MAN-HOLE Russian patent published in 2007 - IPC B65D90/10 E02D29/14 

FIELD: servicing facilities.

SUBSTANCE: invention relates to facilities designed for servicing high-pressure sealed equipment, such as boilers, collectors, recuperators. Proposed man-hole has oval cover. Said cover is arranged inside reservoir and is attached to movable support welded to inner surface. Central part of cover is made additionally from thin sheet in form of ellipse being pointed by convex surface inside reservoir. Stops and ribs are welded on concave surface of cover perimeter. Detachable oval half-rings provided with slots are arranged on ribs. Pressure ring is arranged on end face of oval collar secured in hole of reservoir. Detachable half-rings are clamped, together with pressure ring, by fasteners and form cover sealing device. Oval gasket is fitted n groove on end face surface of cover.

EFFECT: reduced mass of man-hole at increased tightness.

3 dwg