Well completion apparatus and methods

Abstract

A wellbore tool includes a perforating charge adapted to create a tunnel in a subterranean formation upon activation; a propellant that provides a pressure cycle when activated; and a delay device operationally connected to the perforating charge and the propellant to activate the perforating charge and the propellant in a manner to influence a selected wellbore condition.

1 . A wellbore tool comprising:
 a perforating charge adapted to create a tunnel in a subterranean formation upon activation;   a propellant that provides a pressure cycle when activated;   a first delay device operationally connected to the perforating charge to activate the perforating charge; and   a second delay device operationally connected to the propellant to activate the propellant in a manner to influence a selected wellbore condition.   
     
     
         2 . The tool of  claim 1 , wherein the propellant comprises a solid propellant material. 
     
     
         3 . The tool of  claim 1 , wherein the wellbore condition is an underbalance condition occurring proximate to the completion of a tunnel formed in a subterranean formation by activation of the perforating charge. 
     
     
         4 . The tool of  claim 1 , wherein the wellbore condition is a pressure differential between a wellbore pressure and a formation pressure. 
     
     
         5 . The tool of  claim 4 , wherein the wellbore condition is an underbalance condition occurring proximate to the completion of a tunnel formed in a subterranean formation by activation of the perforating charge. 
     
     
         6 . The tool of  claim 4 , wherein the wellbore condition is an overbalance condition occurring proximate to the completion of a tunnel formed in a subterranean formation by activation of the perforating charge. 
     
     
         7 . The tool of  claim 1 , wherein the wellbore condition is selected from a group of underbalance, overbalance, or balanced. 
     
     
         8 . The tool of  claim 3 , wherein the propellant comprises a solid propellant material. 
     
     
         9 . The tool of  claim 5 , wherein the propellant comprises a solid propellant material. 
     
     
         10 . A method of influencing a wellbore pressure cycle during a wellbore operation, the method comprising the steps of:
 performing a wellbore operation;   activating a propellant in the wellbore; and   influencing a selected wellbore condition.   
     
     
         11 . The method of  claim 10 , wherein the wellbore operation is a perforating operation. 
     
     
         12 . The method of  claim 10 , wherein the propellant comprises a solid propellant material. 
     
     
         13 . The method of  claim 10 , where the propellant temporarily provides a pressure cycle. 
     
     
         14 . The method of  claim 10 , wherein the step of influencing includes the step of correlating a pressure cycle provided by the activated propellant with the wellbore operation. 
     
     
         15 . A method for performing a wellbore perforating operation comprising the steps of:
 detonating a perforating gun in a wellbore to create a tunnel in a target formation;   activating a propellant; and   influencing a selected wellbore condition.   
     
     
         16 . The method of  claim 15 , wherein the step of influencing comprises timing the step of activating and the step of detonating relative to one another. 
     
     
         17 . The method of  claim 15 , wherein the step of activating the propellant is timed relative to the step of detonating the perforating gun to influence a wellbore condition proximate a time of completion of the tunnel. 
     
     
         18 . The method of  claim 1   5 , wherein the wellbore condition is one of underbalance, balanced, or overbalanced 
     
     
         19 . The method of  claim 15 , wherein the step of activating the propellant is performed prior to detonation of the perforating gun to influence an underbalance condition proximate completion of the tunnel. 
     
     
         20 . The method of  claim 15 , wherein the propellant is a solid propellant material providing a known pressure cycle.