Swivel closure for inspection cover - has evenly stressed locking bolt with frame and cover bearing face

摘要

The bolted closure prevents traffic impact from eventually springing the inspection cover from its housing and the swivel (6) creates equal forces on the bolt, so that it is not subject to bending stresses, only straight tension. A threaded bolt (3) passes through the cover (2) and has the swivel on its lower end, a pin (4) stops the pivot being accidentally unthreaded. When the bolt is turned, the swivel rises until one swivel edge stop (8) presses against the frame (1). At the same time the other swivel edge stop (11) presses against the base of the cover.