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

OBRABOTKAMETALLOV Vol. 23 No. 4 2021 TECHNOLOGY fi lter tubes was established, processing schemes were proposed, the features and key dependencies of the process were identi fi ed, recommendations for the implementation of the method were given, and tests of the operational characteristics of the obtained fi lters were carried out [15, 16]. The physicomechanical prop- erties of polymer materials and their low heat resistance signi fi cantly limit the scope of their application. Metal fi lter elements with a slotted structure obtained by DC do not have these disadvantages. The prin- ciple of obtaining fi ltering slotted metal pipes through cutting of sections of special pro fi les was published earlier [17]. However, for the through-cutting of a metal workpiece by the DC method, the in fl uence of the technological parameters on the shape and geometric parameters of the resulting slots has not been studied. The purpose of this work was to establish the in fl uence of the parameters of the DC , namely the feed and the depth of cut, on the character and shape of the slotted structures obtained by full-depth DC method on copper samples. Research methodology At the previous stages of the research, it was tested and recognized as expedient to use longitudinally corrugated (star-shaped) pipes (Fig. 2), obtained using ball dies [18], as blanks for metal fi lters. Longitudinally corrugated pipes are available for production on an industrial scale using special equipment [19] and are of interest as blanks in the serial production of fi lter pipes. However, their production in itself is a rather complex technological task that should be solved for each standard size and workpiece material. To study the process of full-depth cutting by the DC method and obtain an array of experimental data, processing single corrugations obtained on a metal strip using a special device (Fig. 3) installed on a screw- cutting lathe model 16B16KA was recognized as a more expedient scheme. Fig. 2. Cutting slots on a longitudinally corrugated pipe using the D С method Fig. 3. Scheme of cutting through a single corrugation using a barrel attachment Corrugated strip 2 is wrapped around a drum 5 mounted on a screw-cutting lathe. The tight fi t of the strip to the drum is ensured by the radial movement of the spring-loaded tensioner 4 , in which both ends of the strip are clamped. As an assumption, it was assumed that the tension of the strip did not lead to a change in the geometrical parameters of the strip. In the framework of each experiment, the tool 1 cuts only one of the corrugations of the strip because of pad 3 made of low-pressure polyethylene. In comparison with the processing of corrugated pipes directly, this scheme allows neutralizing the in fl uence of the different heights of the corrugations and radial runout of the pipe on the cutting of slot and simpli fi es control over the process. For each corrugation, the depth of cut is set individually from the touch of the surface of the corrugation with the tip of the cutter, which allows obtaining more accurate experimental results.