X43W two-way cast iron flange plug valve is a rotary valve with a closing part or plunger shape. By rotating 90 degrees, the channel opening on the valve plug is made to communicate with or separate from the channel opening on the valve body to achieve opening or closing. The shape of the valve plug of the plug valve can be cylindrical or conical. In the cylindrical valve plug, the channel is generally rectangular; while in the conical valve plug, the channel is trapezoidal.