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March/April 2013 M P R 37 0026-0657/13 ©2013 Elsevier Ltd. All rights reserved product showcase product showcase PM bearings support one of the world’s longest suspension bridges Ssangyong develops whisker-reinforced ceramic Ssangyong Materials Corp has launched SW400 and SW800 silicon carbide (SiC) whisker- reinforced ceramic grades. Aluminium oxide has been used successfully as a cut- ting tool material for many years in high-speed machin- ing, mainly due to its excel- lent hardness and chemical stability at high tempera- tures. However, the applica- tion of aluminium oxide can be limited in interrupted cutting of high nickel-based alloys at high cutting speed because of its low resistance to fracture. The SW400 and SW800 ultra-strong whiskers improve fracture toughness and notch wear resistance in the machining of super- alloys at high speed cutting. SW400 and SW800 also have high productivity and extended reliability in the machining of nickel and cobalt-based alloys, as well as Inconel, Stellite, HSS and so on. They have excellent wear and thermal shock resistance at high surface speed. Ssangyong Materials Corp also offers coated whisker ceramic inserts for increased performance. C I Hayes installs quench furnace Federal-Mogul Corporation has developed a range of maintenance-free bearings for the Hardanger Fjord sus- pension bridge in southwest Norway, which spans 1,310 m (4,297 ft) between pylons. Federal-Mogul’s bearings are made of a thin-walled, self-lubricating sliding mate- rial called deva.bm that pro- vides a larger load-carrying surface, providing sufficient durability for the life of the bridge without repair or replacement. If the sliding layer became damaged by exposure to loads in excess of the design values, the structure of the joint is pro- tected and the plain bearing can function at a reduced level, according to Federal Mogul. Conventional roller bear- ings are not suitable for the prolonged, minute move- ments of the bridge while under constant heavy load and could potentially suffer from surface failures called ‘brinelling.’ The complete bridge includes 120 spherical plain bearings with a shaft diame- ter of 160 mm and eight with a shaft diameter of 300 mm, used for the main retain- ing cables adjacent to the two bridge towers. The joint balls are made from stain- less steel, which is pressed into a plain bearing made from deva.bm. A low-friction sliding bearing consists of a backing comprising steel, stainless steel or bronze, with a deva.metal surface layer. This surface layer is a bronze material manufac- tured using powder metallur- gy – it is highly compressed and coated with a layer of solid lubricant material, such as graphite or PTFE. The bearing housing forms a two-part spherical ring, also lined with deva.bm, and the design is completed using thrust washers that are also made from deva.metal, which absorb axial forces. The bear- ings are suitable for dry run- ning at slow sliding speeds with very high resistance and are well-suited for extreme temperatures and corrosion. In all, Federal Mogul will supply 128 spherical plain bearings made using its DEVA self-lubricating mate- rial technology. They will be used to accommodate the small movements that occur between the bridge and its supporting cables. “Wind pressure, load and vibrations from traffic flow and temperature changes are all contributors to road move- ment on suspension bridg- es,” said August Stadlmayr, managing director of Federal- Mogul DEVA GmbH. “The Hardanger Fjord bridge was particularly challenging because of its length and the loads generated.” A number of bridges around the world also use the Federal-Mogul technology, including: the flap bridge in the port of Valencia, Spain; the bridge over the Peene near Anklam, Germany; and the Rethe Bridge in Hamburg, Germany. The Hardanger Fjord suspension bridge in southwest Norway. C.I. Hayes, a Gasbarre Furnace Group Company, installed a batch atmosphere, 20 bar pressure quench (BAPQ) furnace in Q4 2012. The Gasbarre furnace is designed for a proprietary heat treating process and is equipped with a 3 zone heat chamber with a maximum operating temper- ature of 1250°C. Capabilities include net loading of 3000 lb, 20 bar nitrogen quench, and 15 second load transfers between chambers. C.I Hayes’ quench furnace.
