THE ARRANGEMENT OF ROCK CUTTING TOOLS ON FULL-FACE TUNNEL BORING MACHINES

In the course of a programme of full and pilot-scale research into rock cutting a method was devised to optimise the layout of cutting tools on the head of a full-face tunnel boring machine. This is achieved by arranging them in such a way that maximum interaction occurs between successive cuts, allowing the full potential of the cutters to be realised, which in turn can either improve excavation rates or, since cutting forces can be reduced, prolong tool life. Estimates of the performance of a multi-tool array on the head of a rock cutting machine are at present obtained by extrapolation of test results on single rock-cutting tools. To apply these results to the field situation, consideration must be given to the constraints of operation that this situation imposes; two major constraints from a rock-cutting point of view are head rotational speed and machine advance rate: other important design considerations are primary debris clearance, machine torque and thrust. Having devised a method for determining tool layout on the cutting head at a particular cutting head speed and advance rate, nomograms have been prepared that relate to the cutting head layout both machine rate of advance and cutting head speed. Consideration in this article is only given to the two most commonly used rock cutting tools, namely drag picks and discs but the method could equally well be applied to most other types of rock cutter. /Author/

  • Corporate Authors:

    Transport and Road Research Laboratory

    Old Wokingham Road
    Crowthorne RG11 6AU, Berkshire,   England 
  • Authors:
    • Hignett, H J
    • O'REILLY, M P
  • Publication Date: 1978

Media Info

  • Features: Figures; References;
  • Pagination: 5 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00178340
  • Record Type: Publication
  • Report/Paper Numbers: TRRL Supp Report 376
  • Files: TRIS, ATRI
  • Created Date: Jul 29 1978 12:00AM