Apparatus and method for forming an anlarged underground arcuate bore and installing a conduit therein
CA 1258262 A · Owner: Cherrington, Martin D. · Inventors: Cherrington, William D.; Cherrington, Martin D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus and method for drilling a pilot bore hole (B) along an underground arcuate path (P) between two surface locations (O, E). The pilot bore hole (B) is drilled in one direction with a drill string (10) having a leading pipe section (10A) of a reduced diameter to provide increased flexibility. Upon completion of the pilot bore hole (B), a reamer (48) connected to a product conduit (46) is connected to the drill string (10). Drill string (10) pulls the reamer (48) and product conduit (46) along the pilot bore hole (B) in an opposite direction for enlarging the bore hole (B) to receive the product conduit (46). A spud bit 34) has a flat or blunt leading end portion (34A) with a …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted August 8, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 8, 2006.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.