Apparatus and method for making and breaking joints in drill pipe strings
CA 2092409 C · Owner: Hawk Industries, Inc. · Inventors: Hauk, Thomas D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A power apparatus and method for making and breaking joints in drill pipe strings in oil wells in which a single, torquing cylinder (24) that always moves in a single direction while torquing, both makes and breaks the joints. Three levels (21, 22, 23) of jaw elements (52 52a) are employed, the, top and bottom jaw levels (21 23) being identical to each, other, all jaw elements being interconnected as by a frame (10). Other cylinders (52, 52a) close the jaws (36 37) at each, level. The apparatus is moved vertically; two levels of jaw elements are employed for making and another combination of two levels is employed for breaking. Special die and cam means (66) are provided to grip the drill …
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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
- Filed August 28, 1991 and granted November 18, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 28, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 28, 2013.
- 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.