the valve body divided into left and right body,Y type cut through structure is employed to make low flow resistance and difficult to scale.the valve body can composed of left body and right body,equipped with valve seat in the joints of both bodies.the bolts of both bodies can be taken apart for cleaning, repair and replacement when maintained.the protection plate with hard alloy is equipped at the position which injured hardnest in the wash of the body inner, with which can prevent the body from the scour & corrosion of medium when opening the valve so as to prolong service life of the valve.Hard alloy is bead welded between the sealing surfaces,which features high hardness, in which sphere sealing surface is adopted for the disc while cone –shape sealing surface with ultra-small surface for the seat,thus one kind of linear sealing ( enjoys excellent sealing effects) is formed between the disc & the seat, additionally,it can also prevent from scabbing.Due to its upper seal,it can protect from filling when full open,equipped steering device at the body outside,in which has no contact with the medium,so as to avoid block at the steering parts like gate valve.the valves are widely used in chemical fertilizer, mining, metallurgy, aluminum oxide and other industries.