MANHOLE COVER CLOSED AND FIXED WITH A MANHOLE FRAME BY A PACKING RING HAVING A PROTRUDED FIXING RIB FITTED IN A CONNECTING GROOVE OF A MANHOLE FRAME

摘要

PURPOSE: A manhole cover closed and fixed by a packing ring is provided to prevent the infiltration of the inside of a manhole with foreign matters and rainwater using a packing ring with improved sealing ability. CONSTITUTION: A connecting groove is formed along the upper inner circumference of a manhole frame(20). A packing ring(30) having a protruded fixing rib(31) is forcibly fitted in the connecting groove of the manhole frame. Two inclined portions(12) and fixing grooves(11) are formed on the outer circumference of a manhole cover(10). The fixing rib of the packing ring is inserted to the fixing grooves by elastically interlocking by the inclined portions.