Rotary-vane vacuum pumps

Rotary-vane vacuum pumps

Vacuum News Newliterature Vacuum diffusion pumps The latest brochure from Leybold-Heraeus Ltd is “Diffusion Pumps”, issued as is usual with this com...

125KB Sizes 2 Downloads 180 Views

Vacuum

News

Newliterature Vacuum diffusion pumps The latest brochure from Leybold-Heraeus Ltd is “Diffusion Pumps”, issued as is usual with this company as a loose-leaf publication that can be inserted into the main catalogue sprung binder. Its 42 pages first give an introduction to the theory of diffusion pumps, and then list such varieties as oil diffusion, oil ejector, mercury diffusion, water jet, steam ejector and turbomolecular pumps. It also lists liquid nitrogen refilling units and feed pumps, and many ancillary components for pumping, such as baffles, cold traps and safety devices. Leybold-Heraeus Ltd Circle number 50 on Reader Enquiry Service card

Rotary-vane vacuum pumps A new 28-page brochure from Leybold-Heraeus Ltd describes their Trivac single and double stage ‘A’ series vacuum pumps, and the general purpose laboratory pump, the Minni-A. The rotary-vane vacuum pumps described are direct driven by a flanged-on electric motor and incorporate an integral oil anti-suck-back and airing device. Pumping speeds go from just less than 1 to 60 m3/h. The brochure is also ready punched for insertion, if desired, into the Leybold catalogue binder.

I--Invhnlc-l --‘-

Hegeu:

L!d

the role of institutions in encouraging co-operation, and stress that “the more useful the likely outcome of co-operation, the more difficult collaboration becomes”. Nonetheless they feel new institutions are needed to put policies into practice but they must avoid past mistakes. Other contributors describe their successful attempts in developing co-operative research and one (Prof Thiebault, Committee on the Challenges of Modern Society, NATO) explains how it is possible to get others to do research without paying for it. The rest of the Symposium concentrated on industrially based European R Et D and Dr Newth (ICI Europa) tells how ICI went about creating a European R 8 D Laboratory, and Dr Wilkinson (Head of Isleworth Laboratories, Unilever) outlines the problems of organizing research workers in multi-national laboratories. Fnllnwinn (rien~~tv B-AC) analvses _.._. . J thk . . .._ Alan .._.. Greenwood \--r--r chairman< .-I -..-.r--the various ways European nations work together in building aircraft, and comes out strongly in favour of the single project company as the best means of co-operation without confusion of purpose. Including a full record of the discussion of the 9 papers the proceedings should be a useful picture of recent and possible developments in European R Et D cooperation. The Research and Development Society Circle number 53 on Reader Enquiry Service card

Circle number 51 on Reader Enquiry Service card

Mass spectrometry A booklet is available from VG-Micromass Ltd which tells the story of the growth of Micromass from six founder members in 1970. Rapid expansion continues and next year a second factory is to be opened at Knutsford. The instrument range, which includes both sector and quadrupole units, is divided into product groups covering the following applications : Organic mass sn~rtmmeterc-fnr ami._ grgct~~ra! &$erminati~ns. lr __.._..._._._ ._. nn _.. lit-w ...._ GCIMS _ _ , .. ._ I. Small mass spectrometers-for gas analysis and low level impurity monitoring. Isotope mass spectrometers-for stable isotope analyses. Research mass spectrometers-Custom built for individual requirements. One of the most recent additions to the range is the Organic Micromass 128 which is designed to meet the requirements of the GC/MS market. The instrument combines high resolution fast scanning with nanogram sensitivity. A wide range of accessories, including on-line computer data systems and a double focusing conversion, are available for the organic Micromass 12B. VG-Micromass Ltd Circle number 52 on Reader Enquiry Service card

European co-operation in research and technology The Research and Development Society’s Symposium last April provided a forum for a number of experts on European research and technological co-operation to talk about their experiences and air their hopes and fears for the future. The proceedings of the Symposium, published on 25 September, are a useful source of information on how people already co-operate and how this might develop in future. Chris Layton (EEC Commission Director of Advanced Technology Industries) and Prof Chris Freeman (Science Policy Research Unit, University of Sussex) describe the development of policies and 460

Exhaust heads Holden Et Brooke Ltd, Manchester, have recently produced a new leaflet containing technical and general information about their range of exhaust heads. The exhaust head is designed to protect the exterior of buildings from the harmful effects of steam ejection to atmosphere. It is fitted to the end of a vertical exhaust pipe and thus breaks the beat and muffles the noise of escaping steam, whilst effectively retaining the moisture and grease for draining. The body is strongly constructed using welded, leak-proof seams and the area within the head prevents any back pressure during service. Inlet bore sizes range from 1 to 30 in. Holden Et Brooke Ltd Circle number 54 on Reader Enquiry Service card

New bellows valves booklet A Ifi-n=nn hn~Cl~+ “‘w_.,‘Y”‘y Ancrrihinn I V-p”Y.2 “““..,I&

N,,nm m.“p#”

mzan,,ell\,_nncaratm, “‘Y”““‘., .ay-....l-

valves is now available from Techmation

bp!!a\??

Ltd.

The bellows seal is ideal for extreme environments. There are no conventional packings such as elastometers, TFE or asbestos which can degenerate rapidly at high or low temperatures, or when in contact with corrosive or radioactive fluids. Bellows valves, on the other hand, are used, typically, with liquid-metal systems at 9OO’C or cryogenic systems near absolute zero. The booklet outlines the bellows valve principle and describes some of the standard manually-operated valves in the Nupro range including general purpose valves; toggle, critical service, and hermetically-sealed valves, and metering valves which incorporate a micrometer for precision settings. Techmation Ltd Circle number 55 on Reader Enquiry Service card