INTRODUCTORY NOTES ON NUMERICAL CONTROL LOFTING

During the past fifteen years or so, the practice of ship lofting has undergone a marked shift in procedure from that of the manual exercise of producing full sized dimensions and outlines on the lofting floor to the extensive use of machine aids, which considerably expedite the procedure. To the shipbuilding industry this means that loftsmen schooled in the use of computer technology can now increase productivity. This change in procedure is world-wide, and it is gradually being implemented throughout U. S. production yards. This developing technology is commonly referred to as Numerical Control Lofting, or more simply as N/C Lofting. As with its manual predecessor, the role of N/C Lofting is to span the gap between the final production drawings and the actual fitting up of the structural elements at the sub-assembly site. The fundamental distinguishing feature of N/C Lofting is that all information is stored in a numerical format rather than on scrieving boards and the like. Once established this information may then be retrieved and augmented at will to reproduce the molded hull geometry in the form of drawings or visual displays, as well as producing shell expansions, tables of offsets, intersections, seams, etc. This augmented information may be coupled with an algorithmic geometry to code instructions for the numerical control of plate burning equipment, thus simplifying the production of individual construction members. The purpose of this paper is to provide the general reader familiar with the production aspects of shipbuilding with an overview of the activities associated with this technology. The authors hope to present a sufficiently comprehensive picture of the procedure to reveal the interface between the various functions performed, while at the same time keeping the discussions general enough to avoid the specifics of any one lofting system.

  • Supplemental Notes:
    • Paper presented February 1980 to the Texas Section, SNAME.
  • Corporate Authors:

    Society of Naval Architects and Marine Engineers

    601 Pavonia Avenue
    Jersey City, NJ  United States  07306-2907
  • Authors:
    • Phillips, E F
    • Kupersmith, J A
  • Publication Date: 1980

Media Info

  • Features: References;
  • Pagination: 29 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00316615
  • Record Type: Publication
  • Report/Paper Numbers: Conf Paper
  • Files: TRIS
  • Created Date: Sep 16 1980 12:00AM