Double walled tubing and process for producing same
CA 1193838 A · Owner: Apx Group, Inc. · Inventors: Barber, Dennis W.; Kraska, Theodore F.; Trudell, Gerald R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Double walled tubing, a method and apparatus for producing the same are disclosed. First and second metal tubes of substantially identical diameters are selected. One end of the second tube is expanded and the first tube, is pushed into the second tube. By mounting the first tube on a mandrel having a mandrel ball with an outer diameter which approximates the inner diameter of the first tube any, creases in the first tube caused by the insertion will be removed by the mandrel ball upon withdrawing the mandrel from the first tube.
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 September 24, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 24, 2002.
- 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.