Feasibility Analysis for Repair of Large Diameter Hydro Turbine Shaft Based on Weldability Test and Welding Cycle Simulation

2019 ◽  
Vol 1153 ◽  
pp. 36-45
Author(s):  
Dejan Momčilović ◽  
Zoran Odanović
Keyword(s):  
Failure Analysis ◽  
Good Practice ◽  
Large Diameter ◽  
Indirect Costs ◽  
Operating Conditions ◽  
Feasibility Analysis ◽  
Hydro Turbine ◽  
Cycle Simulation ◽  
Alloy Heat ◽  
The Right

Turbine and generator rotors and shafts undergo high stresses during regular working life and, from a safety and operational aspect, are the most significant components of a power generation system. Depending on the appropriate operating conditions, like temperature and/or corrosion the, shafts can be fabricated out of low/high alloy heat resistance material or of low alloyed, highly toughened material for different application. Despite known good practice and developed operation procedures, the failures of shafts sometimes occur. The right and well-defined failure analysis is the basis for feasibility analysis of repair method in the power generating industry. The analysis of direct and indirect costs of repair after the failure analysis as well as the analysis of the repair and post-repair conditions of the repaired element is the vital for decision on the key question. Is it possible to repair this element and what is the optimal repair strategy? This paper compares and analyses two approaches, by weldability analysis and weld cycle simulation, in order to determine welding feasibility analysis of cracked hydro turbine shafts.

scholarly journals Cost-effective ultrasonic inspection of large diameter pipelines

2020 ◽  
Vol 4 (2) ◽  
pp. 108-116
Author(s):  
Ries Augustijn ◽  
◽  
João Gonçalves ◽  
Joost Haaksman ◽  
◽  
...  
Keyword(s):  
High Resolution ◽  
Large Diameter ◽  
Ultrasonic Inspection ◽  
Real Life ◽  
Cost Effective ◽  
Operating Conditions ◽  
Limiting Factor ◽  
Technological Capabilities ◽  
High Salinity Water ◽  
The Right

To be successful in the ILI business, organization require the right mix of technological capabilities, operational agility and quality standards. The business is fairly competitive, and often technological capabilities are pivotal in the customer proposition of the company. However, the best technologies are not solely required for successful ILI companies. Robustness of the system, operability by the ILI inspector, fitness of the product with commercial route to the market all contribute to a rapid return on investment. Providing a robust, versatile, high-resolution and cost-effective method to inspect large diameter pipelines was recognized as a challenge and opportunity. For that, a Large Diameter Ultrasonic Inspection tool capable of inspecting pipelines of 20 inch to 64 inch with high resolution was developed. The tool is always bi-directional and capable of mitigating 1.5D bends. Gathered data can be reviewed real-time during the inspection. The operating envelope of the tool is such that it can cope with various products in the pipeline, varying from (high salinity) water, crude oil and a multitude of refined products. Despite the fact that product properties (e.g. speed of sound, attenuation, temperature, etc) vary, the tool is designed such that this is not a limiting factor for the operating envelope. The application of advanced ultrasonic beam forming methodologies and signal generation and -processing ensure that the system is versatile and robust for these types of real-life operating conditions. This presentation will provide an overview of the utilization of these technologies, the validation program that has been used to demonstrate tool specifications and the experiences gained at successful projects.

Process Induced Defects in the Silicon Substrate: Approaches for Successful Failure Analysis

2010 ◽  
Author(s):  
J.G. van Hassel ◽  
Xiao-Mei Zhang
Keyword(s):  
Failure Analysis ◽  
Case Studies ◽  
Silicon Substrate ◽  
Processing Technique ◽  
Electrical Characteristics ◽  
Localization Method ◽  
The Right ◽  
Induced Defects

Abstract Failures induced in the silicon substrate by process marginalities or process mistakes need continuous attention in new as well as established technologies. Several case studies showing implant related defects and dislocations in silicon will be discussed. Depending on the electrical characteristics of the failure the localization method has to be chosen. The emphasis of the discussion will be on the importance of the right choice for further physical de-processing to reveal the defect. This paper focuses on the localization method, the de- processing technique and the use of Wright etch for subsequent TEM preparation.

Pseudo-Dynamic Fault Isolation Technique Using Backside Emission Microscopy – Case Study, Where All Other Methods Fail

2002 ◽  
Author(s):  
Yoav Weizman ◽  
Ezra Baruch ◽  
Michael Zimin
Keyword(s):  
Failure Analysis ◽  
Process Variations ◽  
Fault Isolation ◽  
Operating Conditions ◽  
Detection Sensitivity ◽  
Isolation Technique ◽  
Root Cause ◽  
Emission Microscopy ◽  
Failure Location ◽  
Noisy Background

Abstract Emission microscopy is usually implemented for static operating conditions of the DUT. Under dynamic operation it is nearly impossible to identify a failure out of the noisy background. In this paper we describe a simple technique that could be used in cases where the temporal location of the failure was identified however the physical location is not known or partially known. The technique was originally introduced to investigate IDDq failures (1) in order to investigate timing related issues with automated tester equipment. Ishii et al (2) improved the technique and coupled an emission microscope to the tester for functional failure analysis of DRAMs and logic LSIs. Using consecutive step-by-step tester halting coupled to a sensitive emission microscope, one is able detect the failure while it occurs. We will describe a failure analysis case in which marginal design and process variations combined to create contention at certain logic states. Since the failure occurred arbitrarily, the use of the traditional LVP, that requires a stable failure, misled the analysts. Furthermore, even if we used advanced tools as PICA, which was actually designed to locate such failures, we believe that there would have been little chance of observing the failure since the failure appeared only below 1.3V where the PICA tool has diminished photon detection sensitivity. For this case the step-by-step halting technique helped to isolate the failure location after a short round of measurements. With the use of logic simulations, the root cause of the failure was clear once the failing gate was known.

scholarly journals A New Method to Determine the Impact of Individual Field Quantities on Cycle-to-Cycle Variations in a Spark-Ignited Gas Engine

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4136
Author(s):  
Clemens Gößnitzer ◽  
Shawn Givler
Keyword(s):  
Kinetic Energy ◽  
Flow Field ◽  
Turbulent Kinetic Energy ◽  
Negative Impact ◽  
Operating Conditions ◽  
Engine Operation ◽  
Gas Engine ◽  
Cycle Simulation ◽  
Simulation Results ◽  
The Impact

Cycle-to-cycle variations (CCV) in spark-ignited (SI) engines impose performance limitations and in the extreme limit can lead to very strong, potentially damaging cycles. Thus, CCV force sub-optimal engine operating conditions. A deeper understanding of CCV is key to enabling control strategies, improving engine design and reducing the negative impact of CCV on engine operation. This paper presents a new simulation strategy which allows investigation of the impact of individual physical quantities (e.g., flow field or turbulence quantities) on CCV separately. As a first step, multi-cycle unsteady Reynolds-averaged Navier–Stokes (uRANS) computational fluid dynamics (CFD) simulations of a spark-ignited natural gas engine are performed. For each cycle, simulation results just prior to each spark timing are taken. Next, simulation results from different cycles are combined: one quantity, e.g., the flow field, is extracted from a snapshot of one given cycle, and all other quantities are taken from a snapshot from a different cycle. Such a combination yields a new snapshot. With the combined snapshot, the simulation is continued until the end of combustion. The results obtained with combined snapshots show that the velocity field seems to have the highest impact on CCV. Turbulence intensity, quantified by the turbulent kinetic energy and turbulent kinetic energy dissipation rate, has a similar value for all snapshots. Thus, their impact on CCV is small compared to the flow field. This novel methodology is very flexible and allows investigation of the sources of CCV which have been difficult to investigate in the past.

scholarly journals Managing energy performance in buildings from design to operation using modelling and calibration

2021 ◽  
pp. 014362442110083
Author(s):  
Nishesh Jain ◽  
Esfand Burman ◽  
Dejan Mumovic ◽  
Mike Davies
Keyword(s):  
Best Practice ◽  
Good Practice ◽  
Energy Performance ◽  
Operating Conditions ◽  
Design Stage ◽  
Performance Gap ◽  
Actual Performance ◽  
Simulation Tools ◽  
Calibration Protocol ◽  
Covering Design

To manage the concerns regarding the energy performance gap in buildings, a structured and longitudinal performance assessment of buildings, covering design through to operation, is necessary. Modelling can form an integral part of this process by ensuring that a good practice design stage modelling is followed by an ongoing evaluation of operational stage performance using a robust calibration protocol. In this paper, we demonstrate, via a case study of an office building, how a good practice design stage model can be fine-tuned for operational stage using a new framework that helps validate the causes for deviations of actual performance from design intents. This paper maps the modelling based process of tracking building performance from design to operation, identifying the various types of performance gaps. Further, during the operational stage, the framework provides a systematic way to separate the effect of (i) operating conditions that are driven by the building’s actual function and occupancy as compared with the design assumptions, and (ii) the effect of potential technical issues that cause underperformance. As the identification of issues is based on energy modelling, the process requires use of advanced and well-documented simulation tools. The paper concludes with providing an outline of the software platform requirements needed to generate robust design models and their calibration for operational performance assessments. Practical application The paper’s findings are a useful guide for building industry professionals to manage the performance gap with appropriate accuracy through a robust methodology in an easy to use workflow. The methodological framework to analyse building energy performance in-use links best practice design stage modelling guidance with a robust operational stage investigation. It helps designers, contractors, building managers and other stakeholders with an understanding of procedures to follow to undertake an effective measurement and verification exercise.

scholarly journals Diagnostic and Therapeutic Performance of Video-Assisted Thoracoscopic Surgery (Vats) in Investigation and Management of Pleural Exudates

2008 ◽  
Vol 90 (7) ◽  
pp. 597-600 ◽  
Author(s):  
ARL Medford ◽  
YM Awan ◽  
A Marchbank ◽  
J Rahamim ◽  
J Unsworth-White ◽  
...  
Keyword(s):  
Diagnostic Yield ◽  
Thoracoscopic Surgery ◽  
Good Practice ◽  
National Standards ◽  
Postoperative Fever ◽  
Video Assisted ◽  
The Right ◽  
Culture Negative ◽  
Video Assisted Thoracoscopic Surgery ◽  
Fluid Culture

INTRODUCTION Video-assisted thoracoscopic surgery (VATS) is the gold standard investigation for diagnosis of pleural exudates. It is invasive and it is important to ensure that it is performed to acceptable national standards. We assumed that VATS empyema fluid culture would not contribute further to microbiological diagnosis in referred culture-negative empyemas. PATIENTS AND METHODS Eighty-six consecutive external referrals for VATS for diagnosis of a cytology-negative pleural exudate (or for further management of the exudate) were studied retrospectively. Diagnostic yield, pleurodesis efficacy and complications were compared to national standards and good practice recommendations. VATS empyema fluid microbiological culture results were compared to pre-VATS empyema fluid culture results. RESULTS VATS was performed well within national standards with a diagnostic yield of 82.3% for cytology-negative exudates, 100% pleurodesis efficacy, 5.8% postoperative fever, with only one significant complication (1.2% rate) and no deaths. Compliance with good practice pleural fluid documentation points was greater than 70%. VATS empyema fluid culture positivity (84.6%) was significantly higher than pre-VATS fluid culture (35%). CONCLUSIONS VATS was performed to acceptable standards. These data confirm the utility and safety of VATS in the right context but also suggest the potential diagnostic utility of VATS empyema fluid culture. Further studies are required to investigate this latter possibility further.

Access and Logistics Challenges in Mountain Terrain Pipeline Projects

2014 ◽  
Author(s):  
Mark McDougall ◽  
Ken Williamson
Keyword(s):  
Construction Projects ◽  
Large Scale ◽  
Oil And Gas ◽  
Large Diameter ◽  
Gas Production ◽  
Additional Time ◽  
Oil And Gas Production ◽  
Road Design ◽  
Regulatory Constraints ◽  
The Right

Oil and gas production in Canada’s west has led to the need for a significant increase in pipeline capacity to reach export markets. Current proposals from major oil and gas transportation companies include numerous large diameter pipelines across the Rocky Mountains to port locations on the coast of British Columbia (BC), Canada. The large scale of these projects and the rugged terrain they cross lead to numerous challenges not typically faced with conventional cross-country pipelines across the plains. The logistics and access challenges faced by these mountain pipeline projects require significant pre-planning and assessment, to determine the timing, cost, regulatory and environmental impacts. The logistics of pipeline construction projects mainly encompasses the transportation of pipe and pipeline materials, construction equipment and supplies, and personnel from point of manufacture or point of supply to the right-of-way (ROW) or construction area. These logistics movement revolve around the available types of access routes and seasonal constraints. Pipeline contractors and logistics companies have vast experience in moving this type of large equipment, however regulatory constraints and environmental restrictions in some locations will lead to significant pre-planning, permitting and additional time and cost for material movement. In addition, seasonal constraints limit available transportation windows. The types of access vary greatly in mountain pipeline projects. In BC, the majority of off-highway roads and bridges were originally constructed for the forestry industry, which transports logs downhill whereas the pipeline industry transports large equipment and pipeline materials in both directions and specifically hauls pipe uphill. The capacity, current state and location of these off-highway roads must be assessed very early in the process to determine viability and/or potential options for construction access. Regulatory requirements, environmental restrictions, season of use restrictions and road design must all be considered when examining the use of or upgrade of existing access roads and bridges. These same restrictions are even more critical to the construction of new access roads and bridges. The logistics and access challenges facing the construction of large diameter mountain pipelines in Western Canada can be managed with proper and timely planning. The cost of the logistics and access required for construction of these proposed pipeline projects will typically be greater than for traditional pipelines, but the key constraint is the considerable time requirement to construct the required new access and pre-position the appropriate material to meet the construction schedule. The entire project team, including design engineers, construction and logistics planners, and material suppliers must be involved in the planning stages to ensure a cohesive strategy and schedule. This paper will present the typical challenges faced in access and logistics for large diameter mountain pipelines, and a process for developing a comprehensive plan for their execution.

Respecting care home residents’ right to privacy: what is the evidence of good practice?

2018 ◽  
Vol 22 (4) ◽  
pp. 198-210 ◽  
Author(s):  
Caroline Emmer De Albuquerque Green ◽  
Anthea Tinker ◽  
Jill Manthorpe
Keyword(s):  
Literature Review ◽  
Care Home ◽  
Good Practice ◽  
Physical Space ◽  
Personal Data ◽  
Care Homes ◽  
Right To Privacy ◽  
Human Right ◽  
Content Type ◽  
The Right

Purpose The purpose of this paper is to review and discuss evidence of good practice in respecting care home residents’ right to privacy. The right to privacy is a fundamental human right as enshrined in international and domestic law and standards. In the context of increasing interest in using a human rights approach to social care in care homes for older people, this literature review summarises research evidence on what respecting the human right to privacy of care home residents entails in practice. Design/methodology/approach This literature review followed a rigorous systematic approach to the scoping review, inspired by the Joanna Biggs Institute’s guidelines for conducting systematic reviews. A total of 12 articles were included in the review. Findings The research took a multidimensional understanding of privacy in their studies. The dimensions can be categorised as physical, inter-relational or related to personal data. The review highlights three good practice points. First, it is good privacy practice in care homes to make available single-occupancy bedrooms to residents since this offers the opportunity to personalising this physical space with furniture and web belongings, adding a sense of ownership over the space. Second, residents appreciate being able to choose when and how they spend their time in their own bedrooms. Third, it is good practice to respect residents’ private physical space and private choices, for example by knocking on doors before entering or agreeing with the resident when it is permissible to enter. The review also found that in some studies privacy considerations were relevant to communal living areas within care homes, including the use of surveillance cameras and the sharing of personal data. Originality/value This literature review adds to the body of academic literature on human rights and social care in practice. It also highlights areas for future research relating to the right to privacy in care homes.

scholarly journals Folded large-bore central catheter in the right internal jugular vein as shown by ultrasound: a case report

2018 ◽  
Vol 47 (2) ◽  
pp. 1005-1009
Author(s):  
Taehee Pyeon ◽  
Jeong-Yeon Hwang ◽  
HyungYoun Gong ◽  
Sang-Hyun Kwak ◽  
Joungmin Kim
Keyword(s):  
Central Venous Catheter ◽  
Internal Jugular Vein ◽  
Jugular Vein ◽  
Present Report ◽  
Large Diameter ◽  
Venous Catheter ◽  
Venous Access ◽  
Central Venous ◽  
The Right ◽  
Gain Access

Central venous catheters are used for various purposes in the operating room. Generally, the use of ultrasound to insert a central venous catheter is rapid and minimally complicated. An advanced venous access (AVA) catheter is used to gain access to the pulmonary artery and facilitate fluid resuscitation through the internal jugular vein. The present report describes a case in which ultrasound was used in a 43-year-old man to avoid complications during insertion of an AVA catheter with a relatively large diameter. The sheath of the catheter was so thin that a dilator was essential to prevent it from folding upon insertion. Despite the use of ultrasound guidance, the AVA catheter sheath became folded within the patient’s internal jugular vein. Mechanical complications of central venous catheter insertion are well known, but folding of a large-bore catheter in the internal jugular vein has rarely been reported.

Anaphylactic shock: are we doing enough and with the right timing and order?

2015 ◽  
Vol 53 (3) ◽  
pp. 191-198
Author(s):  
H. Bălan ◽  
Adriana Gurghean
Keyword(s):  
Anaphylactic Shock ◽  
Good Practice ◽  
Fluid Replacement ◽  
First Line ◽  
Good Opportunity ◽  
First Line Therapy ◽  
Line Therapy ◽  
Practice Parameters ◽  
Golden Standard ◽  
The Right

Abstract Anaphylactic shock became, unfortunately, a common presence in Romanian mass-media, due to some fatal cases in the last months. The coincidence that in December 2014 the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology, and the Joint Council of Allergy Asthma and Immunology released Practice parameters offers a good opportunity to renew for all practitioners what is now considered the “golden standard” of good practice. Epinephrine must be considered the cornerstone and the most urgent measure to be applied in these cases, immediately after the diagnosis. A very important notice is to forget the administration of antihistamines or corticosteroids as first line therapy instead of epinephrine. Proper positioning of the subjects and quick fluid replacement (1-2 l of normal saline in a few minutes) are also mandatory.

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