Process for manufacturing seamless metal tubes
CA 1159686 A · Owner: Sumitomo Kinzoku Kogyo Kabushiki Gaisha · Inventors: Yamada, Tateo; Hayashi, Chihiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to the manufacture of seamless metal tubes by a cross- roll helical rolling process such as Mannesmann mandrel mill process or by a press piercing process such as Ugine Sejournet process. Shells being worked are subjected to outside-diameter reduction by means of a rotary mill having 3 or 4 rolls without using internal sizing tools such as plug and mandrel bar, so that wall eccentricity is significantly improoved, which fact assured higher quality of finished product. The process of the invention permits decreasing the number of sizes or billets as materials for tube making. -39-
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 January 3, 1984. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 3, 2001.
- 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.