Three-eccentric center butterfly valve

The invention discloses a three-eccentric center butterfly valve which comprises a valve assembly, a valve plate assembly, a valve rod assembly, a second sealing assembly and a third sealing assembly.The valve rod assembly is connected with the valve plate assembly to drive the valve plate assembly to rotate synchronously and comprises a valve rod, a positioning hole and a connecting mechanism, the valve rod is rotatably arranged in two communicating seats in a penetrating mode, one end of the valve rod extends out of the valve body, and the positioning hole is formed in the valve rod; the connecting mechanism is matched with the positioning hole so as to connect the valve rod and the valve plate assembly; the end, extending out of the valve body, of the valve rod is defined as the outerend of the valve rod; and the second sealing assembly and the third sealing assembly are arranged in the two communicating seats correspondingly so as to seal the valve rod and the valve body. In theway, only small holes need