Stage tool for wellbore cementing
A stage tool for wellbore annular cementing may be opened for cementing by hydraulic actuation of a sliding sleeve valve from over a fluid port. After sufficient cement has been introduced, the stage tool fluid port can be closed by compressing two telescopically arranged parts of its tubular body to further overlap each other and overlie the fluid port. This permits the stage tool to be closed without employing a plug.
1. A stage tool for cementing a wellbore annulus comprising:
a first tubular and a portless second tubular, wherein a longitudinal bore extends through the first tubular and the second tubular;
a fluid port through the first tubular to provide fluidic access between the longitudinal bore and the annulus; and
a backup sleeve axially movable in the stage tool adapted to selectively open and close the fluid port against fluid flow therethrough;
wherein the first tubular is axially slidable with respect to the second tubular to close the fluid port upon application of a compressive force.
2. The stage tool of claim 1 further comprising a key in the first tubular and a slot in the second tubular to guide the axial movement of the first tubular.
3. The stage tool of claim 1 further comprising locks to hold the first tubular with the second tubular in a compressed position, to keep the fluid port closed.
4. The stage tool of claim 1 further comprising slips to hold the second tubular in a place inside the wellbore.
5. The stage tool of claim 3 , wherein the lock is a ratchet collet lock.
6. A method of cementing a well bore annulus using a stage tool including a first tubular, a portless second tubular, a fluid port on the first tubular, and a longitudinal bore through the first tubular and the second tubular, the method comprising:
running the stage tool into a well bore towards a selected position in the wellbore;
applying hydraulic pressure in the longitudinal bore to shift a backup sleeve to open the fluid port;
pumping the cement through the fluid port into the well bore annulus; and
applying a compressive force on the first tubular to axially slide the first tubular towards the second tubular to close the fluid port.
7. The method of claim 6 further comprising guiding the first tubular in the second tubular by a key in the first tubular and a slot in the second tubular.
8. The method of claim 6 further comprising holding the second tubular at the compressed position inside the well bore during the application of compressive force.
9. The method of claim 6 further comprising locking the first tubular and the second tubular to a position upon the closure of the fluid port.
10. The method of claim 6 further comprising moving the backup sleeve to additionally close the fluid port.