Magnetic flaw detector for tubular goods
CA 2113345 C · Owner: Western Atlas International, Inc. · Inventors: Hwang, Jackson H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A magnetic flaw detector for use in small-diameter tubular goods employs a second magnetic field (30) to confine a first magnetic field (10) to reside within a desired volumetric region in the wall of a specimen under test. A flux leakage detector (36) and a variable reluctance sensor (38) provide means for detecting and discriminating between defects on the inner and outer surfaces of the specimen (10).
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
- Filed May 12, 1993 and granted May 20, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 12, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 12, 2015.
- 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.