Reducing rolling rounding device for stainless steel pipe ports

The invention discloses a reducing rolling rounding device for stainless steel pipe ports, which comprises a lathe bed, a workpiece stopping mechanism, a workpiece positioning mechanism, a rolling wheel propelling mechanism, a rolling wheel transmission mechanism, a rolling wheel moving mechanism and a PLC (programmable logic controller). A workpiece which is conveyed into a roll surface between a left carrier roll and a right carrier roll in a carrier roll support (1) and enters a workpiece rolling position is positioned and stopped by the workpiece positioning mechanism and the workpiece stopping mechanism, the rolling wheel transmission mechanism is shifted into the workpiece rolling position by the rolling wheel moving mechanism, an upper rolling wheel (23-3) and a lower rolling wheel (23-3) in the rolling wheel transmission mechanism are driven by an upper propelling nut (23-10) and a lower propelling nut (23-10) to enter the carrier roll support and press rolling positions of the workpiece, the upper pr