated iron on the performance of the selected chemicals are all described as well as the selection of alternative generic chemicals which were not poisoned by the increased iron. Initial field treatments have been conducted and preliminary results will also be presented which concur with the chemical qualification and treatment design
A Novel Slow-Release Rheology Modifier for Well Treatment Fluids
Authors: Li Leiming , Zhou Jia , Sun Hong , Qu Qi 
Published: June 2014

Abstract
Fluids with high viscosity are needed during hydraulic fracturing to convey the high pressure to create fractures in the rock formation, and to carry the proppant downhole to hold these fractures open after the treatment. A number of oxidative breakers, live and/or encapsulated, are usually mixed into the fluids upon pumping downhole to break the fluids after the treatment to flow back fluids and minimize the damage to the formation. It is not always easy to control the breaking rate of these breakers. If they break the fluids too early in the treatment, the fracturing fluids may not effectively create fractures, and screenout may occur. Well treatment fluids for other oilfield applications may also require controllable slow-release rheology modifiers.
A novel rheology modifier has been identified recently and successfully used in a number of well treatment fluid systems. In one example, the rheology modifier can be used to break crosslinked fracturing fluids at desired rates. By adding the rheology modifier into the fracturing fluids prepared with the crosslinked polysaccharides, the fully controllable breaking of the fluids has been realized in our laboratory tests. In another example, the rheology modifier can be used to create a temporary plug that gradually self-breaks at a controllable rate. Low-residue and salt-tolerant hydroxyethyl cellulose (HEC) solution can be crosslinked into a viscous gel and used as a temporary gel plug. By including the rheology modifier at selected concentrations in the gel, the originally thick temporary plug can be gradually thinned to flowable fluid after the preset period of time. This way, the temporary plug can be easily removed from the wellbore after it has served its purpose. The performance of the rheology modifier in the selected well treatment fluid systems will be discussed.