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E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
E21D15/14—Telescopic props
E21D15/16—Telescopic props with parts held together by positive means, with or without relative sliding movement when the prop is subject to excessive pressure
E21D15/24—Telescopic props with parts held together by positive means, with or without relative sliding movement when the prop is subject to excessive pressure with axial screw-and-nut, rack-and-worm, or like mechanism
Landscapes
Engineering & Computer Science
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Mining & Mineral Resources
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Mechanical Engineering
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Structural Engineering
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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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Hooks, Suction Cups, And Attachment By Adhesive Means
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Cale deplaçable le long d'un profile et rabattable par pivotement contre celui-ci pour chaque pneu d'un vehicule routier porte par une unite de transport