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SEMI-AUTOMATIC HYDRAULIC SHIELD FOR TEMPORARY SUPPORTING MINE DRIFTS AND TUNNELS AS WELL AS FOR SIMULTANEOUS SETTING-IN FINAL CIRCULAR CLOSED SUPPORT THEREWITH
SEMI-AUTOMATIC HYDRAULIC SHIELD FOR TEMPORARY SUPPORTING MINE DRIFTS AND TUNNELS AS WELL AS FOR SIMULTANEOUS SETTING-IN FINAL CIRCULAR CLOSED SUPPORT THEREWITH