Improvement and Research of a New Combined Method for Producing Screw Fittings Using Computer Modeling

This paper presents the results of modeling a combined process of radial-shear rolling and pressing in order to obtain a reinforcing profile at different rotation speeds of the screw matrix. The parameters of the stress-strain state in the zones of radial-shear rolling and the formation of a screw profile in the matrix on the surface and axial parts of the workpiece were analyzed. It has been established that the forced rotation of the screw matrix not only helps to increase the process performance, but also plays an important role in preventing the defects formation. The maximum value of the equivalent strain is achieved in a fixed matrix, the higher the rotation speed of the matrix, the lower the values of the equivalent strain. At the same time, in the case of a high rotation speed of the die, the minimum strain level is 10 approximately. Stress state analysis has shown that this deformation scheme creates a high level of compressive stresses, which are dominated by tensile stresses.