Influence of the parameters of deforming cutting on the features of the resulting slotted filter structures

OBRABOTKAMETALLOV Том 23 № 4 2021 TECHNOLOGY The range of cutting depth was chosen so that it included the boundaries, on the one hand, of the begin- ning of the full-depth cutting of the material, and on the other hand, the beginning of the destabilization of the process of obtaining slots (irregular or continuous stripping of slot walls). In the absence of slot wall stripping, the depth of cut was increased until the tip of the tool touched the lower point of the corrugation. At the selected major and minor tool cutting edge angles, the feed 0.4 mm/rev, according to formula, corresponds to a slot width of 151 μ m. With a further increase in the feed, the stability of the process, ac- cording to the general patterns of the DC , will only increase, up to the reaching the feeds at which a mere squeeze of the material is observed instead of the DC . Therefore, the feed value 0.4 mm/rev was taken as the upper boundary and the main attention was paid to obtaining structures with a smaller inter fi n gap (and greater fi ltration fi neness). The lower limit of the considered feeds (0.05 mm/rev.) is due to the technologi- cal capabilities of the equipment used. Results and discussion According to the results of 167 experiments at various values of feed and depth of cut, among all the results obtained, 6 groups were identi fi ed, based on which the entire set of considered combinations of DC parameters – feed and depth of cut – was divided into several areas (Fig. 9) depending on the degree of suitability of the resulting structures for fi ltration. The diagram shows the most frequent result for each combination of parameters for several experiments. Each of the result groups is described below. Group “0” – absence of the full-depth cutting . Absence of the full-depth cutting of the corrugation was noted at cutting depths exceeding the nominal thickness of the belt, which is explained by the error in the thickness of the belt and elastic deformations of the corrugated pro fi le. Group “1” – uniform slots (Fig. 10). This group forms on the diagram (Fig. 9) the area “ A ” (highlighted in green), which is the target for the manufacture of fi lter elements. The DC process is stable; the slots have Fig. 9. Diagram of typical structures obtained under different combinations of tool feed and depth of cut: 0 – Absence of the through cut; 1 – Uniform slots; 2 – “Twinning”; 3 – Stripping of every second slot wall; 4 – Non- regular or complete stripping of slot walls; 5 – Uniform slots with a formed “skirt”; 6 – Uniform slots with a “skirt” opened incompletely