An Approach for Analysing Boiler Tubes Ultrasonic Inspection Data to Support Decision Making

Author(s):  
Soudabeh A. Noori ◽  
John W. H. Price

There is now much interest in the development of risk based strategies for maintenance planning including assessing appropriate inspection strategies and making economic life estimates of critical components. This study examines this problem from a practical point of view by studying a significant body of tube thickness inspection data collected in a power station. This data naturally has all sorts of difficulties. For example there are issues related to the accuracy and correctness of the measurements. Then there is the issue of how to use the data to determine deterioration rates and life expectancy. This paper examines this data using: • a method developed by the authors: a procedure based on a “warning level” approach, and • a suggested interpretation of the American Petroleum Institute’s technique of “risk based inspection”.

Author(s):  
Jun Takahashi ◽  
Shinsuke Sakai

Periodical inspection is necessary for stable operation of the plant. But usually, inspection cost and inspection period are limited, and it is difficult to inspect all of the objective location of the plant in allowed cost and period. Therefore, for maintenance planning, probability of failure is presumes by the obtained sample size inspection data. In that case, presumed probability of failure includes uncertainty, and the one-side tolerance limit of the probability is changed by the sample size of the inspection. For maintenance on boiler tubes of fossil fuel fired power plants, only limited sample size inspection data can be used for maintenance planning. On the other hand, the conditions of the tubes for maintenance are different because environmental conditions of the tubes like actual temperature are different. Then the inspection results don’t demand enough information to presume probability of failure because the standard deviation is not known. But usually to presume probability of failure for maintenance, the standard deviation is not considered only the average is used. Therefore, considering mainly uncertainties depend on sample size of the inspection data, presumed probability of failure is related to rational maintenance planning.


1990 ◽  
Vol 22 (1-2) ◽  
pp. 347-352 ◽  
Author(s):  
C. Paffoni ◽  
B. Védry ◽  
M. Gousailles

The Paris Metropolitan area, which contains over eight million inhabitants, has a daily output of about 3 M cu.meters of wastewater, the purification of which is achieved by SIAAP (Paris Metropolitan Area Sewage Service) in both Achères and Valenton plants. The carbon pollution is eliminated from over 2 M cu.m/day at Achères. In order to improve the quality of output water, its tertiary nitrification in fixed-bed reactors has been contemplated. The BIOFOR (Degremont) and BIOCARBONE (OTV) processes could be tested in semi-industrial pilot reactors at the CRITER research center of SIAAP. At a reference temperature of 13°C, the removed load is approximately 0.5 kg N NH4/m3.day. From a practical point of view, it may be asserted that in such operating conditions as should be at the Achères plant, one cubic meter of filter can handle the tertiary nitification of one cubic meter of purified water per hour at an effluent temperature of 13°C.


IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Lucas Vago Santana ◽  
Alexandre Santos Brandao ◽  
Mario Sarcinelli-Filho

2009 ◽  
Vol 624 ◽  
pp. 1-18 ◽  
Author(s):  
Jean Marc Chaix

Microstructure is the key scale to understand and describe sintering mechanisms and their consequences at the macroscopic level. As modeling techniques are continuously developing, the need for input data and comparison with more and more accurate descriptions of the evolution is expected to create a growing demand for quantitative microstructure data. Image analysis is the classic way to get these data. This paper reviews the practical use and progresses of this old technique in the sintering literature during the past and recent years. The place of basic tools and more recent ones, such as 3D imaging, are discussed from a practical point of view accounting from sintering models needs: mean size and size distributions in pores and grains, homogeneity, sintering trajectories…


2005 ◽  
Vol 13 (3) ◽  
pp. 533-563 ◽  
Author(s):  
Fred Phillips

This paper explores the evolution of the techno-management imagination (TMI). This is the process by which, in times of crisis, managers think not just out of the box, but out of the very reality in which the box resides. Tacit social consensus, also known as corporate culture, can lead to a shared, implicit, and incorrect view that certain actions are impossible. TMI transcends local culture, accessing technological solutions that are unknown and/or unimagined. Members of the organization tend to call such solutions “magic”. The paper looks at social, perceptual, and managerial aspects of magic from a practical point of view that is grounded in research. It examines the risks of TMI, and concludes with suggested perspectives and research questions for management scientists and cognitive scientists.


Exchange ◽  
2005 ◽  
Vol 34 (2) ◽  
pp. 149-166 ◽  
Author(s):  
Henri Gooren

AbstractThe central question of this article — why people may change their religious affiliation or become disaffiliated — is relevant from both an academic and a practical point of view. The article makes first an inventory of existing literature on religious conversion. Next I sketch the contours of the new conversion careers approach I am currently working on. I make some comparisons with a region that is not usually mentioned in the literature on conversion: Latin America. These comparisons are based on my earlier fieldwork on Roman Catholicism, Pentecostalism, and Mormonism in Costa Rica and Guatemala (H. Gooren, Rich among the Poor: Church, Firm, and Household among Small-scale Entrepreneurs in Guatemala City, Amsterdam: Thela Thesis 1999).


Habarshy ◽  
2021 ◽  
pp. 50-60
Author(s):  
A.B. Myrzhiyeva ◽  
M.Zh Suleimenov ◽  
Uslu Ugur ◽  
A.S. Ibazhanova ◽  
L.O Zhanteliyeva L.O

The scientific article presents the duration of acaricidal effect of «Kenem» drug, and its economic feasibility for protecting cattle against ixodic ticks. As a result of the study, the acaricidal efficacy and the duration of the residual acaricidal effect of drugs are important components in the planning of anti-tick measures. From a practical point of view, the economic feasibility of treating cattle against ixodic ticks in the presented conditions of acaricides in the southern regions is considered important. Despite the fact that the cost of the drug per 100 head exceeds the cost of a similar drug by 1 788.15 tenge, the frequency of its use is less, and additional installations are not required. This is due to the long duration of residual acaricidal effect of Kenem, which is 30 days, which allows to reduce the number of therapeutic measures.When calculating the economic feasibility for the use of acaricides to protect cattle against ixodic ticks, the most convenient way to prevent the sucking of ixodic ticks to animals is the local application of Kenem, which does not require special equipment and special skills of technical staff. Drug duration is 30 days, therefore the cost of its use for the entire season of active ticks per 1 animal is 44% cheaper, compared to veteran, i.e. 1,421.4 tenge.


2018 ◽  
Vol 18 (1) ◽  
pp. 110-132
Author(s):  
Lukas Barth ◽  
Andreas Gemsa ◽  
Benjamin Niedermann ◽  
Martin Nöllenburg

External labeling deals with annotating features in images with labels that are placed outside of the image and are connected by curves (so-called leaders) to the corresponding features. While external labeling has been extensively investigated from a perspective of automatization, the research on its readability has been neglected. In this article, we present the first formal user study on the readability of leader types in boundary labeling, a special variant of external labeling that considers rectangular image contours. We consider the four most studied leader types (straight, L-shaped, diagonal, and S-shaped) with respect to their performance, that is, whether and how fast a viewer can assign a feature to its label and vice versa. We give a detailed analysis of the results regarding the readability of the four models and discuss their aesthetic qualities based on the users’ preference judgments and interviews. As a consequence of our experiment, we can generally recommend L-shaped leaders as the best compromise between measured task performance and subjective preference ratings, while straight and diagonal leaders received mixed ratings in the two measures. S-shaped leaders are generally not recommended from a practical point of view.


Author(s):  
R. M. Chandima Ratnayake ◽  
Tore Markeset

Oil and Gas (O&G) platforms in the North Sea are facing aging problems as many of the installations have matured and are approaching their design lifetime. Flowlines are used to transport oil and gas well stream from the wellhead to the production manifold. They are categorised as one of the most critical components on a production facility. Flowline degradation takes place due to corrosion and erosion. The deterioration of a flowline may increase the risk of leakages, ruptures, etc., which shall lead to serious HSE (health, safety and environmental) and financial consequences. Any such risks have a direct impact on the O&G installation’s technical integrity as well as the operator’s sustainability concerns. Conventionally, pipelines are designed with safety provisions to provide a theoretical minimum failure rate over the life span. Furthermore, to reduce the risk of failure various techniques are routinely used to monitor the status of pipelines during the operation phase. The existing methods of flowline health monitoring planning requires one to take into consideration the operator’s plant strategy, flowline degradation mechanisms, historical data, etc. A technical condition report is made based on findings’ reports and degradation trends. This report recommends the inspection of a number of points on the flowlines in a certain year using non-destructive evaluation methods such as visual inspection, ultrasonic testing, radiographic testing, etc. Based on the technical condition report, in general for a certain preventive maintenance shutdown, 10 to 15 flowline inspection openings are accommodated as finance, time and resource availability are taken into consideration. However, it is customary to plan to open more locations in a certain inspection package than can be inspected and minimization of such points is at present done on an ad hoc basis. This paper suggests a formal model and a framework to formally minimize the number of visual inspections by executing the plant strategy as well as HSE concerns. The model is derived using analytic hierarchy process (AHP) framework, which is a multi-criteria decision-making approach. The model is developed based on literature, industrial practice, experience as well as real inspection data from a mature offshore O&G installation located on the Norwegian Continental Shelf.


The investigation of development described in a previous communication was extended by the application of microscopic methods. The fact that both the silver haloid and the resulting silver are distributed through the film in the form of particles of minute but measurable size, allows us in this way to detect finer qualitative differences in, and to draw independent deductions on the processes of exposure and development. The size of the grain is important, both from the practical point of view and from the theoretical: in the one case as bearing on spectroscopical and astronomical photography, in the other on account of the great importance of the degree of surface-extension for heterogeneous systems. The method has been used previously by Abney, Abegg, Kaiserling, Ebert, and others, but by far the most systematic and important inquiry is that of K. Schaum and V. Bellach.


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