May 2006FEATURES Reconditioning Power-Generation Components with Thermal Spray The growth of power-generation facilities throughout the world has been unprecedented. With this expansion, plant superintendents and maintenance supervisors will tell you that a tremendous amount of effort is expended behind the scenes to keep these power generating facilities running smoothly. These facilities face numerous corrosion and/or wear issues, and maintenance must regularly be performed on various machines and systems. In an effort to reduce downtime, plant superintendents and maintenance supervisors have turned to and have come to depend upon thermal spray technology to extend the life of power-generating components and systems. Coatings manufactured by this technology are being used throughout the power-generating industry in applications such as water pumps, conveyor screws, boiler tubes, and coal crushers. K. Dobler Masking for Thermal Spray Coatings When specific areas of a part must be thermally sprayed, the areas that are not to be coated must be masked. The masking method and materials used need to be selected based on the spray equipment and automation employed to apply the coating. The choice of maskant for each job is essential to the ultimate integrity of the coating and the total cost to process the part(s). E.R. Sampson Assessing Toughness Levels for Steels to Determine the Need for PWHT Postweld heat treatment (PWHT) is applied to welded steel assemblies primarily to reduce the likelihood of brittle fracture. This is achieved through a reduction in the level of tensile residual stresses and through tempering of hard, potentially brittle, microstructural regions. There are, of course, economic and logistical incentives to avoid PWHT wherever possible. D. J. Abson et al. Grit Blasting: Starting Your Thermal Spray Job Correctly Grit blasting, or the roughening of the substrate to be thermal sprayed, is as important as the spraying itself. It cleans the surface and roughens the substrate to form an anchor tooth pattern to improve the coating adhesion. The measurement and control of the surface roughness pattern need to be better monitored and controlled for thermal spray coatings. This article is based on my experience working for a manufacturer of grit blast equipment. It looks at what is common practice, current writings, and recommended procedures to improve this practice. E. R. Sampson WELDING RESEARCH SUPPLEMENT Prediction of Ferrite Number of Duplex Stainless Steel Clad Metals Using RSM (.pdf) Response surface methodology (RSM) was used to establish a relationship between process parameters and Ferrite Number for duplex stainless steel clad metals. T. Kannan and n. Murugan et al.
Welding Aluminum
Sheet Using a High-Power Diode Laser (.pdf) Predictions of
Microstructures when Welding Automotive Advanced High-Strength Steels
(.pdf) |
Departments
Classifieds and Advertiser Index
Welding Journal (ISSN 0043-2296) is published monthly by the American Welding Society for $90.00 per year in the United States and possessions, $130 per year in foreign countries: $6.00 per single issue for AWS members and $8.00 per single issue for nonmembers. American Welding Society is located at 550 NW LeJeune Rd., Miami, FL 33126-5671; telephone (305) 443-9353. Periodicals postage paid in Miami, Fla., and additional mailing offices. POSTMASTER: Send address changes to Welding Journal, 550 NW LeJeune Rd., Miami, FL 33126-5671. Readers of Welding
Journal may make
copies of articles for personal, archival, educational or research
purposes, and which are not for sale or resale. Permission is granted
to quote from articles, provided customary acknowledgment of authors
and sources is made. Copyright © 2006 by
American Welding Society in both printed and electronic formats. The
Society is not responsible for any statment made or opinion expressed
herein. Data and information developed by the authors of specific
articles are for informational purposes only and are not intended for
use without independent, substantiating investigation on the part of
potential users. For permission to use Copyright information please contact Copyright.com |


