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Publication of NL6601388ApublicationCriticalpatent/NL6601388A/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
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Engineering & Computer Science
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Mining & Mineral Resources
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Life Sciences & Earth Sciences
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General Life Sciences & Earth Sciences
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Geochemistry & Mineralogy
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Geology
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Conveying And Assembling Of Building Elements In Situ
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