Lance for thermally boring rock, concrete, or metal - comprises helically wound ferrous rods

摘要

A thermal lance comprises a tubular metal structure of ferrous metal, the structure comprising a plurality of ferrous rods wound around an axial channel permitting the passage therethrough of a combustible gas. The rods are in contact with each other at adjacent surfaces. The lance can bore deep holes in concrete, rocks and metals without breaking the bored structure. The lance is superior to conventional thin and thick walled tubes.