Ball drop tool and methods of use

Abstract

Disclosed embodiments include a method and apparatus for dropping a ball in a tool string. One example embodiment is a downhole ball drop tool that releases an activation ball in response to a downlink signal provided from the surface. The ball drop tool is provided as a part of a tool string. A variety of tools connected in a tool string may have a ball seat for receiving an activation ball dropped from the ball drop tool. Once the ball has engaged the ball seat, fluid pressure can be increased in the tool string to activate a mechanism in a downhole tool.

What is claimed is: 
     
         1 . An apparatus comprising:
 a housing adapted to be connected within a tool string, wherein the housing includes a central bore defining a flow path through the housing;   a mandrel located in the housing for retaining at least one drop ball;   a downlink receiver; and   a deployment mechanism configured to retain at least one drop ball in the mandrel, the deployment mechanism in operable communication with the downlink receiver, the deployment mechanism actuable in response to a signal from the downlink receiver to release a retained drop ball from the mandrel into the central bore.   
     
     
         2 . The apparatus of  claim 1 , wherein the mandrel is positioned to be radially offset from the central bore. 
     
     
         3 . The apparatus of  claim 1 , further comprising a second ball releasably retained within the mandrel. 
     
     
         4 . The apparatus of  claim 3 , wherein the first ball is an activation ball and the second ball is a de-activation ball. 
     
     
         5 . The apparatus of  claim 1 , wherein the electromechanical deployment mechanism comprises a solenoid-driven actuator. 
     
     
         6 . The apparatus of  claim 1 , wherein the downlink receiver comprises a pressure sensor. 
     
     
         7 . The apparatus of  claim 1 , wherein the signal from the downlink receiver causes the electromechanical deployment mechanism to actuate between a retaining position and a releasing position. 
     
     
         8 . The apparatus of  claim 1 , wherein the housing is threaded at an upper end and a lower end to be connected within the drill string. 
     
     
         9 . The apparatus of  claim 1 , further comprising a radial bore connecting the mandrel and the central bore of the housing. 
     
     
         10 . The apparatus of  claim 1 , wherein the signal from the downlink receiver is generated in response to a flow of fluid along the flow path through the housing. 
     
     
         11 . The apparatus of  claim 1 , wherein the housing is connected in the drill string above a reamer. 
     
     
         12 . A method of dropping a ball to engage a ball seat located in a downhole tool, the method comprising:
 providing a ball drop tool along a tool string, wherein the ball drop tool is positioned uphole of the downhole tool;   retaining a first ball within a mandrel of the ball drop tool;   receiving a downlink signal at a downlink receiver;   actuating, in response to the received signal, an electromechanical deployment mechanism to release the first ball from the mandrel; and   releasing the first ball from the mandrel.   
     
     
         13 . The method of  claim 12 , wherein the step of receiving the downlink signal comprises detecting a series of pulses transmitted along the tool string using mud pulse telemetry. 
     
     
         14 . The method of  claim 12 , wherein the downlink signal is generated at a surface transmitter and transmitted downhole using mud pulse telemetry. 
     
     
         15 . The method of  claim 12 , wherein the step of actuating the electromechanical deployment mechanism comprises actuating a solenoid-driven actuator between a retaining position and a releasing position. 
     
     
         16 . The method of  claim 12 , further comprising:
 engaging the ball seat in the downhole tool with the first ball; and   activating a mechanism of the downhole tool.   
     
     
         17 . The method of  claim 16 , wherein the step of activating the mechanism comprises hydraulically activating a reamer. 
     
     
         18 . The method of  claim 12 , further comprising:
 retaining a second ball within the mandrel of the ball drop tool; and   releasing the second ball from the mandrel in response to a deactivation signal received at the downlink receiver.   
     
     
         19 . The method of  claim 12 , further comprising the step of displacing drilling fluid into the tool string to displace the released first ball in a downhole direction towards the ball seat. 
     
     
         20 . A downhole ball dropping system, the system comprising:
 a ball drop tool connected within a drill string, wherein the ball drop tool is communicably coupled to a downlink receiver, the ball drop tool having a mandrel configured to retain a drop ball; and   an electromechanical deployment mechanism configured to be actuated in response to a signal from the downlink receiver to release the drop ball from the mandrel.