The BOLLFILTER Automatic TYPE 6.60/6.61 key to solving the task is in the concept, the filter is designed to enable simultaneous filtering and backflushing independently of one another and without interrupting operation. The compact filter body houses a number of individual filter chambers. Each chamber is fitted with its own filter element assembly providing a large filtration surface area and high free cross-sections giving a very low clean pressure drop. Due to their robust construction the filter elements will withstand high operating differential pressure and the individual filter chambers with different filter elements work together as an integrated unit providing consistent quality and security. The concept of the multi-chamber filter resulted in a cyclic mode of operation during the filtration process - one chamber containing a dirt loaded filter is isolated from the pro cess and backflushed whilst simultaneously a filter chamber with clean elements (earlier backflushed and held in reserve) takes over the task of the isolated chamber. The individual filter chambers are subjected to the filtering and backflushing process one after the other in sequence. As a result, filters never reach critical contamination levels. Backflushing can be actuated in accordance with differential pressure and/or time. The cleaning (backflushing) process is extremely fast, thorough and places less pressure on the fabric used for the mesh by utilizing compressed air. System pressure remains almost constant throughout and the unit only requires a minimal amount of cleaning fluid.