Arrangement of the Return line filter "in the secondary flow", i.e. the filter is placed parallel to a throttle so that only one part of the returning oil flow is filtered (Figure T 7). This arrangement is selected when the oil flow becomes very large at periodic intervals (e.g. in the case of feedback from cylinders with a large ratio of piston areas), but the Filter should be small. It has the disadvantage that unfiltered oil also reaches the container.
Figure T 7: Partial flow filtration (return line filter in the bypass)