News the major Japanese vehicle assemblers in the US. In addition to 10 manufacturing and assembly facilities in the US, Plumley maintains distribution and R&D operations at its headquarters in Tennessee, USA, and a sales office in Michigan. It employs about 1600 people. Contact: Dana Corporation, PO Box 1000, Toledo, Ohio 43697, USA. Tel: +l 419 535 4500; Fax: +l 419 535 4643.
Latest edition of reference guide published Parker Seals has produced the latest edition of its informative Sealing Handbook. The 152 page technical reference book contains in-depth information on the fundamental principles of the sealing process, on pressure media, seal selection, and installation
techniques. The profiles and operating principles of seals in the Parker range are discussed extensively, and the behaviour of sealing materials in lubricants and working fluids such as mineral oil emulsions, phosphoric esters. chlorinated hydrocarbons and compressed air is characterised. The guide also contains a 14 page section on applicalion problems and causes of seal failure. Contact: Parker Seals, Star House, 69-71 Clarendon Road Watford, Herb WDl lLP, UK. Tel: +44 1923 239009; Fax: +44 1923 238833.
Facing the fluid sealing challenges of the 90s The Fluid Sealing Association held its technical symposium on Optimizing the Performance of Gasketed Connections last month in Houston, Texas. Following is a list of papers presented, which may be of interest.. Bolted flange joint assembly, improving the human factor (E Hayman. Providence Bolting Technologies). Creep and leakage properties of modified PTFE (Dr J Latte, ISTAG AG, A Klinger Group). Avoiding leaks or blow--out of non-metallic gaskets: gasket tensile strength vs. Compressive stress (D Burgess. Garlock). The effect of flange alignment on the sealing ability of gasket materials (S Boss, Hollingworth & Vase).
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Development of test procedure for fire resistance qualification of gaskets (D Mills. W.L. Gore). A link between gasket tightness and fugitive emission leak definition (Dr L Marchand. Ecole Polytechnique). Leak prevention - the balanced approach (Dr J Kuo, Inertech). Live loading of bolted flange connection to improve gasket performance (R Corbett, Rotabolt]. A performance based specification for spiral wound gaskets (G Davet, Solon Manufacturing). Inward buckling of spiral wound flexible graphite filled gaskets for piping flanges (R Mueller, Exxon). Inward buckling of spiral wound gaskets (L Stanford, Garlock). Determination of design gaskets assembly stress with the new constants - exact method (A Guizzo, Asberit). Alternative ASME rules for bolted flange joints with ring type gaskets (R Mikita, 3M). Recent and evolving gasket testing specifications in Europe and their effects on gasketing (J Hoyes, Flexitallic Sealing Materials). Copies of the symposium papers may be obtained from the FSA. Contact: Fluid Sealing Association, 994 Old Eagle School Road, Suite 1019, Wayne, PA 19087-1802, USA. Tel: +1610 971 4850; Fax: +l 610 9714859.
Salant wins Worthington medal Richard F. Salant) Sc.D., P.E.. professor, Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, has received the Henry R. Worthington Medal of ASME International. The Worthington Medal was eslablished in 1980 and is presented for eminent achievement in the field of pumping machinery. Dr. Salant received the medal for “the development of seals, all crucial to the operation of pumping machinery.” Dr. Salant has been an engineer and educator in mechanical engineering throughout his professional career. He developed the first computerized analysis of mechanical seal and the first elastohydrodynamic analysis of lip seals to explain the reverse pumping, load support and sealing mechanisms. Dr. Salant also demonstrated the importance of thermal deformation on the stability of two-phase mechanical seals, and developed a numerical analysis to predict the behaviour of upstream pumping spiral groove mechanical seals. He explained the physical mechanism by which hydropads provide load support in mechanical seals, and he improved the computational methods for addressing cavitation in them. Dr. Salant also showed that optimally designed mechanical seals .with compliant faces (foil seals) are more stable than conventional seals. He also was responsible for developing a non-leaking submersible motor seal, a secondary gas/liquid mechanical seal and a submersible pump gas-liquid separator. A Fellow of ASME, Dr. Salant is currently associate editor of the ASME Journal of Tribo1og.y and has been
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Static sealing associate editor of the ASME Journal of Fluids Engineering. Contact: ASME International, 345 East 47th St., New York, NY 10017-2392, USA. Tel: +l 212 705 7740.
Lubricants could ease engine seals operation Argonne National Laboratory has joined with the Allison Engine Company to explore the use of low-cost, oxide-based lubricant coatings to enable turbine-engine regenerator seals and cores to operate safely at temperatures up to 1100°C. Meeting this requirement is the key to the development of high-performance gas turbine engines for turbine-engine and hybrid-electric vehicles. Successful development and implementation of such coatings could substantially reduce fuel use, since a properly designed regenerator seal and core assembly can increase the fuel efficiency of a turbine engine by as much as 30%. The coatings may also contribute to a cleaner environment by reducing emissions. Argonne is testing coatings to enable turbine-engine regenerator seals and cores to operate at temperatures to 11oo”c. Industry is interested in these coatings for hot-forming operations. The coatings are of interest because of their low friction and wear properties. They would be applied to dies and other components used in metal (and glass/ceramic) forming operation. The researchers are also exploring new alloys and coating compositions that can promote the formation of wear-resistant and lubricious oxides that could eliminate the use of time-consuming and expensive plasma-spray coatings. Contact: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439-4803, USA. Tel: +1630 252 2000.
Form-in-place gaskets used in digital phones Electronic shielding expert, IVC’s pioneering form-in-place gasket material XYShield is being used on one of the latest digital phone handsets, the Orbitel 905. XYShield comprises a single part, electrically conductive, non-slump silicone elastomer that is applied directly to the Orbitel handset using extremely
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accurate computer controlled dispensing equipment. Gaskets with intricate shapes and fine cross sectional profiles down to 0.4 mm diameter are applied in X, Y, and 2 axes to the metallised surface of the handset. The sealant combines low electrical resistance with mechanical properties such as good adhesion, tear strength and temperature tolerance to deliver an EMI seal with good performance and durability. To ensure a high level of consistency and reliability during application of the gasket, the process is monitored using a three axis, video edge detection measuring instrument that incorporates full statistical process control capabilities. This ensures long term repeatability within preset tolerance bands. Typical material characteristics of the form-in-place gaskets include silicone elastomer with silver conductive filler, a temperature range from -40 to lOO”C, an adhesion strength of 8.7 N/cm and a tear strength of 3.71 kN/m. Contact: IVC, Unit 14, Bromford Industrial Estate, Credenda Road, West Bromwich B70 7JE. UK. Tel: +44 1221511 1115; Fax: +44 121 544 5253.
Testing gaskets for fire resistance The integrity of gaskets for flanged joints exposed to fires is of key importance to users who require a seal that will not blow-out or deteriorate under adverse conditions. This is particularly important for highly toxic or combustible fluids. Since asbestos has fallen into disfavour, many replacement materials have appeared, some with questionable fire resistance characteristics. The evaluation of fire resistance is a key factor in the qualification of new products, establishing whether a given material will survive long enough for safe system shutdown to be achieved. The Tightness Testing and Research Laboratory of Ecole Polytechnique de Montreal, and JPAC Inc, have developed two fire simulation test procedures for gaskets, with the support of the Materials Technology Institute of the Chemical Process Industries and the Pressure Vessel Research Council. These methods were presented at the FSA gasket symposium in October. The first test of the two proposed, the fire simulation screen test (FIRS), is performed with a modified version of an existing aged tensile relaxation screen test fixture (ATRS), adapted to perform short duration thermal exposures at 1200°F. In the ATRS fixture, mechanical properties of a gasket are measured over a period of days to weeks under compressive stress, recreating gasket aging effects in bolted joints. The FIRS test is a short term test, using a similar fixture with the springs removed, for more rapid and repeated heat up. Two weak direction gasket samples are loaded into the rig at 5000 psi, heated to 1200°F within 30 minutes and stabilised for 15 minutes. Open flame tests are not used because of the difficulty of measuring and controlling the flame. At room
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