Ball injecting apparatus for wellbore operations

Abstract

Apparatus is provided injecting drop balls into a wellbore, such as for actuating downhole tools. A ball magazine adapted for storing drop balls, in two or more transverse ball chambers, is axially movable in a magazine housing mounted at a transverse port to a fluid passage in fluid communication with the wellbore. The magazine is serially actuable for aligning a first and subsequent chambers with the transverse port for injecting stored balls to the wellbore. An indicator, such as a rod extending from the magazine housing, can be used to indicate the relative location of the chamber and transverse port. The apparatus can be used in a system and methodology for actuating two or more downhole tools spaced at intervals along the wellbore.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a regular application claiming priority of U.S. Provisional Patent application Ser. No. 60 / 895,350, filed on Mar. 16, 2007, the entirety of which is incorporated herein by reference.FIELD OF THE INVENTION[0002]This invention relates generally to apparatus and method for injecting balls into a wellbore, such as drop balls, frac balls, packer balls and other balls for interacting with downhole tools or for blocking perforations in casing in the wellbore. More particularly, the apparatus and method uses an actuator and ball magazine for controllably releasing balls into a fluid stream which is pumped into the wellbore.BACKGROUND OF THE INVENTION[0003]It is known to conduct fracturing or other stimulation procedures in a wellbore by isolating zones in the wellbore using packers and the like and subjecting the isolated zone to treatment fluids at treatment pressures. In a typical fracturing procedure, for example, the casin...

AI Technical Summary

Problems solved by technology

The treatment fluid is energized which is highly dangerous.

Aside from being a generally dangerous practice, other operational problems have occurred, such as valves malfunctioning and balls becoming stuck and not being pumped downhole.

These problems have resulted in failed well treatment operations, requiring re-working which is very costly and inefficient.

At times re-working of a well formation following an unsuccessful stimulation treatment may not be successful, which results in production loss.

The multi-port arrangement, although workable, has proven to be very costly and inefficient.

Further, this arrangement is dangerous to personnel due to the multiplicity of lines under high pressure connected to the top the wellhead during the stimulation operation.

The apparatus appears limited to same-sized balls and there is not positive identification whether a ball was successfully indexed from the stack for injection.

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