The invention discloses a flow
drill screwing process parameter conversion key point self-adaption switching method. The flow
drill screwing process parameter conversion key point self-adaption switching method comprises the steps of a calibration stage, specifically, a pressing block of flow
drill screwing equipment is made to contact with a guide rod in the same plane, and a relative position measured by a coded ruler is taken as a
null point; a cap seeking stage, specifically, after a riveting process begins, the actual pressure F3 of the guide rod is gathered, when the F3 = Faverage + a, arelative position L3 corresponding to the pressure point F3 is recorded and is taken as a cap seeking conversion point position, and then switching to
puncturing stage parameters is performed; and apuncturing stage, specifically, the
maximum pressure Fmax of the guide rod is monitored in the
puncturing stage, then the descending pressure F4 of the guide rod is monitored, when the F4 = Fmax * b%,a relative position L4 corresponding to the pressure point F4 is recorded, and if the L4 is less than L3 - D2, the L4 is taken as a
puncturing conversion point position, and a tapping stage is performed. According to the flow drill screwing process parameter conversion key point self-adaption switching method, by means of gathering of riveting force and displacement signals and in combination with a
control logic, cap seeking and puncturing conversion points are accurately identified.