About Pilot Tube Guided Auger Boring Systems: By using the pilot tube trenchless method of installing underground utilities, water lines and sanitary sewers, you can reduce costs by 50% when compared to complicated laser controlled microtunneling systems.
History 1910-1966 SUNDSTRAND MACHINE TOOL COMPANY© BY FRED R. SWANSON In October 1987, the Rockford Museum Center asked me if I would make a recording, outlining the early history of the Company, and the progress of machine tool design during those 56 Years.
Back — The roof or upper part in any underground mining cavity. Backfill — Mine waste or rock used to support the roof after coal removal. Barren — Said of rock or vein material containing no minerals of value, and of strata without coal, or containing coal in seams too thin to be workable.