The quality requirements for pipeline fittings for NPPs and oil and gas facilities have become more stringent recently, which is related to ensuring their safe operation life. When manufacturing parts using subtractive machining technologies, special importance is attached to accuracy indicators of linear-angular dimensions and surface shapes. This study examines ways to optimize dimensional turning using the example of a “separator” part on a multifunctional CNC turning and milling center MULTICUT 630/2000S. Operations of designing and optimizing the production of parts are increasingly determined by the results of simulation modelling, virtual models, which, in fact, are an integral part of technological processes. In this work, simulation modelling is performed on simulators with CNC Sinumerik 810/840D/Operate Turn. This procedure is a simplified version of the Weiler-Atherton clipping algorithm as applied to stock removal turning. In addition to the algorithm, additional modules for dynamic corrections of control programs are proposed in order to guarantee the requirements of design documentation for accuracy in the conditions of a dynamic SPID system: machine – fixture – tool – part. The cutting speed, depth of cut and tool feed in turning have the greatest influence on the stock removal process from the technological control parameters. Modules of dynamic corrections of control programmes allow to estimate quite accurately the influence of control factors in turning (cutting speed, depth of cut and feed) on cutting force and machining accuracy.