Washpipeless isolation strings and methods for isolation

An isolation string for multiple zone isolations, said string comprising:

• a lower isolation section and an upper isolation section,
• said lower isolation section comprising:
• a lower section upper packer, and
• a lower section isolation pipe in mechanical communication with the lower section upper packer, wherein said lower section isolation pipe comprises a pressure activated valve and a lower section object activated valve,
• said upper isolation section comprising:
• an upper section upper packer;
• a double-sub valve comprising first and second concentric subs, wherein said double-sub valve is in mechanical communication with the upper section upper packer;
• an upper section isolation pipe in mechanical communication with the first sub of said double-sub valve, wherein said isolation pipe comprises an upper section object activated valve;
• and
• a production pipe in mechanical communication with the second sub of said double-sub valve,
• wherein the upper section isolation pipe and the production pipe sting into the lower section upper packer.

An isolation string for multiple zone isolations, said string comprising:

• a lower isolation section and an upper isolation section,
• said lower isolation section comprising:
• a lower section upper packer;
• a lower section double-sub valve comprising first and second concentric subs, wherein said lower section double-sub valve is in mechanical communication with the lower section upper packer;
• an lower section isolation pipe in mechanical communication with the first sub of said double-sub valve, wherein said lower section isolation pipe comprises an lower section object activated valve;
• and
• a lower section production pipe in mechanical communication with the second sub of said double-sub valve,
• said upper isolation section comprising:
• an upper section upper packer;
• a double-sub valve comprising first and second concentric subs, wherein said double-sub valve is in mechanical communication with the upper section upper packer;
• an upper section isolation pipe in mechanical communication with the first sub of said double-sub valve, wherein said isolation pipe comprises an upper section object activated valve;
• and
• a production pipe in mechanical communication with the second sub of said double-sub valve,
• wherein the upper section isolation pipe and the production pipe sting into the lower section upper packer.

An isolation system for a production zone in a well comprising:

• a first packer adjacent one end of the production zone;
• a second packer adjacent another end of the production zone;
• and
• a conduit coupled between the first and second packers and comprising a pressure activated valve and an object activated valve, and a production screen, such that each of the packers and conduit are unassociated with a removable service tool, and a fluid from between the two packers and the exterior of the production screen is communicable with the pressure activated valve and the object activated valve.

A method for isolating a production zone of a well, comprising:

• running in the well on a service tool, an isolation string comprising a first packer, a pressure activated valve, an object activated valve, and a production screen and wherein the object activated valve is not associated with the service tool;
• setting the first packer of the isolation string in the well adjacent perforations in the well;
• releasing an object from the service tool;
• contacting the object activated valve with the released object to activate the object activated valve to a closed condition;
• and
• withdrawing the service tool from the isolated production zone.