A New Approach To Drill-String Acoustic Telemetry

1979 ◽  
Author(s):  
William D. Squire ◽  
H.J. Whitehouse
Keyword(s):  
Acoustic Telemetry ◽  
Drill String ◽  
New Approach

Dynamic Drill-string Modeling for Acoustic Telemetry

2022 ◽  
pp. 107043
Author(s):  
Hamid Mostaghimi ◽  
Jediael R. Pagtalunan ◽  
Bryan Moon ◽  
Seonghwan Kim ◽  
Simon S. Park
Keyword(s):  
Acoustic Telemetry ◽  
Drill String

scholarly journals Optimal drill string design for acoustic borehole communication

2021 ◽  
Vol 8 (11) ◽  
pp. 96-103
Author(s):  
Ali H. Alenezi ◽  
Keyword(s):  
Acoustic Telemetry ◽  
Communication Channel ◽  
Channel Model ◽  
Data Transfer ◽  
Small Deviation ◽  
Drill String ◽  
Channel Bandwidth ◽  
Drilling Operations ◽  
Main Components

The acoustic telemetry used the drill string as a communication channel, which allows data transfer without interrupting drilling operations. This technology suffers from stop-bands that reduce the feasible bands for transmission up to 60 percent. The stop bands come due to the structure of the drill string constructed from pipes and tool joints. In this paper, we optimized the design of the drill string main components, which are pipes and tool-joints lengths, with an aim to increase the pass-bands total bandwidth. Using the verified drill string channel model, we proved that, with optimal lengths of pipes and tool joints, we can make the whole drill string channel bandwidth available for transmission. We also investigated the effect of small deviation from the optimal lengths on the channel transmission bands. The results showed that an increase of more than 138 percent in the available transmission bandwidths compared with standard drill string dimensions.

scholarly journals A hybrid model for a drilling process for hydrocarbon well-boring operations

2017 ◽  
Vol 231 (4) ◽  
pp. 726-738
Author(s):  
MYA Alkaragoolee ◽  
KM Ebrahimi ◽  
R Whalley
Keyword(s):  
Drill String ◽  
Drilling Process ◽  
Stick Slip ◽  
Well Drilling ◽  
Hybrid Modelling ◽  
New Approach ◽  
Modelling Method ◽  
Drilling Equipment ◽  
Equipment Failures ◽  
Drilling Operations

In hydrocarbon well-drilling operations, self-excited, stick-slip vibration is considered as a source of drilling equipment failures, which also causes a reduction in the drilling penetration. This leads to delays and increase in the operational and equipment costs. A new approach using distributed-lumped (hybrid) modelling is considered as the first step in understanding the stick-slip phenomena in order to determine a solution to this problem. In this paper, a hybrid modelling scheme is the advocated modelling method proposed in contrast to the conventional lumped modelling. Three case studies are used to show that hybrid modelling is an accurate technique in the representation of stick-slip oscillations, particularly when the length of the drill string is high. The results show that the modelling technique adopted in this work can more accurately present the phenomena associated with stick-slip process.

A New Down Hole Tool and Approach To Release Differentially Stuck Pipe

2021 ◽  
Author(s):  
Krzysztof Karol Machocki ◽  
Abdulwahab Aljohar ◽  
David Zhan ◽  
Ayodeji Abegunde
Keyword(s):  
System Design ◽  
System Integration ◽  
New Technology ◽  
Drill String ◽  
Design Features ◽  
New Approach ◽  
Lateral Forces ◽  
Bottom Hole ◽  
Bottom Hole Assembly ◽  
New System

Abstract A new down hole system and method to use for releasing stuck pipes is presented. New system design, features and limits are compared to commonly used techniques for releasing stuck pipe showing benefits of the new system when dealing with differential stuck pipe incidents. The new down hole system is capable to deliver much greater forces when compared to jars and other down hole accelerators near the stuck point. This system can generate over 40G`s lateral forces continuously down the hole acting on the stuck pipe area. The system can be integrated into a Bottom Hole Assembly (BHA) and activated once drill string become stuck or run as a part of the remediate assembly. Different aspects of two types of assemblies are described outlining the benefits and drawbacks. The author will discuss in details the background and rationale to the new technology, including a review of differential sticking challenges and functionality of this new system. The new system was compared to the most commonly used techniques for releasing differentially stuck pipe. Previously not releasable stuck pipe forces of over 1,000,000 lb. can now be overcome with the presented new approach to generate down hole forces near the stuck place. Flexibility in system integration and deployment allows for further optimization in BHA design and cost affective fishing operations in dedicated hole sections. This new approach can be implemented to release the most challenging stuck pipe mechanisms in drilling to minimize NPT and cost associated with stuck pipe, remedial operations and sidetracks. Similar approach can be utilized to release differentially stuck pipes, tubing and completions. The novelty of this stuck pipe release system is the entire down hole system and operations of the overall system using new approach to generate large shocks down the hole. Additional novelty is related to flexibility during integration and deployment of this system. Similar to current shock tools, this system can be placed in BHA, fishing type assemblies and also pumped down inside of the stuck drill string to save time and cost.

New Approach to Linear and Nonlinear Stability Analysis of Drill String

2010 ◽  
Author(s):  
Ali Asghar Jafari ◽  
Reza Kazemi ◽  
Mohammad Faraji Mahyari
Keyword(s):  
Stability Analysis ◽  
Potential Energy ◽  
Nonlinear Stability ◽  
Equilibrium Position ◽  
Continuous System ◽  
Drill String ◽  
Order Derivative ◽  
Nonlinear Stability Analysis ◽  
New Approach ◽  
Linear And Nonlinear

In this research, a new approach for stability analysis of drill string is investigated. To this goal, the potential energy of drill string for axial and lateral vibrations is written in an integral equation. In this equation, the effect of geometrical shortening, which causes nonlinear coupling between axial and lateral vibration, is considered. The work done by WOB force and weight of drill string is calculated. The finite element method is employed to convert the integral potential energy of the continuous system to a discrete one. The effects of stabilizers are modeled by dropping the nodes coincided with them. Dropping and considering third and fourth order tensor of potential energy lead to linear and nonlinear stability analysis, respectively. Taking the first order derivative of discrete potential energy, the equilibrium position of drill string can be found. Taking second order derivative, the stability of the equilibrium position can be analyzed. Illustrated results demonstrate that as the length of hole is increased, the differences between linear and nonlinear cases become larger. This analysis shows the working condition of drill string is stable or not. These results can be used to obtain safe working conditions in drilling progress.

The O–C diagrams of minor planets − a new approach to modelling the rotation

1999 ◽  
Vol 173 ◽  
pp. 185-188
Author(s):  
Gy. Szabó ◽  
K. Sárneczky ◽  
L.L. Kiss
Keyword(s):  
Error Analysis ◽  
Time Dependence ◽  
Theoretical Work ◽  
Minor Planet ◽  
Minor Planets ◽  
New Approach ◽  
Preliminary Results ◽  
Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Processing Immunoperoxidase Labeled Cell Monolayers and Cryostat Sesctions For Electron Microscopy

1985 ◽  
Vol 43 ◽  
pp. 714-715
Author(s):  
K. Chien ◽  
R. Van de Velde ◽  
I.P. Shintaku ◽  
A.F. Sassoon
Keyword(s):  
Cell Monolayer ◽  
Cell Types ◽  
Surface Antigens ◽  
Immunoperoxidase Method ◽  
Reaction Step ◽  
Hot Plate ◽  
Air Drying ◽  
New Approach ◽  
Cell Monolayers ◽  
Glass Slides

Immunoelectron microscopy of neoplastic lymphoma cells is valuable for precise localization of surface antigens and identification of cell types. We have developed a new approach in which the immunohistochemical staining can be evaluated prior to embedding for EM and desired area subsequently selected for ultrathin sectioning.A freshly prepared lymphoma cell suspension is spun onto polylysine hydrobromide- coated glass slides by cytocentrifugation and immediately fixed without air drying in polylysine paraformaldehyde (PLP) fixative. After rinsing in PBS, slides are stained by a 3-step immunoperoxidase method. Cell monolayer is then fixed in buffered 3% glutaraldehyde prior to DAB reaction. After the DAB reaction step, wet monolayers can be examined under LM for presence of brown reaction product and selected monolayers then processed by routine methods for EM and embedded with the Chien Re-embedding Mold. After the polymerization, the epoxy blocks are easily separated from the glass slides by heatingon a 100°C hot plate for 20 seconds.

TEM study of a biofilm on copper corrosion

1996 ◽  
Vol 54 ◽  
pp. 220-221
Author(s):  
W. A. Chiou ◽  
N. Kohyama ◽  
B. Little ◽  
P. Wagner ◽  
M. Meshii
Keyword(s):  
Marine Bacterium ◽  
Culture Medium ◽  
Copper Alloys ◽  
Pure Copper ◽  
Localized Corrosion ◽  
Natural Seawater ◽  
Copper Corrosion ◽  
New Approach ◽  
The Past ◽  
Copper Tolerant

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

High resolution at low voltage: A new approach

1989 ◽  
Vol 47 ◽  
pp. 76-77
Author(s):  
Arthur V. Jones
Keyword(s):  
Low Voltage ◽  
Emission Sources ◽  
New Approach ◽  
Design Concepts ◽  
Probe Diameter ◽  
Low Voltage Operation ◽  
Sufficient Intensity ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Immersion Type

With the introduction of field-emission sources and “immersion-type” objective lenses, the resolution obtainable with modern scanning electron microscopes is approaching that obtainable in STEM and TEM-but only with specific types of specimens. Bulk specimens still suffer from the restrictions imposed by internal scattering and the need to be conducting. Advances in coating techniques have largely overcome these problems but for a sizeable body of specimens, the restrictions imposed by coating are unacceptable.For such specimens, low voltage operation, with its low beam penetration and freedom from charging artifacts, is the method of choice.Unfortunately the technical dificulties in producing an electron beam sufficiently small and of sufficient intensity are considerably greater at low beam energies — so much so that a radical reevaluation of convential design concepts is needed.The probe diameter is usually given by

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