The manufacturers, Atlas, claim that hydraulic rock drills cut 50 percent faster than pneumatically driven drills, they are much quieter, cheaper to run and have a longer bit life. Filtering the hydraulic oil down to three microns ensures that the rig will run for more than 4000 hours without a major overhaul; some engineers however claim that the pneumatic drill is much less sensitive, taking impurities up to 15 microns without any ill effect. An added advantage of the pneumatic system is that it will blow out impurities the sealed hydraulic unit will not. Economical running costs claimed for the new drill arise from the more efficient use of power and less transmission loss. Drill life is increased by feeding flushing water in to the drill steel through a tube. The rig is powered by electricity which is taken into the units at 6kv and stepped down by a transformer near the work face. The basic unit consisting of a 45kw power pack, drill and boom can be assembled to give up to six drills in a variety of designs. The performance of the first Atlas hydraulic drill in the Furka Tunnel through the Swiss Alps is described. The contractor has had some initial difficulties in getting men skilled in the new techniques. /TRRL/

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 26-27
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00129984
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Apr 7 1976 12:00AM