The unique design of 3M DF Series filter bags provides end-users measurable performance advantages.  Combining graded porosity media with concentric cylinder geometry results in 62% more filtration area and 67% lower fluid hold-up volume.  This extends filter service life by up to 4 times, lowers energy usage and reduces product loss and labor cost.

The DF Series is constructed with two concentric cylinders bonded to ring plates at the top and bottom, providing superior structural support and eliminating issues that standard bags have with ruptures and bypass. Fluid enters the annular space between the two cylinders and crosses through the inner cyclinder from out-to-in and the outer one from in-to-out. This configuration reduces fluid hold-up and increases the media surface area available for filtration.

Each cylinder is covered with two layers of media. The outer layer is more open, and the inner layer is tighter. This graded porosity allows the media to hold more contaminant, while allowing fluid to pass with less resistance (lower pressure loss).  Additional surface area and graded porosity both contribute to increased filter service life and lower energy requirements.