Drill bit
CA 1202953 A · Owner: Nl Industries, Inc. · Inventors: Fuller, John M.; Barr, John D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
20-, Abstract of the Disclosure, A full bore drag type well drilling bit including a bit body comprised of a generally non-frangible metallic material. The bit body has an operating end face defined by said metallic material to include a plurality of upsets each having a leading edge and at least one recess extending through such leading edge into said metallic material. The end face further includes a plurality of flow paths, each of the leading edges of the upset having one such flow path extending therealong and inset therefrom. At least some of the upsets have a plurality of such recesses spaced therealong. A plurality of circulation ports open through the end face of the bit body the …
Read the whole patent
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 April 8, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 8, 2003.
- 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.