The principle of jet weft insertion in water jet loom is similar to air jet weft insertion. It uses clean water as the medium to guide the weft, and produces friction and traction force on the weft by spraying water.

The water-jet loom is suitable for the weaving of hydrophobic synthetic and glass filaments.Water spraying weft diversion requires water quality and sometimes needs special water treatment device.

Because impurities contained in water will corrode and block pumps, pipes and nozzles. It will affect weft insertion, resulting in fabric defects, even will damage machine parts and shorten machine life.