OBRABOTKAMETALLOV TECHNOLOGY Vol. 24 No. 2 2022 where xР0cut_m and yP0cut_m are the coordinates of the point P0cut_m in BCS general for the m-position of the ISCD, determined by the formula: 1 _ 0 _ 0 _ 1 _ cos( ) sin( ) . sin( ) cos( ) 0 Ppo m P cut m m m P cut m Ppo m m m x x N y y (12) 3. From the obtained distances the minimum value is selected and is set as _ max I p h . 4. Points k cut P are calculated for all positions of the ISCD with a cutting tool overhang equal to _ max I p h . Based on the obtained points k cut P , a B-spline is constructed, which determines the maximum achievable shape of the surface section contour after machining at a given transition (line 5, Fig. 4). The calculated value _ max I p h determines the maximum allowance to be removed at the I-transition, which provides machining of the surface to the dimensions of an inscribed circular cylinder (without gouging). Calculation of the maximum cutting depth From the adopted processing scheme and strategy for setting the working strokes it follows that the actual cutting depth is a variable and depends on the ISCD motion trajectory along the base surface section, as well as on the distortion of the surface shape in the section being processed. Thus, it is possible to exceed the maximum permissible cutting depth max per t (per. – permissible), at which the cutting tool and/or the processing module will fail. In order to prevent this failure it is necessary to calculate the maximum achieved cutting depth max k t (Fig. 4) in each kth cross section of the processing area for the current parameters of the limit value of the cutting tool extension _ max I p h to the technological transition. The value max k t in the kth section on the basis of the previously given model of the forming process is calculated according to the following algorithm. Fig. 4. Schematic diagram of calculating the depth of cut in the kth section 1 – processing module; 2 – base section contour; 3 – inscribed circular cylinder contour; 4 – surface contour before machining at the current transition; 5 – calculated surface contour after machining for the current transition; zi – is the calculated maximum machining allowance for the current transition and the position of the NOUK
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