Wüest M. 51 Wykes M. 82 Yamaguchi M. 17 Ybarra G. 129 Yubero F ...

JUNE 26 MONDAY AFTERNOON
WS-18-MoA-INV.3 CLEANING PROCESSES AND QUALITY CONTROL FOR VAC-
UUM. R J Reid, ASTeC, CCLRC Daresbury Laboratory, Warrington WA4 4AD, UK
Cleaning is an important part of the processing of vacuum components and systems for any level of
vacuum. However, the lower the pressure required, the more stringent the cleaning requirements
must be.
Over recent years, many of the traditional processes used for cleaning have become unacceptable because
of their effect on the environment and, indeed, many have been prohibited by legislation.
In this paper, an outline will be given of the search for the “perfect” cleaning process for UHV and
XHV components which is effective, economical and likely to remain acceptable. We shall discuss
what has become the industry standard use of aqueous detergent based techniques and the use of
some of the newer solvents which have been developed.
Of course, the search for a “perfect” process leads us to pose the question “How do we know when a
system is sufficiently clean?” Some answers to this question will be discussed. This will then lead us
to look at implementation of quality control procedures to ensure that an “as delivered” component
will be satisfactory for purpose.
Examples will be given, including that of a very large XHV vessel currently being manufactured in
Germany.
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