SIMULATION OF THE PROCESS OF HARDENING A LARGE TRAPEZOIDAL THREAD USING ROLLER R UN
Screw pairs of machines with a tapezoidal thread experience significant loads that cause the formation and development of cracks at the base of the thread projections and lead to its destruction. It is possible to increase the cyclic strength through the use of a combined cutting-deforming method, which includes the preliminarv formation of a cavitv bv cutting and final processing in the form of rolling with a roller. The paper studies the process of hardening trapezoidal threads using the rolling of a pre-cut profile with a roller. Modeling of the running-in process was carried out using the finite element method based on the Deform-3D software package. Three options for the shape of the precut thread root profile were considered: trapezoidal, similar to the finally formed profile; trapezoidal with a triangular end section; trapezoidal with a terminal parabolic section. For each variant, the stress intensity a<sub>i</sub>, the strain intensity e<sub>i</sub>, and the relative cross-sectional area of the deformation zone a<sub>y</sub> with maximum hardening were determined. It has been determined that the most effective is the technology, which includes the preliminary formation of a groove in the form of a trapezoid with a triangle and subsequent rolling with a roller.