Straight-flow Y-shaped stop valve

The utility model provides a straight-flow Y-shaped stop valve, which comprises a sealing device, a functional device and a pipeline connecting device. The sealing device comprises a valve cover, a valve rod, a valve body, a packing, a packing seat, a sealing ring, a four-element ring and a containment ring, wherein the valve cover is arranged on the valve rod in a surrounding way, and a columnar structure is arranged in the center of the valve cover; the packing and the packing seat are arranged between the columnar structure and the valve rod; a groove is formed in the edge of the upper surface of the valve cover, and the sealing ring is arranged in the groove; the sealing ring is tightly pressed by one end of the four-element ring, and the other end of the four-element ring is fixedly arranged in the groove of the valve body; and the containment ring is fixedly arranged at the outer side of the columnar structure of the valve cover, and is in axial bolted connection with the valve cover. The functional dev