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Publication of NL6607355ApublicationCriticalpatent/NL6607355A/xx
E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D23/00—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
E21D23/0052—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor with advancing shifting devices connected therewith
E—FIXED CONSTRUCTIONS
E21—EARTH OR ROCK DRILLING; MINING
E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
E21F13/00—Transport specially adapted to underground conditions
E21F13/08—Shifting conveyors or other transport devices from one location at the working face to another