摘要 |
<p>A unit (4) for reducing the emission of pollutants contained in exhaust gas is disclosed. It comprises a frame and a stack (2) comprising a plurality of layers (20) of corrugated sheet material. The stack (2) is formed by alternately folding back and forth an unfolded strip (1). The unfolded strip (1) has a length (100) corresponding to the length (200) of the layers (20) and a width (101) corresponding to a multiple of the width (201) of the layers (20). The corrugations (10) of the unfolded strip (1) run in a direction including an angle ( ± ) different from zero with the direction of the length (101) of the strip (1), so that after folding the strip (1) the corrugations of the adjacently arranged layers (20) come to lie on one another crossing each other at a crossing angle ( ² ) which is twice as much as the angle ( ± ). The folds (21) connecting the adjacently arranged layers are welded to the side walls (31, 33) of the frame along welding seams (40, 41).</p> |