Designed for operation without an external vacuum system; and

The invention provides a vacuum system (12) comprising a plurality of vacuum chambers (14, 16, 18, 20) connected in series and a vacuum pumping arrangement (10) for differential pumping the chambers.

A method for determining an overall leakage rate of a vacuum system can be operated continuously or cyclically.

The extensive production areas are equipped with a Busch centralised vacuum system supplying 30 packaging lines in several buildings.

The invention relates to a holding device for a vacuum system having an elevating platform (1) which can be displaced between a lower end position and an upper end position.

A vacuum source is controllably connected through a valve (16) to the reservoir to draw gas out of the liquid held within the reservoir.

A de-aeration port (6) is present at the top of the de-aeration unit and a de-aeration line (7) connects the milk glass to a vacuum system (not shown).

In order to maintain a negative pressure in the container (1), and to extract by suction the resulting vapour/gas mixture, the device is fitted with a vacuum pump, as well as an outlet pipe (6) through which the purified water is drawn off.