Spiral groove seal arrangement for high vapor-pressure liquids
CA 2046824 C · Owner: Lai, Wei-Tang · Inventors: Pecht, Glenn G.; Lai, Wei-Tang
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A seal system is disclosed for sealing a housing and rotatable shaft against leakage of high vapor-pressure liquids such as natural gas. The method of sealing contemplates phase change of the liquefied hydrocarbon fluid across a first module. The gas so formed is contained by a second seal module which operates as a dry running gas seal. The seal system has plural axially spaced spiral-groove seal modules mounted between the shaft and housing. Each seal module has a primary ring affixed to the housing and a mating ring affixed for rotation with the shaft and the modules define an intermediate cavity. The rings have opposed, radially extending faces one of which has a, plurality of …
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 July 11, 1991 and granted May 14, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 11, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 11, 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.