Optimal control of screwing speed in assembly with thread-forming screws

This paper presents a mathematical model that allows for the best thread-forming speed to be calculated based on a detailed efficiency function. The optimum thread-forming speed is calculated at several stages of the assembly process, and thus allows the creation of flexible control systems for automatic assembly devices. Controlling screwing speeds according to the suggested rule can reduce the torque (required to assemble threaded connections) by 15-20%.