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E21C29/00—Propulsion of machines for slitting or completely freeing the mineral from the seam
E21C29/04—Propulsion of machines for slitting or completely freeing the mineral from the seam by cable or chains
E21C29/14—Propulsion of machines for slitting or completely freeing the mineral from the seam by cable or chains by haulage cable or chain pulling the machine along the working face