Patent ID: 8113741
Filing Date: 2012-02-14
Classification: E21B,E21D

Abstract:
1. A boring machine for boring a tunnel from a launch pit to a target pit along a desired boring direction and simultaneously installing a selected one of a plurality of differently-sized product casings in the tunnel, in which each product casing of a selected size has a product casing longitudinal axis, a product casing outside diameter, a product casing inside diameter and a product casing inside surface, wherein the boring machine comprises: (a) an internal casing: (b) an adjustable support assembly that is adapted to be located between the outside surface of the internal casing and the inside surface of the selected product casing for maintaining the coincidence of the internal casing longitudinal axis with the product casing longitudinal axis without closing off the annular space between the internal casing and the selected product casing; (c) an auger which: (d) a rotational mechanism which is operationally connected to the auger; (e) a pusher mechanism which is adapted to advance the selected product casing, the internal casing and the auger; (f) a plurality of cutter heads, each of which: (g) a plurality of front bulkheads, each of which is adapted to be located between the inside surface of a selected one of the product casings and the outside surface of the internal casing behind a cutter head; (h) a plurality of rear bulkheads, each of which: (i) a rear hopper located behind the rear bulkhead; (j) means for directing material cut by the cutter head into the internal casing so that rotation of the auger will convey such material rearwardly within the internal casing to the rear hopper; (k) a transverse conveyor which is: