catastrophic failures
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Author(s):  
Efe Peter Iyomi

Abstract: The proactive maintenance of pipelines through condition based monitoring, plays an essential role in improving their overall reliability and availability. Their criticality can also be assessed by conducting reliability analysis such as FMECA, which helps in identifying relevant failure modes and averting catastrophic failures to sustain economic growth. This paper will focus on an integrity assessment set up for pipelines and the potential failure modes associated are evaluated and mitigated by determining the risk triggers. The outcome of this research has shown the various threats associated with pipelines, having an effective integrity assessment program will help mitigate such threats. Keywords: Risk Assessment, Corrosion, FMECA, Risk Priority, Failure, Inspection, Regulations, Pipelines, Monitoring


Electronics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 48
Author(s):  
Wei Zhong ◽  
Thomas Walther

The failure mechanism of two commercial light-emitting diode (LED)-based spotlights with GU10 form factor is analyzed. Through component testing and comparison to nominal values as well as to simulations, it is found that the cause of both device failures is related to damaged components within the drive circuits rather than the LEDs themselves. Both LED heads work as normal when connected to an external direct current (DC) source. The results show that the lack of light output of one spotlight is related to the open circuit caused by damaged resistors and inductors in its drive circuit, while the flickering of the other is related to the malfunction of the integrated circuit providing constant current output. Therefore, improving the quality of the LED drive circuits is considered the most effective way for manufacturers to reduce catastrophic failures of LED spotlights.


2021 ◽  
Vol 11 (24) ◽  
pp. 12046
Author(s):  
Tibor Skala ◽  
Mirsad Todorovac ◽  
Miklós Kozlovszky ◽  
Marko Maričević

In this paper, we describe the challenge of developing a web front that will give an interactive and relatively immediate result without the overhead of complex grid scheduling, in the sense of the grid’s lack of interactivity and need for certificates that users simply do not own. In particular, the local system of issuing grid certificates is somewhat limited to a narrower community compared to that which we wanted to reach in order to popularize the grid, and our desired level of service availability exceeded the use of the cluster for grid purposes. Therefore, we have developed an interactive, scalable web front and back-end animation rendering frame dispatcher to access our cluster’s rendering power with low latency, low overhead and low performance penalty added to the cost of Persistence of Vision Ray rendering. The system is designed to survive temporary or catastrophic failures such as temporary power loss, load shedding, malfunction of rendering server cluster or client hardware, whether through an automatic or a manual restart, as long as the hardware that keeps the previous work and periodically dumped state of the automata is preserved.


2021 ◽  
Vol 2090 (1) ◽  
pp. 012112
Author(s):  
M Krol

Abstract Considering constant development of the interior ballistics, along with new gun and ammunition designs, the necessity of in-depth analysis of the shot event is continuously increasing. Numerical simulations of interior ballistics problems are useful for optimising new designs or explaining complex issues, regarding performance instabilities and catastrophic failures. With the rise of the computing power, there is a significant urge to drive the numerical errors towards machine zero. This goal demands using methods of high order of accuracy in both space and time. Current methods allow to achieve an arbitrary order of numerical accuracy, thus allowing to shift the focus towards sophistication of the mathematical model of the studied phenomenon. Therefore, in this work, some numerical schemes, in context of finite volume method, are reviewed and studied using well established test problems. The results of the presented analysis are meant to become the basis for future development of a high order numerical scheme for simulation of interior ballistics problems.


2021 ◽  
Vol 2089 (1) ◽  
pp. 012076
Author(s):  
A Indra Reddy ◽  
K V Ramana

Abstract Predictive maintenance is also known as condition monitoring. It is a technique in which systems are monitored at various key points of the operating machinery and data is observed. Analyzing the data is very much useful to assess the health of the machine thereby catastrophic failures can be avoided. This leads to more production and also eliminate to a great extent, the inventory. To make the technique more convenient, the expert system is very much useful. In this paper an attempt has been made to take up a comprehensive review of the literature and emphasis has been given to lubricant condition-based monitoring through an expert system, which will spell out the probable faults along with remedial measures. The expert system embeds the viscosity of lubricant as measurand. It has been developed for different grades of lubricating oils and their industrial utility.


2021 ◽  
Vol 21 (2/3) ◽  
pp. 989-1005
Author(s):  
Rae Rosario Stevenson ◽  
Joan M. Blakey

In its current form, the field of social work does not reflect the ongoing reality of Black death and the embeddedness of anti-Blackness in everyday life. This omission leads to catastrophic failures of the profession’s most essential tasks: the advancement of social justice and future social workers’ education. This paper will discuss why the police’s ongoing murder of Black people will not be resolved by simply replacing the police with social workers. We will argue that social workers serving Black people must anchor their work in theoretical perspectives articulated by Black people. Finally, we challenge social work to live up to its social justice mission by divesting from systems of social control and anchoring their work in theoretical perspectives articulated by Black people.


2021 ◽  
Author(s):  
Krzysztof Karol Machocki ◽  
Zahrah Marhoon ◽  
Amjad Shaarawi ◽  
Ossama Sehsah ◽  
Tom Dixon ◽  
...  

Abstract Managed pressure drilling (MPD) is a technology that allows for precise wellbore pressure control, especially in formations of uncertain geomechanical properties (in specific: Fracture pressure and pore pressure gradients). The rotating control device (RCD) is the backbone to the MPD equipment. A new condition monitoring system was developed to improve the reliability of the RCD elements and to eliminate its catastrophic failures during MPD jobs. The new method to increase the reliability of an RCD is based on understanding and quantifying the factors affecting the lifetime of the RCD components. The condition monitoring system was designed to be attached onto the RCD and collect data from an array of sensors during the MPD jobs. Sensors are measuring: vibrations, acoustic emissions, rotation, pipe movement, temperatures and contamination level in the coolant fluid. System is capable to display the measurements in the real time to the operator, giving early warnings to take actions in order to prevent catastrophic failures of the RCD during the job. Data is also recorded to allow further processing and analysis using ML and AI techniques. The authors will discuss in detail the background and rationale to the new technology, including a review of the condition monitoring system, its elements, and functionality. The system design and intended operation will be explained including, sensors and data collection points in the condition monitoring process. No catastrophic failures of the RCD were encountered when the RCD condition monitoring system was installed and running in the field up to date. The measurements collected from the array of sensors and presented in the real time to the MPD operators, allows to monitor changes in condition of the critical RCD elements. From the system design, sensor type, and frequency of data inputs, it was concluded that the quantification of some parameters affecting the lifetime of RCD could be successfully performed in post analysis, using advanced AI techniques. This condition monitoring system can optimize the MPD operations, making MPD jobs safer and reducing the Non Productive Time. The novelty of this condition monitoring system is in the approach of measuring and displaying critical values to the operator during the job and possibility to quantification of the factors affecting the RCD elements lifetime.


2021 ◽  
pp. 51-68
Author(s):  
Daniel J. Benac

Abstract Life assessment of structural components is used to avoid catastrophic failures and to maintain safe and reliable functioning of equipment. The failure investigator's input is essential for the meaningful life assessment of structural components. This article provides an overview of the structural design process, the failure analysis process, the failure investigator's role, and how failure analysis of structural components integrates into the determination of remaining life, fitness-for-service, and other life assessment concerns. The topics discussed include industry perspectives on failure and life assessment of components, structural design philosophies, the role of the failure analyst in life assessment, and the role of nondestructive inspection. They also cover fatigue life assessment, elevated-temperature life assessment, fitness-for-service life assessment, brittle fracture assessments, corrosion assessments, and blast, fire, and heat damage assessments.


2021 ◽  
Vol 23 (08) ◽  
pp. 549-566
Author(s):  
Vinod Kumar ◽  
◽  
S.S Dhami ◽  
Deepam Goyal ◽  
◽  
...  

Condition-based maintenance is always an important strategy of maintenance to prolong the effective life of rotating machines as they run on high speeds with a variety of loads in some cases under severe conditions. If the monitoring of the current condition is not done accurately then rotating machines such as turbines, engine, bearing, shafts, gearbox, motors, and compressors leads to catastrophic failures with some serious consequences on the rate of production, safety, loss of manpower and sudden increase in repairing cost. Condition-based maintenance is also be called predictive type maintenance is a far superior technique as compared to preventive maintenance and run-to-break maintenance. In predictive maintenance current status of the machine while in operation, being monitored carefully and based on a brief analysis of the future condition of the machine predicted. This paper going to review the various intelligent condition monitoring techniques developed or used by various researchers to monitor the health of rotating machines and able to predict the faults at the earliest time.


2021 ◽  
Author(s):  
SeHyuk Park ◽  
Hamad Alnuaimi ◽  
Umar Amjad ◽  
Tribikram Kundu

Abstract Detecting internal defects such as fatigue cracks in their early stages is critically important to avoid catastrophic failures. However, detection of micro-scale defects poses a challenge to NDT/SHM (Non-Destructive Testing & Structural Health Monitoring) community. Conventional linear ultrasonic techniques that use absolute time of flight and attenuation to monitor damage progression encounter difficulty in detecting small defects. On the other hand, nonlinear ultrasonic techniques have been proven to be more reliable and sensitive to micro-scale defects. This study uses the nonlinear Sideband Peak Count Index (SPC-I) technique to evaluate the nonlinearity of the material. The problem is simulated using the finite element method (FEM). Fatigue cracks are simulated as breathing cracks. The problem is modeled as an infinite medium to minimize the geometrical effects such as reflections from the boundaries. A narrow band signal is excited and propagated through the material in a single sided excitation/detection setup. The degree of nonlinearity caused by breathing cracks is investigated for multiple configurations. First, the problem is modeled with no cracks to be taken as a reference condition. Then thick crack and thin crack (breathing crack) are modeled, analyzed, and compared. Finally, problems with different number of breathing cracks are simulated and analyzed. All simulated results are compared to investigate the dependence of the degree of nonlinearity on the density and orientation of the cracks.


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