Conversion nozzle installed on standing pouch and standing pouch assembly

The utility model discloses a conversion nozzle installed on a self-standing bag and a self-standing bag assembly. The conversion nozzle installed on the self-standing bag comprises a fixing part, a connecting nozzle and a connecting part connecting the fixing part and the connecting nozzle. The fixing part is used for being in threaded connection with an external thread on the suction nozzle of the standing pouch, and the external thread on the suction nozzle is used for being in threaded connection with a cap on the suction nozzle; the connecting nozzle comprises a first end and a second end parallel to the first end, and the outer diameter of the first end is smaller than that of the second end; the second end of the connecting nozzle is connected with the fixing part through the connecting part; the fixing part, the connecting part and the connecting nozzle are arranged in a communicating manner; the stand-up pouch fixing device can adapt to stand-up pouches of different specifications, stand-up pouches o