This paper describes the working theory

construction design

technology rules and inspection accuracy of the precision stepper ball screw nut. The stepper ball screw nut has been used in a beam monitor system of Beijing proton synchrotron. The step is 0.5mm;the step accuracy 0.01mm;the step velocity 6mm/s.The screw nut is of double nut tube type which is single tube 2.5 circuits. The screw shaft diameter is 20.5mm;the lead 5mm;the ball diameter 3.175mm;the position accuracy 4.7μm;the repeat position accuracy 2.0μm.