Abstract: The invention can be used in pipelines, any devices, man holes and arrangements, at any pressures and working conditions for closable large-diameter pipes. The aim of said invention is to improve the operating reliability of a gate. The inventive gate comprises a lid consisting of a flange and a bottom caved in a pipe, wherein a sleeve provided with a supporting ring is welded to the bottom, arresting elements in the form of sectors insertable into the circular boring of the tube, when they are radially displaced on the flange along clamping bolts and on the supporting ring by the action of the inclined face of a drive nut, are arranged on the end face of the flange and on the supporting ring. The nut is embodied in the form of a truncated pyramid provided with T-slots embodied on the side surfaces thereof.