Patent ID: 8840085

Claim:
A multi-seal knife gate valve coupled with a pipe, consisting of: a valve body coupled with the pipe in which the fluid flows, the valve body having a disk recess at the bottom of an inside of the valve body; a disk inserted into the valve body to move vertically to open or close a passage through which fluid flows, wherein the disk is positioned in the disk recess when the disk moves to the bottom of the valve body; a valve seat pressed against the disk so as to maintain a tight seal, the valve seat comprising a metal seat and a rubber seat to maintain the tight seal; a seat ring comprising a cylindrical body at one side and a radial flange at the other side, wherein the rubber seat and the metal seat are installed on the end of the one side of the seat ring; and a stopper provided on the disk recess in order to allow the vertically-moving disk to be stopped at the disk recess and concurrently press the disk against the valve seat, wherein in the state of the disk not being in contact with the stopper, the rubber seat is installed such that the rubber seat is spaced apart from the disk by a distance, wherein the disk, the rubber seat and the metal seat are positioned in a way that the flow of the fluid presses the disk toward the rubber seat when the disk closes the passage.