ULTRASONIC MONITORING OF FLAW GROWTH AT 600 ̊C (1110 ̊F) IN AN OPERATIONAL POWER PLANT
Flaw growth monitoring at operational temperatures in high-temperature plants has long been recognised as a highly desirable inspection goal, particularly in regard to effective outage management and lifetime extension of existing plants, and increasing the reliability of future plants through the incorporation of active monitoring systems. However, despite considerable efforts in the area of high temperature inspection, practicable solutions for implementing long-term continuous flaw growth monitoring in operational power plants have proved elusive. KANDE International and E.ON have worked together over a number of years to develop a viable means of performing long-term monitoring of known flaws in operational fossil-fuel power plant components, where operating temperatures can be as high as 600°C (1110°F), and we have previously reported on the development and laboratory testing of permanently installed high temperature ultrasonic probes and associated testing techniques. In this paper we report on the progress made to date in a new study that is investigating the wider problems associated with performing remote monitoring of real flaws in a main steam line in an operational plant. We discuss the approaches used to address a range of issues including: the permanent attachment of probes close to known flaws; designing an instrumentation system capable of recording data and transmitting it to an off-site location with minimal operator intervention; and the development of software tools to display and analyse the resulting data so that flaw growth can be identified and measured. We comment on the lessons learned to date and on how the experience gained will influence the future development of the technology.
Ultrasmart: Developments in Ultrasonic Flaw Detection and Monitoring for High Temperature Plant Applications
Plant in the power generation, petrochemical and metals processing industries is subject to increasingly onerous operational and regulatory requirements. Where plant that operates at high temperature is involved, the costs associated with shutdown for planned or unplanned inspection to meet these requirements can be particularly high. The ability to perform condition monitoring or flaw detection at on-line plant temperatures would enable plant to remain in operation for longer periods, reduce the risk of damage from thermal cycling associated with periodic shutdowns and allow shutdowns to be completed more quickly. The associated minimizing of the loss of revenue caused by frequent and lengthy shutdowns is a highly attractive proposition to the plant operators. This paper reports on progress in the Ultrasmart Project, which is being undertaken by a consortium of UK companies and aims to address the problems associated with performing ultrasonic inspection on pressure vessels and piping at temperatures exceeding ∼350°C. A brief review of the state of current industry capabilities is given and then details of the developments investigated within Ultrasmart are reported and discussed. These include: • Liquid cooled transducers and automated scanning mechanisms suitable for deployment on components with surface temperatures up to ∼500°C. • Permanently mounted piezoelectric transducers suitable for long term flaw growth or component thickness monitoring at temperatures up to ∼750°C. • Techniques, procedures and protocols necessary to achieve reliable and quantifiable inspection capability at high temperatures. • Use of a novel non-resonant thin film Aluminum Nitride (AlN) transducer for in-situ component monitoring.© 2007 ASME
Gender Differences in Predicting Productivity of Faculty
Since the 1960s, the overall proportion of female faculty in higher education has increased significantly, from 20 percent in 1969 to 27 percent in 1984, although this improvement is not reflected in all disciplines (Ransom, 1990). In journalism, the percentage of women faculty rose from 10 percent in 1969 to 30 percent in 1984.' Despite these gains, the recent literature demonstrates that female faculty must still face a number of inequity issues (Hensel, 1990; Maitland, 1990; Moore & Sagaria, 1991). In the journalism and mass communication field, several studies have pointed out that female faculty members are less likely to be tenured (Fedler, Counts, & Smith, 1984; Grunig, 1987) and earn less than their male counterparts, controlling for such intervening variables as rank, years of teaching experience, and educational level (Stuart & Dickey, 1986; Weaver & Wilhoit, 1988; see also Fedler et al., 1984; Kelly, 1989; Stuart & Dickey, 1991). One should add, though, that this salary differential tends to be small after controls. Provided that some job inequalities persist between male and female faculty in schools and departments of journalism and mass communications, the next question we need to address is why? Research on academic women in U.S. universities has suggested that such a differential treatment occurs because female faculty tend to publish less than their male colleagues ( e g , Centra, 1974; Chamberlain, 1988; Fulton, 1975; Seeborg, 1990; Simeone, 1987). Some discipline-specific studies have also reported that male faculty members are significantly more productive than their female counterparts in education (e.g., Lipman-Blumen, Stivers, Tickamyer, & Brainard, 1975) and psychology (e.g., Bronstein, Black, Pfennig, & White, 1986; Guyer & Fidell, 1973). But again these differences are often small or tend to disappear when such controls as rank and academic experience are introduced. In journalism and mass communications, however, there is some evidence that female faculty are closing the publication gap. A growing number of content analyses have revealed a continuous increase in female authorship since the 1960s (Cooper, Stewart, & Friedley, 1985, 1990; Dupagne, Potter, Cooper, & Dashiell, 1991; Sharp, Turk, Einsiedel, Schamber, & Hollenback, 1985) . More recently, Dupagne, Potter, and Cooper (in press) have investigated authorship patterns by gender in eight leading communication journals from 1965 to 1989. They found