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Bakeable ultrahigh vacuum chambers
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Manufacturers and others Manufacturers and others are invited to submit information for inclusion in this feature, addressed to the Vacuum News Editor, Vacuum, Pergamon Press, 4 & 5 Fitzroy Square London Wl.
Contents Technical
and industrial
Commercial
developments
news
Appointments
Technical
and industrial
543
Bakeable ultrahigh vacuum chamber - control of freezedrying - electron beam gun -welding chamber-chamber for sodium centrifuge - ionization gauge - leak testing ultrasonic leak detector - thin film monitor - thin film evaporator - pneumatic hopper feeders - optical fiats oil sealed rotary pumps
547
Apollo test chamber - electron accelerators NINA - new Company - Dr Becker honoured
548
V/A Corp -
AEI Electronics
developments
Bakeable nltrahii vacuum chamber Edwards High Vacuum Limited has produced a versatile, easily demounted stainless steel chamber, 1Cinch diameter x 20-&h high, for general purpose ultrahigh vacuum applications. The chamber is made in two sections the main flange beiig adaptable for either of two types of sealing. For the very lowest pressures gold or indium wire can be used depending on the baking temperature requirements. For less exacting work two concentric “0’‘-ring grooves are provided to suit standard Viton “0’‘-rings, with a pump-out port so that the interspace between the rings can be evacuated by an auxiliary pump. Recent intensive studies at Edward’s research laboratories have shown that by this means the diffusion of atmospheric gases through the inner “0’‘-ring, which usually limits the ultimate vacuum, is prevented. By mild baking up to 150°C the outgassing from the Viton “0’‘-ring can be reduced to such a low value that pressures in the region of lo-lo torr can still be achieved. The chamber is made of welded EN58F stainless steel and its final assembly includes a vacuum brazing operation at over 1000°C which ensures highly efficient degassing of the envelope as well as complete sealing of all welded seams and internal crevices. Leak tightness is guaranteed to better than 5x 10eg torr litre/sec. A wide range of flanged ports can be provided for the attachment of ionization gauges, bakeable windows etc using gold wire seals which have proved very reliable and easy to make in a vertical or horizontal plane. Electrical lead&roughs for thin film or similar work can be added to the lower half of the chamber to suit operational needs. The chamber can be fitted to the new automatic ultrahigh vacuum pumping unit recently introduced by Edwards High Vacuum, but it is equally suited to being pumped by any combination of diffusion, ionization or getter pumps. The top left hand flanged port of the chamber illustrated is fitted with an Edwards experimental helium cry0 pump. Edward5 High Vacuum Limited, UK Circle number 50 on Reader Enquiry Service card
New ultrahigh vacuum chamber from Edwards
synchrotron
Manufacturers and others Manufacturers and others are invited to submit information for inclusion in this feature, addressed to the Vacuum News Editor, Vacuum, Pergamon Press, 4 & 5 Fitzroy Square London Wl.
Contents Technical
and industrial
Commercial
developments
news
Appointments
Technical
and industrial
543
Bakeable ultrahigh vacuum chamber - control of freezedrying - electron beam gun -welding chamber-chamber for sodium centrifuge - ionization gauge - leak testing ultrasonic leak detector - thin film monitor - thin film evaporator - pneumatic hopper feeders - optical fiats oil sealed rotary pumps
547
Apollo test chamber - electron accelerators NINA - new Company - Dr Becker honoured
548
V/A Corp -
AEI Electronics
developments
Bakeable nltrahii vacuum chamber Edwards High Vacuum Limited has produced a versatile, easily demounted stainless steel chamber, 1Cinch diameter x 20-&h high, for general purpose ultrahigh vacuum applications. The chamber is made in two sections the main flange beiig adaptable for either of two types of sealing. For the very lowest pressures gold or indium wire can be used depending on the baking temperature requirements. For less exacting work two concentric “0’‘-ring grooves are provided to suit standard Viton “0’‘-rings, with a pump-out port so that the interspace between the rings can be evacuated by an auxiliary pump. Recent intensive studies at Edward’s research laboratories have shown that by this means the diffusion of atmospheric gases through the inner “0’‘-ring, which usually limits the ultimate vacuum, is prevented. By mild baking up to 150°C the outgassing from the Viton “0’‘-ring can be reduced to such a low value that pressures in the region of lo-lo torr can still be achieved. The chamber is made of welded EN58F stainless steel and its final assembly includes a vacuum brazing operation at over 1000°C which ensures highly efficient degassing of the envelope as well as complete sealing of all welded seams and internal crevices. Leak tightness is guaranteed to better than 5x 10eg torr litre/sec. A wide range of flanged ports can be provided for the attachment of ionization gauges, bakeable windows etc using gold wire seals which have proved very reliable and easy to make in a vertical or horizontal plane. Electrical lead&roughs for thin film or similar work can be added to the lower half of the chamber to suit operational needs. The chamber can be fitted to the new automatic ultrahigh vacuum pumping unit recently introduced by Edwards High Vacuum, but it is equally suited to being pumped by any combination of diffusion, ionization or getter pumps. The top left hand flanged port of the chamber illustrated is fitted with an Edwards experimental helium cry0 pump. Edward5 High Vacuum Limited, UK Circle number 50 on Reader Enquiry Service card
New ultrahigh vacuum chamber from Edwards
synchrotron