Abstract: An underbalanced perforating system is disclosed for use in openhole completions to maximize the wellbore and matrix cleanup efficiency, to connect natural fracture patterns, and/or to enable application of new drilling fluid technology in difficult subsurface environments. The perforating system can be used for any hydrocarbon bearing formations with any lithology.

Abstract: An underbalanced perforating system is disclosed for use in openhole completions to maximize the wellbore and matrix cleanup efficiency, to connect natural fracture patterns, and/or to enable application of new drilling fluid technology in difficult subsurface environments. The perforating system can be used for any hydrocarbon bearing formations with any lithology.

Abstract: A well treatment system of the present invention includes a housing forming a sealed surge chamber, and a surge charge disposed within the sealed surge chamber, wherein the surge charge is adapted upon activation to penetrate the housing and to not penetrate material exterior of the housing. Fluid communication is created between the surge chamber and the wellbore when the housing is penetrated by the surge charge. The penetration permits wellbore fluid to flow quickly into the surge chamber. Fluid flow into the surge chamber may enhance a surge of flow from the formation into the wellbore.

Abstract: A well treatment system of the present invention includes a housing forming a sealed surge chamber, and a surge charge disposed within the sealed surge chamber, wherein the surge charge is adapted upon activation to penetrate the housing and to not penetrate material exterior of the housing. Fluid communication is created between the surge chamber and the wellbore when the housing is penetrated by the surge charge. The penetration permits wellbore fluid to flow quickly into the surge chamber. Fluid flow into the surge chamber may enhance a surge of flow from the formation into the wellbore.

Abstract: A method and apparatus for use in a wellbore includes running a tool string to an interval of the wellbore, and activating a first component in the tool string to create a transient underbalance pressure condition in the wellbore interval. Additionally, a second component in the tool string is activated to create a transient overbalance pressure condition in the wellbore interval, or vice versa.

Abstract: A well treatment system of the present invention includes a housing forming a sealed surge chamber, and a surge charge disposed within the sealed surge chamber, wherein the surge charge is adapted upon activation to penetrate the housing and to not penetrate material exterior of the housing. Fluid communication is created between the surge chamber and the wellbore when the housing is penetrated by the surge charge. The penetration permits wellbore fluid to flow quickly into the surge chamber. Fluid flow into the surge chamber may enhance a surge of flow from the formation into the wellbore.

Abstract: A method and apparatus for improving reservoir communication includes, in one arrangement, causing creation of tunnels in surrounding formation of a well interval, and applying treatment fluid to the tunnels. A local transient underbalance condition is created in the well interval after creation of the tunnels in the formation and application of the treatment fluids.

Abstract: A method and apparatus for use in a wellbore includes running a tool string to an interval of the wellbore, and activating a first component in the tool string to create a transient underbalance pressure condition in the wellbore interval. Additionally, a second component in the tool string is activated to create a transient overbalance pressure condition in the wellbore interval, or vice versa.

Abstract: A shaped charge includes a charge case; an explosive disposed inside the charge case; and a liner for retaining the explosive in the charge case, wherein the liner comprises a material reactive with a component of an earth formation. A method for perforating in a well includes disposing a perforating gun in the well, wherein the perforating gun comprises a shaped charge having a charge case, an explosive disposed inside the charge case, and a liner for retaining the explosive in the charge case, wherein the liner includes a material that can react with a component of an earth formation; detonating the shaped charge to form a perforation tunnel in a formation zone; and allowing the material comprising the liner to react with the component of the earth formation.

Abstract: An apparatus for reducing the post-detonation pressure of a perforating gun, the apparatus including a perforating gun carrying at least one explosive charge, wherein when the explosive charge is detonated the explosive charge produces a pressurized detonation gas, and a mechanism for reducing the pressure of the detonation gas proximate the perforating gun. The detonation gas pressure is desirably reduced in a time frame sufficient to create a dynamic underbalance condition to facilitate a surge flow of fluid from a reservoir into a wellbore. The pressure reduction mechanism may include singularly or in combination a heat sink to reduce the temperature of the detonation gas, a reactant to recombine with the reactant gas and reduce the molar density of the detonation gas, and a physical compression mechanism to utilize the waste energy of the detonation gas to create work, simultaneously reducing the temperature of the gas and the molar density of the detonation gas.

Abstract: An apparatus and method includes positioning a string in a wellbore, the string having a surge chamber. A closure member is provided below the well surface, with the surge chamber defined at least in part by the closure member. At least one port to the chamber is opened to create a fluid surge into the surge chamber and a local low pressure condition in a wellbore region.

Abstract: An apparatus for reducing the post-detonation pressure of a perforating gun, the apparatus including a perforating gun carrying at least one explosive charge, wherein when the explosive charge is detonated the explosive charge produces a pressurized detonation gas, and a mechanism for reducing the pressure of the detonation gas proximate the perforating gun. The detonation gas pressure is desirably reduced in a time frame sufficient to create a dynamic underbalance condition to facilitate a surge flow of fluid from a reservoir into a wellbore. The pressure reduction mechanism may include singularly or in combination a heat sink to reduce the temperature of the detonation gas, a reactant to recombine with the reactant gas and reduce the molar density of the detonation gas, and a physical compression mechanism to utilize the waste energy of the detonation gas to create work, simultaneously reducing the temperature of the gas and the molar density of the detonation gas.

Abstract: An underbalanced perforating system is disclosed for use in openhole completions to maximize the wellbore and matrix cleanup efficiency, to connect natural fracture patterns, and/or to enable application of new drilling fluid technology in difficult subsurface environments. The perforating system can be used for any hydrocarbon bearing formations with any lithology.

Abstract: An apparatus and method is provided to reduce interference resulting from activation of explosive devices. To reduce interference, one or more shock impeding elements are placed proximal one or more explosives to impede propagation of shock caused by detonation of the explosives. The shock impeding elements include a porous material, such as a porous liquid or solid.

Abstract: An apparatus and method of perforating and surging a section of the wellbore includes running a perforating gun into the well on a string having an isolation valve above the perforating gun, closing the valve, and perforating the well with the isolation valve closed so that the formation is isolated from the well surface. An underbalance pressure is provided above the isolation valve, and then, the isolation valve is opened to surge the formation.

Abstract: A well treatment system of the present invention includes a housing forming a sealed surge chamber, and a surge charge disposed within the sealed surge chamber, wherein the surge charge is adapted upon activation to penetrate the housing and to not penetrate material exterior of the housing. Fluid communication is created between the surge chamber and the wellbore when the housing is penetrated by the surge charge. The penetration permits wellbore fluid to flow quickly into the surge chamber. Fluid flow into the surge chamber may enhance a surge of flow from the formation into the wellbore.

Abstract: A method and apparatus for use in a wellbore includes running a tool string to an interval of the wellbore, and activating a first component in the tool string to create a transient underbalance pressure condition in the wellbore interval. Additionally, a second component in the tool string is activated to create a transient overbalance pressure condition in the wellbore interval, or vice versa.

Abstract: An apparatus and method of perforating and surging a section of the wellbore includes running a perforating gun into the well on a string having an isolation valve above the perforating gun, closing the valve, and perforating the well with the isolation valve closed so that the formation is isolated from the well surface. An underbalance pressure is provided above the isolation valve, and then, the isolation valve is opened to surge the formation.

Abstract: An apparatus and method includes positioning a string in a wellbore, the string having a surge chamber. A closure member is provided below the well surface, with the surge chamber defined at least in part by the closure member. At least one port to the chamber is opened to create a fluid surge into the surge chamber and a local low pressure condition in a wellbore region.

Abstract: A method and apparatus for improving reservoir communication includes, in one arrangement, causing creation of tunnels in surrounding formation of a well interval, and applying treatment fluid to the tunnels. A local transient underbalance condition is created in the well interval after creation of the tunnels in the formation and application of the treatment fluids.