Apparatus for sucking away a measuring gas from a process gas chamber under vacuum

摘要

The apparatus includes a probe extending into the process gas chamber and a pump which sucks away the measuring gas and forces it through a gas preparation into a gas analysis unit. It further includes a filter. The probe (2) is provided with a filter (3) capable of retaining particles larger than 4 mu m. The vacuum pump (5) is a dry running multistage vacuum pump. A ball valve (9) is located in the suction line (4) between the probe and the pump. A flushing unit (10) is connected by means of a further ball valve (11) to the suction line between the ball valve (9) and the probe (2). The purpose of this unit is to provide when necessary the probe with compressed air.