Plugged base pipe for sand control
CA 2106922 A1 · Owner: Restarick, Henry L. · Inventors: Restarick, Henry L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The flow apparatus of a perforated mandrel are temporarily sealed by plugs which are made of a sacrificial material, for example, zinc aluminum and, magnesium. The plugs prevent dirty completion fluid from passing through the screen as it is run into the hole thereby protecting the screen from plugging. While the screen mandrel is temporarily sealed by the plugs cleaning fluid is circulated through a work string and is returned through the annulus between the screen and the well bore for removing filter cake, drilling debris and lost circulation material. After the annulus has been cleaned, it is filled with an acid or caustic solution which dissolves the sacrificial plugs. In an …
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 September 24, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 24, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 24, 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.