Positive circulating valve with retrievable standing valve

A downhole tool comprising:

• a circulating valve adapted for connection to a tool string and having an open position and a closed position, said circulating valve comprising:
• a standing valve for preventing downward flow of fluid when said circulating valve is in said open position, and allowing upward fluid flow through said circulating valve, wherein downward fluid flow is allowed through said circulating valve and around said standing valve when said circulating valve is in said closed position;
• and
• a packer disposed below said circulating valve, wherein setting of said packer results in movement of said circulating valve from said open position to said closed position.

A circulating valve for use in a wellbore, said circulating valve comprising:

• mandrel means for connecting to a tool string, said mandrel means defining a mandrel central opening therethrough and a mandrel port in communication with said mandrel central opening;
• housing means for slidably receiving at least a portion of said mandrel means therein, said housing means defining a housing port therein, and said housing means defining a housing central opening therethrough;
• sealing means for sealing between said mandrel means and said housing means, wherein said mandrel means is movable between an open position in which said mandrel port is on one side of said sealing means and in communication with said housing port and a closed position in which said mandrel port is on an opposite side of said sealing means, and said mandrel port is in communication with at least a portion of said housing central opening when said mandrel means is in said closed position;
• and
• a standing valve disposed in said mandrel central opening of said mandrel means for substantially preventing fluid flow downwardly through said mandrel means and for allowing fluid flow upwardly through said mandrel means.

A circulating valve for use in a wellbore, said circulating valve comprising:

• mandrel means for connecting to a tool string, said mandrel means defining a mandrel central opening therethrough and a mandrel port in communication with said mandrel central opening;
• housing means for slidably receiving at least a portion of said mandrel means therein, said housing means defining a housing port therein;
• sealing means for sealing between said mandrel means and said housing means, wherein said mandrel means is movable between an open position in which said mandrel port is on one side of said sealing means and in communication with said housing port and a closed position in which said mandrel port is on an opposite side of said sealing means;
• J-slot means for controlling movement of said mandrel means with respect to said housing means between said open and closed positions;
• and
• a standing valve disposed in said mandrel central opening of said mandrel means for substantially preventing fluid flow downwardly through said mandrel means and for allowing fluid flow upwardly through said mandrel means.