Unconventional Single Slurry Solution for ERD Wells with Depleted Formations

2021 ◽  
Author(s):  
Anibal Flores ◽  
Jorge Vasquez ◽  
Rama Anggarawinata ◽  
Lakmun Chan
Keyword(s):  
Laboratory Testing ◽  
Injection System ◽  
Cement Slurry ◽  
Element Analysis ◽  
Hydraulic Simulation ◽  
Novel Approach ◽  
Slurry System ◽  
Post Operation ◽  
Extended Reach Well ◽  
Fracture Gradient

Abstract Tailoring slurry designs using amorphous liquid silica base has been a success for Cementing Extended Reach Drilling (ERD) wells in Brunei in development fields. The use of this unconventional slurry density and design has helped to achieve the necessary top of cement and required zonal isolation for the production string of these wells. Cementing across depleted formations has been a challenge for the drilling sector within the oil industry. Isolation of production zones with competent cement slurries has become a necessity in fields, especially where a low Equivalent Circulating Density(ECD) during the cementing operation is required to achieve the desired top of cement in low fracture gradient formations. For Brunei offshore operations a novel approach has been proposed that uses an amorphous liquid silica-based slurry system to design a new 14 ppg lightweight cement slurry. The slurry properties were tailored to eliminate the need for a dual slurry system. Planning, execution, and post-operation evaluation methods have been developed for this new design. Extensive laboratory testing has been performed for the 14 ppg extended slurry which includes basic slurry testing as well as more advanced evaluations such as a full mechanical properties study and finite element analysis that was used compared to conventional slurry designs. Various optimizations were done for the slurry design to overcome mixability challenges and deployment using a conventional offshore liquid injection system or by premixing the water with liquid additives on a mixing tank or rig pits. To validate this technology, a field trial was performed at the rig site where a production liner for an extended reach well was cemented and subsequently evaluated using cement evaluation logging tools. The first Brunei offshore trial operation, executed in Q2 2020, was a 4.5-in. production liner where 16.5 m3 of a 14ppg novel slurry design was mixed, pumped and successfully placed within the annulus. Since the initial trial, a total of 8 jobs have been executed successfully in Brunei, with a few more wells identified as candidates for this solution. The paper provides laboratory testing details, hydraulic simulation validations along with job execution and post-operation cement evaluation.

scholarly journals Use of Dynamic Analysis to Investigate the Behaviour of Short Neutral Sections in the Overhead Line Electrification

2021 ◽  
Vol 6 (5) ◽  
pp. 62
Author(s):  
John Morris ◽  
Mark Robinson ◽  
Roberto Palacin
Keyword(s):  
Dynamic Analysis ◽  
Dynamic Simulation ◽  
Model Simulation ◽  
Analysis Tool ◽  
Overhead Line ◽  
Element Analysis ◽  
Novel Approach ◽  
Section Model ◽  
The Uk ◽  
Neutral Section

The ‘short’ neutral section is a feature of alternating current (AC) railway overhead line electrification that is often unreliable and a source of train delays. However hardly any dynamic analysis of its behaviour has been undertaken. This paper briefly describes the work undertaken investigating the possibility of modelling the behaviour using a novel approach. The potential for thus improving the performance of short neutral sections is evaluated, with particular reference to the UK situation. The analysis fundamentally used dynamic simulation of the pantograph and overhead contact line (OCL) interface, implemented using a proprietary finite element analysis tool. The neutral section model was constructed using physical characteristics and laboratory tests data, and was included in a validated pantograph/OCL simulation model. Simulation output of the neutral section behaviour has been validated satisfactorily against real line test data. Using this method the sensitivity of the neutral section performance in relation to particular parameters of its construction was examined. A limited number of parameter adjustments were studied, seeking potential improvements. One such improvement identified involved the additional inclusion of a lever arm at the trailing end of the neutral section. A novel application of pantograph/OCL dynamic simulation to modelling neutral section behaviour has been shown to be useful in assessing the modification of neutral section parameters.

Effect of Temperature, Reeling Speed and Pipe Tension on the Performance of Field Joint Coating During Reeling of Offshore Pipelines

2021 ◽  
Author(s):  
Rajaram Dhole ◽  
Ismael Ripoll ◽  
Sabesan Rajaratnam ◽  
Celine Jablonski
Keyword(s):  
Influential Factors ◽  
Influential Factor ◽  
Effect Of Temperature ◽  
Mechanical And Thermal Properties ◽  
Peak Strain ◽  
Element Analysis ◽  
Novel Approach ◽  
Laboratory Test Results ◽  
Coating Design ◽  
Highly Strained

Abstract Pipelines are coated with insulating material that minimizes heat losses to the environment. Reeled pipe can experience nominal bending strain in the order of 1% to 2%. Thick coating on the pipe is inherently more highly strained, because of concentrations that occur at the interface between parent coating and field joint coating. Occasionally, contractors who specialize in pipe-lay using the reeling method have experienced difficulties relating to unexpected disbondment and cracks in coating at these interfaces. Any disbonded coating is routinely identified and repaired, but it is important to understand the influential factors that could lead to this type of coating disbondment. It is known in the industry that parameters such as temperature, reeling speed and pipe tension are influential but the relative influence of the factors is not well understood. In addition, there is currently no industry code or recommended practice that proposes the strain levels that the coating could safely withstand prior to cracking. This paper addresses thermo-mechanical aspects of coating design and presents a novel approach to quantify which parameters have the largest influence. In the presented assessments, coating strain was assessed using finite element analysis. Material input was selected from a combination of typical values and specific laboratory test results for polypropylene (PP) and injection molded polypropylene (IMPP). An essential aspect was that the mechanical and thermal properties of the PP were related to temperature and strain rate. Strain rates in the coating during reeling operations were obtained from global FE models. Detailed local FE models incorporated all the material and load inputs and temperature conditions that are necessary to determine peak strain values in the coating; the peak strain values would indicate the locations of potential coating disbondment. The study is purely a strain assessment and excludes any potential for defects or delamination in the coating that could result from its manufacturing process. This strain-based study revealed that coating temperature during reeling is the most influential factor on strain level in the coating. Reeling speed and pipe tension are parameters providing secondary influences.

Use Of Fiber Materials to Mitigate Lost Circulation During Cementing Operations in Turkmenistan

2021 ◽  
Author(s):  
Amanmammet Bugrayev ◽  
Svetlana Nafikova ◽  
Salim Taoutaou ◽  
Guvanch Gurbanov ◽  
Maksatmyrat Hanov ◽  
...  
Keyword(s):  
Volume Fraction ◽  
Control Treatment ◽  
Cement Slurry ◽  
Lost Circulation ◽  
Innovative Materials ◽  
Primary Cementing ◽  
Fit For Purpose ◽  
Fiber Materials ◽  
Fracture Gradient ◽  
Application Requirements

Abstract Lost circulation in depleted sands during a primary cementing job is a serious problem in Turkmenistan. The uncertainty in formation pressure across these sands increases the risk of losses during drilling and cementing, which results in remedial operations and nonproductive time. The need to find a fit-for-purpose lost circulation solution becomes even more critical in an environment with narrow pore pressure-to-fracture gradient, where each cement job with losses compromises the downhole well integrity. An engineered lost circulation solution using innovative materials in the cement slurry was carefully assessed and qualified in the laboratory for each case to optimize the formulation. The lost circulation control treatment combines specialized engineered fibers with sized bridging materials to increase the effectiveness of treatment, formulated and added to the cement slurries based on the slurry solids volume fraction (SVF). Cement slurries with low SVF were treated with higher concentrations of the product and slurries with high SVF used lower concentrations. More than 50 jobs were performed with cement slurries designed at various densities and SVF up to 58% and using this advanced lost circulation material (LCM) to mitigate losses during cementing. Field experience showed positive results, where the differential pressure up to 2,800 psi was expected during cementing operation. A local database, generated based on the design and development work performed, enabled improved decision-making for selection and LCM application requirements for subsequent jobs and development of a lost circulation strategy. The mitigation plan was put in place against losses in critical sections and depleted sand formations in Turkmenistan. It assisted in meeting the cement coverage requirements on numerous occasions, improving overall the integrity of the wells and thus, was considered to be a success. This paper provides insight of this advanced LCM, its application in cement slurries, the logic behind the developed loss circulation strategy, and the high success rate of its implementation. Three case histories are presented to demonstrate the strategy and results.

Preparation of a high-temperature-resistant lightening agent and its application in a cement slurry system

2018 ◽  
Vol 136 (13) ◽  
pp. 47292 ◽  
Author(s):  
Rui Zhang ◽  
Qiong Han ◽  
Xuyang Zhu ◽  
Youfeng Cai ◽  
Tongqing Zhang
Keyword(s):  
High Temperature ◽  
Cement Slurry ◽  
Slurry System

Novel Surfactant for Spacer-Less Cementing Compatible with Non Aqueous Fluids

2021 ◽  
Author(s):  
Joseph K. Wee ◽  
Paulo Gomes ◽  
ShanShan Huang ◽  
Emmanuel Therond ◽  
Ansgar Heinrich, Dieker ◽  
...  
Keyword(s):  
Field Trial ◽  
Laboratory Testing ◽  
Scaling Up ◽  
Aqueous Fluid ◽  
Ionic Surfactant ◽  
Fluid Interface ◽  
Cement Slurry ◽  
Synthetic Oil ◽  
Operational Safety ◽  
Wet Surface

Abstract A novel, non-ionic surfactant is presented that alters typical cement incompatibility with non-aqueous fluids, effectively removing synthetic/oil-based mud (SOBM) from the wellbore and changing wettability of casing and formation from oil-wet to water-wet. The change in wettability eliminates the need for cement spacers conventionally deployed between the preceding non-aqueous fluid and the ensuing cement slurry. The entirety of spacer fluid interface can therefore be removed from operation, improving operational safety and efficiency, reduce waste and simplify wellsite logistics. The paper discusses the selection and evaluation of the proprietary surfactant in various laboratory testing. The main characteristics of the surfactant is its non-foaming, non-retarding, compatible with SOBM, ability to change oil-wet surface to water-wet, stable while minimizing environmentally impact. Scaling up, a yard test and a field trial in an offshore rig was successfully performed to evaluate the mixing, compatibility and pumpability using rig equipment.

Successful Single-Stage Cementing in a Weak Formation: A Case History in Spain

2014 ◽  
Author(s):  
A.. Bottiglieri ◽  
A.. Brandl ◽  
R.S.. S. Martin ◽  
R.. Nieto Prieto
Keyword(s):  
Engineering Design ◽  
Case History ◽  
Laboratory Testing ◽  
Single Stage ◽  
Formation Damage ◽  
Cement Slurry ◽  
Integrity Test ◽  
Open Hole ◽  
Zonal Isolation ◽  
Horizontal Wellbore

Abstract Cementing in wellbores with low fracture gradients can be challenging due to the risk of formation breakdowns when exceeding maximum allowable equivalent circulation densities (ECDs). Consequences include severe losses and formation damage, and insufficient placement of the cement slurry that necessitates time-consuming and costly remedial cementing to ensure zonal isolation. In recent cementing operations in Spain, the formation integrity test (FIT) of the open hole section indicated that the formation would have been broken down and losses occurred based on calculated equivalent circulating densities (ECDs) if the cement slurry had been pumped in a single-stage to achieve the operator's top-of-cement goal. As a solution to this problem, cementing was performed in stages, using specialty tools. However, during these operations, the stage tool did not work properly, wasting rig time and resulting in unsuccessful cement placement. To overcome this issue, the operator decided to cement the section in a single stage, preceded by a novel aqueous spacer system that aids in strengthening weak formations and controlling circulation losses. Before the operation, laboratory testing was conducted to ensure the spacer system's performance in weak, porous formations and better understand its mechanism. This paper will outline the laboratory testing, modeling and engineering design that preceded this successful single stage cementing job in a horizontal wellbore, with a final ECD calculated to be 0.12 g/cm3 (1.00 lb/gal) higher than the FIT-estimated figure.

Efficient J-Based Failure Assessment Diagrams for Engineering Critical Assessments of Circumferentially Cracked Pipes Subjected to Axial Force, Pressure, and Bending

2013 ◽  
Author(s):  
G. Graham Chell ◽  
Yi-Der Lee ◽  
Stephen J. Hudak
Keyword(s):  
Driving Forces ◽  
Material Behavior ◽  
Practical Implementation ◽  
Element Analysis ◽  
Strain Behavior ◽  
Axial Forces ◽  
Large Matrix ◽  
Novel Approach ◽  
Failure Assessment ◽  
Pipe Geometry

Engineering critical assessments (ECAs) of cracked pipes increasingly involve situations of high strains (e.g., reeling and ratcheting fatigue), multiple loads (combined bending, axial forces, and internal pressure), and multi-axial stressing (due to pressure). In this paper, some of the implications of these loading conditions on ECAs are investigated by generating BS 7910 Level 3C Failure Assessment Diagrams (FADs) from the results of a large matrix of finite element analysis (FEA) J computations for circumferentially cracked pipes. The Level 3C (J-based) FADs (which provide the most accurate FAD approach to ECAs) are compared with the corresponding and more widely employed (but less accurate) Level 2B (material dependent) FADs in order to assess the accuracy of the latter. Use of FEA J solutions in a Level 3C FAD ensures that the effects of material behavior, load type, crack type, crack geometry, and pipe geometry are accurately captured whereas a Level 2B FAD only attempts to accurately capture the effects of material stress-strain behavior. It is demonstrated that under some circumstances a Level 2B assessment will result in non-conservative results compared to the corresponding Level 3C assessment. The current comparison between Levels 3C and 2B addresses the mechanics involved in these approaches and does not take into account the possible differing treatments of material property uncertainties on ECAs within the two approaches. Based on the current results, an efficient J formulation is described that facilitates the practical implementation of a J-based ECA. The novel approach used is based on determining material dependent shift factors that transform Level 3C FADs derived from the fully plastic components of J solutions into Level 3C FADs that represent J behaviors in the linear elastic and fully plastic regimes, and the transition region in-between. This new J formulation treats combined axial forces, pressure, and bending when applied proportionally or non-proportionally and forms the basis of the monotonic and cyclic crack tip driving forces employed in the program FlawPRO. This program performs comprehensive conventional and high strain J-based ECAs that involve reeling, arbitrary strain cycling, ratcheting fatigue, and ductile tearing that are equivalent to a Level 3C FAD approach.

scholarly journals High Strain Survivability of Piezoceramics by Optimal Bonding Adhesive Design

Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2554 ◽  
Author(s):  
Hu Sun ◽  
Yishou Wang ◽  
Xinlin Qing ◽  
Zhanjun Wu
Keyword(s):  
Finite Element Analysis ◽  
Health Monitoring ◽  
Tensile Strain ◽  
High Strain ◽  
Aerospace Industry ◽  
Element Analysis ◽  
Strain Transfer ◽  
Impact Monitoring ◽  
Novel Approach ◽  
Host Structure

As one of the most common transducers used in structural health monitoring (SHM), piezoceramic sensors can play an important role in both damage detection and impact monitoring. However, the low tensile strain survivability of piezoceramics resulting from the material nature significantly limits their application on SHM in the aerospace industry. This paper proposes a novel approach to greatly improve the strain survivability of piezoceramics by optimal design of the adhesive used to bond them to the host structure. Theoretical model for determining the strain transfer coefficient through bonded adhesive from the host structure to piezoceramic is first established. Finite element analysis is then utilized to study the parameters of adhesive, including thickness and shear modulus. Experiments are finally conducted to validate the proposed method, and results show the piezoceramic sensors still work well when they are bonded on the host structures with tensile strain up to 4000 με by using the optimal adhesive.

Design of Oxidizer Referenced Fuel Pressure Regulator

2006 ◽  
Author(s):  
Tony Rousseau ◽  
Jonathan Terry ◽  
R. S. Amano
Keyword(s):  
Nitrous Oxide ◽  
Constant Pressure ◽  
Injection System ◽  
Cylinder Pressure ◽  
Reliable Operation ◽  
Pressure Regulator ◽  
Element Analysis ◽  
Critical Areas ◽  
Peak Cylinder Pressure ◽  
Fuel Source

This research involves the development and testing of a pressure regulator designed to maintain a constant pressure and mass flow relationship between the oxidizer and fuel source of a nitrous oxide injection system. Regulator design was accomplished through the exhaustive process of reviewing various fuel control and oxidizer referencing designs coupled with finite element analysis on the oxidizer referenced components to determine whether the selected components could handle the relatively high forces generated by the 1000psi nitrous oxide. The testing phase of the project was done in a dynamometer cell and involved numerous dynamometer tests of an engine supplied with a nitrous oxide kit both with and without the oxidizer referenced fuel pressure regulator. These tests monitored critical areas such as peak cylinder pressure, the location of the peak cylinder pressure, the air/fuel ratio, the nitrous oxide bottle pressure, and the knock intensity. The data collected in each of these areas was used to compare the performance of a regulated and non-regulated system as well as ensure the safe and reliable operation of the engine.

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