Plug-dropping container for releasing a plug into a wellbore

The plug-dropping container of 21, wherein:

• the flapper valve comprises a solid curved flapper to serve as the solid surface, and a seat to serve as the channel;
• the canister comprises a lower bypass port positioned below the flapper valve;
• and
• the flapper valve further comprises a shaft for rotating the flapper from (1) an object-retained position such that the flapper blocks the downward release of the object from the canister to an object-released position but permits fluid to flow from the annulus, around the flapper, and through the lower bypass port, to (2) an object-released position such that the flapper substantially seals the lower bypass port and the seat receives the object.

A plug-dropping container for dispensing plugs into a wellbore during a cementing operation, the plug-dropping container being connected to a cementing head having a fluid flow channel therein for receiving fluids, the plug-dropping container, comprising:

• a tubular housing having a top opening and a bottom opening, the housing being in fluid communication with the bore in the cementing head;
• an upper canister disposed within and generally aligned with the housing so as to define an upper annulus between the tubular housing and the upper canister, the upper canister also having a top opening and a bottom opening;
• a channel within the upper canister, the channel of the upper canister being configured to receive a top plug therein;
• an upper bypass proximate to the top opening of the upper canister for permitting fluid to flow into the upper annulus;
• an upper plug-retaining valve disposed within the housing proximal to the bottom opening of the upper canister, the upper plug-retaining valve having a solid surface, and having a channel through the valve;
• a lower canister disposed within and generally aligned with the housing and below the upper plug-retaining valve so as to define a lower annulus between the housing and the lower canister, the lower canister also having a top opening and a bottom opening;
• a channel within the lower canister, the channel of the lower canister being configured to receive a bottom plug therein;
• a lower bypass proximate to the top opening of the lower canister for permitting fluid to flow into the lower annulus;
• a lower plug-retaining valve disposed within the housing below the bottom opening of the lower canister, the lower plug-retaining valve having a solid surface, and having a channel through the valve;
• wherein the lower plug-retaining valve is movable from a plug-retained position to a plug-released position such that (1) in its plug-retained position, the solid surface of the lower valve substantially blocks the plug from exiting the lower canister, but fluids are permitted to flow around the lower valve, and (2) in its plug-released position, the channel of the lower valve is in substantial alignment with the channel of the lower canister thereby permitting the plug to exit the lower canister and to travel downward through the channel of the lower valve, and the solid surface of the valve substantially blocks the flow of fluid around the valve;
• and
• wherein the upper plug-retaining valve is movable from a plug-retained position to a plug-released position such that (1) in its plug-retained position, the solid surface of the upper valve substantially blocks the plug bottom from exiting the lower canister, but fluids are permitted to flow around the lower valve, and (2) in its plug-released position, the channel of the upper valve is in substantial alignment with the channel of the upper canister thereby permitting the plug to exit the upper canister and to travel downward through the channel of the upper valve, and the solid surface of the valve substantially blocks the flow of fluid around the valve.

The plug-dropping container of 38, wherein:

• the flapper valve comprises a solid curved flapper to serve as the solid surface, and a seat to serve as the channel;
• the canister comprises a lower bypass port positioned below the flapper valve;
• and
• the flapper valve further comprises a shaft for rotating the flapper from (1) an object-retained position such that the flapper blocks the downward release of the object from the canister to an object-released position but permits fluid to flow from the annulus, around the flapper, and through the lower bypass port, to (2) an object-released position such that the flapper substantially seals the lower bypass port and the seat receives the plug.

A plug-dropping container within a head member for releasing an object into a wellbore, the plug-dropping container comprising:

• a tubular housing;
• a tubular canister disposed within and generally aligned with the tubular housing so as to define an annulus between the tubular housing and the canister, the canister having an inner surface;
• a channel along the inner surface of the canister, the canister channel being configured to receive the object therein;
• a valve disposed within the tubular housing proximal to the lower end of canister, the valve having a solid radial surface, and having a channel through the valve;
• wherein the valve is rotatable from an object-retained position to an object-released position such that (1) in its object-retained position, the radial surface of the valve substantially blocks the object from exiting the canister, and (2) in its object-released position, the channel of the valve is in substantial alignment with the channel of the canister thereby permitting the object to exit the canister and to travel downward through the channel of the valve, and wherein the radial surface around a perimeter of one end of the valve channel is placed in close proximity with the lower channel of the head member where it substantially blocks the flow in the annulus between the tubular housing and the canister in the object-released position.

A plug-dropping container within a head member for releasing an object into a wellbore, the plug-dropping container comprising:

• a tubular housing;
• a tubular canister disposed within and generally aligned with the tubular housing so as to define an annulus between the tubular housing and the canister, the canister having an inner surface;
• a channel along the inner surface of the canister, the canister channel being configured to receive the object therein;
• a valve disposed within the tubular housing proximal to the lower end of canister, the valve defining a plate comprising a solid surface and a channel offset from the solid surface;
• wherein the valve is movable from an object-retained position to an object-released position such that (1) in its object-retained position, the solid surface of the valve blocks the object from exiting the canister, and (2) in its object-released position, the channel of the valve is in substantial alignment with the channel of the canister thereby permitting the object to exit the canister and to travel downward through the channel of the valve.

A plug-dropping container within a head member for releasing an object into a wellbore, the plug-dropping container comprising:

• a tubular housing;
• a tubular canister disposed within and generally aligned with the tubular housing so as to define an annulus between the tubular housing and the canister, the canister having an inner surface and a lower bypass port;
• a channel along the inner surface of the canister, the canister channel being configured to receive the object therein;
• a flapper valve disposed within the tubular housing proximal to the lower end of the canister but above the lower bypass port, the flapper valve comprising a solid curved flapper, a shaft for rotating the flapper, and a seat to serve as the channel;
• wherein the shaft is rotatable to move the flapper valve from an object-retained position to an object-released position such that (1) in its object-retained position, the curved flapper of the valve substantially blocks the object from exiting the canister, but fluids are permitted to flow around the flapper and through the lower bypass port, and (2) in its object-released position, the flapper moves to permit the object to exit the canister and to travel downward through the seat, and substantially seals the lower bypass port.