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
Landscapes
Engineering & Computer Science
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Mining & Mineral Resources
(AREA)
Life Sciences & Earth Sciences
(AREA)
General Life Sciences & Earth Sciences
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Geochemistry & Mineralogy
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Geology
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Devices Affording Protection Of Roads Or Walls For Sound Insulation
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Deplacement d'un objet articule virtuel dans un environnement virtuel en evitant les collisions internes entre les elements articules de l'objet articule
Machine permettant de faire pivoter autour de leur axe des tubes de section rectangulaire ou carree de poids eleve et de grandes dimensions,en vue de leur usinage.