Vacuum
news
the Physics Exhibition in April 1967. The equipment includes an electron bombardment source, lilm thickness monitor, a high conductance high vacuum valve, a magnetic pipeline valve and a high speed rotary shaft seal.
The Efco short cycle vacuum furnace
lnfomtation from EYeiffer In Vakuurninformationen, No 8, the bulletin of the Arthur Pfeiffer Hochvakuumtechnik GmbH, two recent additions to the firms range of turbomolecular numns are described. The TVP 250. first shown at Achema 1967, in June, o@ers a constant pumping speed of 70 -litres/sec (250mYh) over the total working range below ’ lb-l torr. Ultimate pressUres of about 5 x lo+ torr are obtained. Apart from the usual advantages of turbomolecular pumps this model features a novel design of power generator with a dc motor, controlled entirely by solid state circuitry which ensures silent, vibration-free rotation. Where pressures below lo-’ torr are not essential, the model THP 900 offers a constant pumping speed of 260 litres/sec (935 ma/h) below 10m3 torr. Ultimate pressures are below 1Om8torr. The company’s activities in the field of large scale drying plant for transformer production and for the impregnation of cable insulation are summarized with reference to a recent installation in Bratislava, Czechoslovakia, and to the work of their associated company, Pfeiffer Vacuum Engineering (GB) Ltd, Harrow, England. Vacuum Newsletter In June 1967, AEI Ltd (Scientific Apparatus Dept, Barton Dock Road, Urmston,) Manchester issued their second Vacuum Newsletter. one of a series of five. describing their primary vacuum pump model GDRi and presenting some experimental results obtained when comparing the Minimass partial pressure gauge with a BayardAlpert type of gauge. The GDRl is a direct drive, two-stage pump with differential pumping at a nominal speed of 1 litre/sec. Ultimate pressure is 5 X lo-* torr, although 2x lo-& torr is stated to be regularly obtained in routine tests. Other features of the pump include adjustable gas ballast, inlet filter and gravity and pressure drams. A full range of accessories is available, in particular the FT2 molecular sieve filled, foreline trap, which allows roughing of ultrahigh vacuum systems. The pump is noiseless, vibrationless and reliable being designed for equipment such as electron microscopes, large mass spectroand micrometers, x-ray equipment analysers. The helium market Gardner Cryogenics Corporation (2136 City Line Road, Lehigh Valley Industrial Park, Bethlehem, Pennsylvania 18017, USA), have issued two free brochures: “The Channina Helium Market”. a 12-nage report on the growth of the helium markit, the properties and uses of helium and the helium conservation programme; and
“Superconductive Magnet Systems”, a 1Zpage catalogue describing the Company’s products and their “Instant-Quote” system of product specification. The report on the helium market describes the company’s national and international distributions network. usina 130.000-scf tube trailers to transport helium gas and 9,000 gallon trailers or 1,OUO-gallon, air-transportable, low pressure dewars for liquid helium. The ioint enterprises undertaken with the Alamo Chemical Company (a subsidiarv of Phillins Petroleum Comnanv) are outlined. These involve the treatment of natural gas, extraction of liquid natural gas, the extraction and purification of crude helium and the liquefaction of helium.
“Industrial entitled Semiconductors”, “Industrial Components” and “Industrial Valves and Tubes”. A separate equivalents amide is included with the valve and tube guide. Vacuum devices are covered in the “Industrial Components” edition along with capacitors, resistors, ferrite and piezoelectric devices and magnetic materials. Product information is abbreviated to allow ranid annraisal and comnarison of similar product types. Products added since the 1966 issues are listed in italics and volume numbers of the handbooks which contain more detailed product information are supplied. Requests should be made on company headed notepaper to Mullard Ltd, Industrial Markets Division, Mullard House, Torrington Place, London, WCl.
Electron beam technology
Temescal Metallurgical Corporation (2850 Seventh Street, Berkeley, California 94710, USA) offer a free. 1Znacre colour brochure which surveys the evolition of electronbeam technology from early laboratory experiments to the present state-of-the-art. The brochure is well illustrated with graphic representations. Topics covered include the nature of electron beams, the development of gun-target systems, electromagnetic beam deflection, self-accelerating guns and power supplies. Mullard reference guides for 1967/68 The 1967/68 editions of Mullard Ltd’s wide range of industrial components, are now available. Three guides are avadable
Commercial
news
New missile brazing facility at British Aircraft Corporation Missile components are now being brazed in an Efco vacuum furnace in the Guided Weapons Division of British Aircraft Corporation (Operating) Ltd, Stevenage. The furnace, designed and manufactured by Efco-Royce Furnaces Ltd, incorporates the latest features introduced by the Company to reduce the overall brazing cycle with the admission and circulation of 475