Teledyne

Total hafnium available worldwide from nuclear zirconium production is estimated to be 130 metric tons annually. The annual usage, in all forms, is about 85 t. The balance is held in inventory in stable intermediate form such as oxide by the producers Teledyne Wah. Chang (Albany, Oregon) and Western Zirconium in the United States Ce2us in France Prinieprovsky Chemical Plant in Ukraine and Chepetsky Mechanical Plant in Russia (crystal bar). 

Hafnium, brochure. Teledyne Wah Chang Corp., Albany, Oreg., 1987, p. 11. 

Laurence A. Jackman Carlos N. Ruiz Teledyne Allvac... 

B. Langfoid, I. H. Stice, L. Latimei, and R. E. Walsh, Ttetermination of Hydrogen by Impulse Furnace Fusion Employing Chromatographic Detection, Teledyne Wab Chang Corp., Albany, Oieg., 1974. 

J. Eialey, Elemental Mnalysis byMrgon Plasma Emission Spectroscopy, Teledyne Wab Chang Corp., Albany, Oieg., 1988. 

Fig. 5. Vacuum-distilled titanium sponge produced by magnesium reduction at Teledyne Wah Chang (Albany, Oregon).

Residual traces of zinc are released during vacuum sintering of cemented carbides made with recovered powders. This can be troublesome when a buildup of zinc occurs in the furnace. Teledyne Advanced Materials further developed this process on a commercial basis by achieving zinc levels in the low ppm range (<30 ppm). The fact that the materials were vacuum-sintered in their original form where certain impurities are removed leads to lower impurity levels in the recovered powders. There is a slight oxidation or loss of carbon that must be compensated, otherwise the recycled powder is not in any way inferior to the original. 

In the initial thiocyanate-complex Hquid—Hquid extraction process (42,43), the thiocyanate complexes of hafnium and zirconium were extracted with ether from a dilute sulfuric acid solution of zirconium and hafnium to obtain hafnium. This process was modified in 1949—1950 by an Oak Ridge team and is stiH used in the United States. A solution of thiocyanic acid in methyl isobutyl ketone (MIBK) is used to extract hafnium preferentially from a concentrated zirconium—hafnium oxide chloride solution which also contains thiocyanic acid. The separated metals are recovered by precipitation as basic zirconium sulfate and hydrous hafnium oxide, respectively, and calcined to the oxide (44,45). This process is used by Teledyne Wah Chang Albany Corporation and Western Zirconium Division of Westinghouse, and was used by Carbomndum Metals Company, Reactive Metals Inc., AMAX Specialty Metals, Toyo Zirconium in Japan, and Pechiney Ugine Kuhlmann in France. 

A number of cemented carbide producers market some or all primary materials, ranging from monocarbides to binary or ternary soHd solutions involving TiC, TaC, NbC, or WC. Among the suppHers offering these materials are Keimametal Inc., GTE Products Corp., Teledyne Wah Chang, and Tokyo Tungsten Co. Ltd. Keimametal Inc, also manufactures TiN and TiCN powders. 

Figure 7-3. Conventional or unbalanced nozzle safety relief valve. By permission. Teledyne Farris Engineering Co.

Extracted by permission from Teledyne-Farris Engineering Catalog. 

Figure 7-22. Liquids overpressure sizing factor, Kp, for other than 25% overpressure. Applies to Non-code iiquids oniy using conventional and balanced valves. By permission. Teledyne Farris Engineering Co.

Figure 7-24. Viscous iiquid vaive sizing using the method of APi RP-520. Reprinted by permission, Teledyne Farris Engineering Co. and Sizing, Selection and Installation of Pressure-Relieving Devices in Refineries, Part I Sizing and Selection, API RP-520, 5th Ed., July 1990, American Petroleum Institute.

Figure 7-28. Variable or constant backpressure sizing factor, K, for liquids only, BalanSeal valves. Use this factor as a divisor to results of constant backpressure equations or tables. By permission. Teledyne Farris Engineering Co.

DISC TYPE DISC SIZE DISC MATERIAL SET PRESSURE PSIG TELEDYNE FERRIS 2600 4500 DRESSER 1900 1900-30 1900-35 CROSBY JOS/JBS CROSBY JB CROSBY JO KUNKLE 5000 THRU 5999 LONERGAN D DB... 

Teledyne Farris Engineering Catalog 187 C., Teledyne Farris Engineering Co., Palisades Park, N.J. 

ASME Sect. VIII, Div. 2, 1986 Edition Teledyne Wah Chang Albany... 

Registered Trademark of Allegheny Ludlum Industries t Registered Trademark of Armco Steel Corporation t Registered Trademark of Vasco-Teledyne Company Registered Trademark of Republic Steel Corporation... 

---