Abstract: A method and apparatus for controlling a transient underbalance condition is provided. Transient underbalance can be enhanced by using a porous material, such as a porous solid, around the explosive device. The porous material contains a volume to receive wellbore fluids in response to activation of the explosive device. This causes a local drop in pressure, which enhances the transient underbalance effect. In another application, it is desired to reduce the transient underbalance effect. This is accomplished by reducing the pressure drop generated as a result of explosive detonation. In one arrangement, the shot density is reduced by using solid masses.

Abstract: A booster to relay a detonation train from a detonating cord to another booster includes an explosive and a shell. The shell has an open end to receive an end of the detonating cord and an indented closed end that is adapted to form a projectile to strike the other booster when the explosive detonates. The explosive may include at least fifty percent by weight of NONA, and in some embodiments, the explosive may be primarily NONA.

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: A method and apparatus for improving reservoir communication includes, in one arrangement, use of one or more chambers to create an underbalance condition and/or a fluid surge in the wellbore. In another arrangement, a tool string comprises a packer, a circulating valve, and an atmospheric chamber, in which the circulating valve, when open, is adapted to vent a lower wellbore region below the packer when the packer is set, and the atmospheric chamber is capable of being operated to create an underbalance condition below the packer. In yet another arrangement, an apparatus comprises a subsea wellhead equipment including a blow-out preventer, choke line filled with a low density fluid, and a kill line filled with a heavy fluid. The choke line is adapted to be opened to create an underbalance condition in the wellbore.

Abstract: A method and apparatus for controlling a transient underbalance condition is provided. Transient underbalance can be enhanced by using a porous material, such as a porous solid, around the explosive device. The porous material contains a volume to receive wellbore fluids in response to activation of the explosive device. This causes a local drop in pressure, which enhances the transient underbalance effect. In another application, it is desired to reduce the transient underbalance effect. This is accomplished by reducing the pressure drop generated as a result of explosive detonation. In one arrangement, the shot density is reduced by using solid masses.

Abstract: An apparatus and method is provided to reduce interference resulting from activation of explosive devices. One type of interference is charge-to-charge interference, and another type of interference is pre-shock interference between a detonating cord and an explosive, such as a shaped charge. 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. In another arrangement, a shock barrier may be positioned between a detonating cord and an explosive to reduce pre-shock interference. In yet another feature, an encapsulant may be provided around one or more shaped charges to enhance structural support for the shaped charges.

Abstract: An apparatus and method is provided to provide structural support for explosives (e.g., shaped charges) in a tool (e.g., a perforating gun). An encapsulant surrounds at least portions of the explosives to provide structural support for the explosives. The encapsulant contains a porous material, such as porous cement or polymer.

Abstract: The present invention provides a debris free perforating system. In one embodiment, the debris free perforating system includes a caseless shaped charge carried by a solid loading tube, such as Styrofoam™ or paper. The loading tube can additionally be combustible and can be coated with an oxidizer to ensure incineration.

Abstract: A booster to relay a detonation train from a detonating cord to another booster includes an explosive and a shell. The shell has an open end to receive an end of the detonating cord and an indented closed end that is adapted to form a projectile to strike the other booster when the explosive detonates. The explosive may include at least fifty percent by weight of NONA, and in some embodiments, the explosive may be primarily NONA.

Abstract: The present invention provides explosive compositions adapted for use in downhole well applications requiring high temperature explosives that may be exposed to elevated temperatures for extended periods of time.

Abstract: A process for forming granules (e.g., alpha-HMX containing granules) from at least one particulate material comprises the steps of: (a) selecting particulates (e.g., alpha-HMX particulates) having a particle size distribution; and (b) fluidizing the particulates, whereby particulates agglomerate to form granules. Optionally, the particulates can be coated with one or more second materials, such as energetic materials or fuels. If one or more of the second materials comprise polymerizable monomers, the process can optionally further comprise the step of polymerizing those monomers in situ, either before or after the granule is formed.

Abstract: A method includes arranging shaped charges in a perforating gun to produce perforation holes in a helical pattern that is defined in part by a phase angle; and choosing four adjacent perforation holes to be created that are adjacent nearest neighbors. The distances are determined between three of the four adjacent perforation holes to be created. A standard deviation is minimized between the three adjacent perforation holes. The phase angle is set based on the minimization.

Abstract: A method and apparatus for improving reservoir communication includes, in one arrangement, use of one or more chambers to create an underbalance condition and/or a fluid surge in the wellbore. In another arrangement, a tool string comprises a packer, a circulating valve, and an atmospheric chamber, in which the circulating valve, when open, is adapted to vent a lower wellbore region below the packer when the packer is set, and the atmospheric chamber is capable of being operated to create an underbalance condition below the packer. In yet another arrangement, an apparatus comprises a subsea wellhead equipment including a blow-out preventer, choke line filled with a low density fluid, and a kill line filled with a heavy fluid. The choke line is adapted to be opened to create an underbalance condition in the wellbore.

Abstract: A process for preparing an HMX product comprises the steps of: (a) providing a granule that comprises a plurality of alpha-HMX particles and which has internal void spaces; and (b) sorbing at least one second material into the void spaces in the granule. The second material can be sorbed into the granules by using a vacuum to draw a gas phase comprising the second material into the granule. Alternatively, the second material can be sorbed into the granules by dissolving or dispersing the second material in a liquid solvent, contacting the solvent with the granules, and evaporating the solvent, whereby the second material is sorbed into the granules. Various second materials can be used, such as energetic materials and fuels.

Abstract: A novel method utilizing a new mathematical formulation for determining an optimum phase angle for phasing shaped charges in a perforating gun allows a novel perforating apparatus to be designed which phases the shaped charges by an angle equal to the optimum phase angle. Therefore, when the shaped charges detonate and a plurality of perforations are produced in a formation traversed by the wellbore, since the optimum phase angle is used to phase the charges in the perforating gun, the distances between adjacent perforations in the formation are maximized. Since such distances are maximized, the liklihood that a bridge between adjacent perforations will fail is substantially reduced.