A method having the following steps: running a circulation valve comprising a reactive material into the well bore on the casing; reverse-circulating an activator material in the well bore until the activator material contacts the reactive material of the circulation valve; reconfiguring the circulation...http://www.google.fr/patents/US7503399?utm_source=gb-gplus-shareBrevet US7503399 - Casing shoes and methods of reverse-circulation cementing of casing
Casing shoes and methods of reverse-circulation cementing of casing
