Sample liquid filter has closed-circuit filter circuit with two exchangeable filter inserts and reversible pump for return of liquid under sterile conditions

摘要

A liquid filter (1) receives a sample of pre-filtered liquid from a container or pipe for measuring purposes. The filter has a closed-circuit with a first filter insert (4), a liquid pump (27) and a second filter insert (5). The sample is then drawn from the container or pipe through the first filter insert and is then returned to the container or pipe via the second filter insert, or vice versa. Preferred Features: The pump is reversible and has a self-operating reverse action which is activated periodically. The filter inserts may be exchanged for alternative inserts with a different volume flow rating. The filter component parts (2-7) are commonly mounted on a pipe (7) base.