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Priority claimed from FR97794Aexternal-prioritypatent/FR1521519A/fr
Application filedfiledCritical
Publication of BE711679ApublicationCriticalpatent/BE711679A/xx
E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
E21D21/0086—Bearing plates
E—FIXED CONSTRUCTIONS
E21—EARTH OR ROCK DRILLING; MINING
E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
E21D11/006—Lining anchored in the rock
E—FIXED CONSTRUCTIONS
E21—EARTH OR ROCK DRILLING; MINING
E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D17/00—Caps for supporting mine roofs
E21D17/02—Cantilever extension or similar protecting devices
E21D17/06—Cantilever extension or similar protecting devices for use in drifting galleries