Labyrinth type fixed throttling depressurization part of underwater medicament injection equipment

The utility model discloses a labyrinth type fixed throttling depressurization piece of underwater medicament injection equipment, which comprises a depressurization seat body, at least two threaded depressurization channels are arranged in the depressurization seat body, and the depressurization channels are sequentially sleeved layer by layer. The spiral diameters of the multiple pressure reduction channels are sequentially increased in the direction from the inner layer to the outer layer. Every two pressure reduction channels which are adjacent inside and outside are communicated with each other, and the free ends of the pressure reduction channels on the outermost layer and the innermost layer form an inlet and an outlet respectively. The pressure reducing device has the advantages that the length of the pressure reducing channel can be greatly increased within the limited axial length, so that the stable pressure reducing effect is achieved on flowing medicament flow, the pressure reducing capacity is h