TPI July 2011

developments products &

Super-size, superalloy tube extrusions for USC power production

produced at Special Metals Wiggin Ltd, in Hereford, England.

Huntington, West Virginia, where both alloys were developed. While alloy 617 is a well-established solid solution alloy, offering high strength and heat resistance for extreme conditions at highly elevated temperatures, alloy 740 is a precipitation-hardenable alloy, specifically designed for the rigours of USC service. Thesesuper-size, superalloy tubeswill be tested by many organisations worldwide for application in various A-USC programmes. Prior to production of the tubes in Houston, a large Nimonic alloy 263 tube was extruded at the Wyman Gordon mill in Livingston, Scotland. Alloy 263 is another superalloy that may find application in A-USC designs. The ingot for manufacture of that tube was

Members of PCC Energy Group are producing some of the largest superalloy tubular products ever manufactured. Wyman Gordon Forgings, Houston, Texas, has extruded the huge tubes specifically for headers for the next generation of advanced ultra super critical (A-USC) coal-fired power boilers. Inconel 617 and 740 tubes, with 15" diameter, 3.5" wall and 34ft length, are produced on a 35,000-ton vertical press. It is considered a major technology advancement for USC development programmes in North America, Europe and Asia. The ingots for extrusion were vacuum- induction melted and re-melted at Special Metals Corporation mill at

The development of A-USC power technology is seen as a means of reducing the world’s consumption of coal, as the units are projected to operate at steam temperatures of 700 to 760ºC, resulting in power production efficiencies of 48% or higher. This efficient operation has the added effect of reducing pollution problems associated with emission of fossil fuel combustion products, such as carbon dioxide, sulphur dioxide and oxides of nitrogen.

Pcc energy Group – USA www.pccenergygroup.com

ASTM A 790 duplex pipes Butting, Germany, has expanded its components store in Knesebeck to include ASTM A790 duplex stainless steel pipes, in order to offer customers quicker coverage of their needs at short notice.

supplies pipes with acid-cleaned and passivated surfaces, above and beyond the requirements of ASTM A790. H butting GmbH & co KG – Germany info@butting.de www.butting.de

in its manufacturing technology. In accordance with the standard, all destructive tests (including hardness, tension, flattening and bending tests) and non-destructive tests (eg water pressure and eddy current test) are carried out on the pipes. The producer

The pipes, in material 1.4462/UNS S31803/UNS S32205 and based on ASTM A790, are in store in sizes from OD 219.10 to 406.40mm, with wall thicknesses from 3.76 to 9.53mm. In addition, the components store continues to stock ASTM A928 duplex pipes in sizes OD 33.7 to 323.9mm. For larger projects and individual needs, Butting can also produce ASTM A790 pipes in other project-specific sizes. The use of duplex steel is suitable due to its high level of corrosion resistance, in particular stress corrosion cracking, greater robustness and higher stretch limits. ASTM A790 covers in general the basics and the requirements for manufacturing seamless and welded steel pipes. With regard to duplex materials, it requires a welding procedure without filler metal, which Butting implements

Butting has expanded its Knesebeck components store

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July 2011 Tube ProducTs InTernaTIonal