Abstract: Disclosed is a butterfly valve capable of controlling a flow of a fluid according to a rotation of a disk. The butterfly valve includes a body provided with an inner space having two open ends; a disk unit having a disk rotatably installed at the inner space, and configured to selectively open and close the inner space according to a rotation of the disk; a first seat portion protruding from an outer circumferential surface of the disk; a second seat portion protruding from an inner circumferential surface of the body, and arranged to face the first seat portion; and a sealing unit mounted to the body, and formed to contact the first and second seat portions such that a gap between the outer circumferential surface of the disk and the inner circumferential surface of the body is sealed. Under this configuration, the butterfly valve may have an enhanced reliability under low and high temperatures and a high pressure.

Abstract: Disclosed is a butterfly valve capable of controlling fluid flow according to rotation of a disc. The butterfly valve includes a valve body having an inner space of which two end portions are open; first and second discs disposed to face each other at the inner space, installed to be rotatable between an open state and a closed state of the inner space, and configured to selectively open and close the inner space; first and second sealing members mounted to the valve body, and configured to contact the first and second discs, respectively in the closed state; and a disc controlling apparatus configured to move the first and second discs to a direction contacting to or spacing from the first and second sealing members in the closed state. Under this configuration, durability and a sealing function may be enhanced.

Abstract: A butterfly valve comprises a valve body, a seat ring mounted on a flow passage of the valve body, a disc rotatably mounted to the valve body and configured to open and close the flow passage by being attached to the seat ring; and a driving device configured to linearly move and rotate the disc so as to prevent interference between the disc and the seat ring when the flow passage of the valve body is open and closed.