Disk seat and relief valve

The utility model discloses a disk seat and relief valve, disk seat include valve seat body, valve seat body's one end is equipped with the entry, the other end is equipped with the export, be equipped with the intercommunication in the valve seat body the fluid passage of entry and export, fluid passage connects gradually on including the axial first passageway and second channel between entry and the export, the interior of first passageway is connected without leave the first end of entry is to the connection the second end of second channel reduces gradually, and, is the inner wall contained angle alpha of first passageway 18 21. The utility model discloses a disk seat, through the improvement setting of inside circulation passageway, the inner wall that makes the circulation passageway reduces the flow resistance according with the distribution curve that fluid speed attenuates on the inclination at the straight line in shape, improves fluid speed, can effectual improvement have the emission of the relie