Schlumberger Technology Corporation

Schlumberger Well Services

Jack F Lands

Robert A Parrott

Alfredo Fayard

Haoshi Song

Wallace E Voreck

Gary M Lendermon

Janet S Denney

Dinesh R Patel

Manish Kothari

James E Brooks

Anthony Frank Veneruso

Wenbo Yang

Kuo-Chiang Chen

Jorge E Lopez De Cardenas

Brenden M Grove

Claude Jones

Larry A Behrmann

A carrier for containing explosives (e.g., shaped charges) includes a housing having a plurality of recesses, each recess having a periphery and a side surface extending around the periphery. The side surface is shaped to a geometry to reduce or control reflection of compression waves generated in response to an explosive jet (e.g., a perforating jet) created due to detonation of an explosive. The side surface may be slanted from a bottom surface of the recess, or a predetermined profile may be formed in the side surface to scatter or direct compression waves. One or more shock absorbing inserts may also be placed in recesses formed by the inserts, or the recesses may be capped to trap air so that compression waves generated in the recesses are significantly reduced as compared to compression waves generated in well fluids.

Shaped recesses in explosive carrier housings that provide for improved explosive performance

Shaped recesses in explosive carrier housings that provide for improved explosive performance in a well

A method and apparatus to protect explosive components used in various tools, such as tools for use in wellbores, includes a component with an adsorptive material. Example tools include perforating gun strings that include shaped charges, detonating cords, and booster explosives. Other tools may include surface tools containing explosive components. In these tools, a build up of corrosive gases or liquids may occur, which may cause damage to the explosive components. As a result, the structural integrity or reliability and thermal stability may be weakened or reduced. To reduce the amount of build up of corrosive gases or liquids, an adsorptive material is placed inside tools in the proximity of explosive components.

Method and apparatus of protecting explosives

An apparatus and method for sealing an inner wall of a portion of a casing positioned in a well employs an inflatable sleeve having an outer surface and a conformable composite sleeve of curable composition extending around the outer surface of the inflatable sleeve. The inflatable sleeve is inflated to compress the composite sleeve against the surface of the inner casing wall. A local, activatable energy source, positioned downhole to deliver heat to the composite sleeve, is activated to cure the composite sleeve to form a hardened sleeve. The hardened sleeve presses against the inner wall of the casing portion to create a fluid seal. The embodiments shown have a number of preferred features. The local energy source includes an exothermic heat energy source for generating heat energy to cure the composite sleeve. The composite sleeve includes a mixture of resin and a curing agent, and the exothermic heat source includes thermite. The thermite includes a composition having a metal oxide and a reductant. A starter mix is positioned adjacent the exothermic heat energy source, and the starter mix is ignited to start an exothermic reaction in the heat energy source. A conformable layer extends around the composite sleeve, with the layer serving to form a seal between the composite sleeve and the inner wall of the casing portion.

Zone isolation tools

A shaped charge for use in perforating formation adjacent a wellbore includes a liner having a substantially non-conical shape (also referred to as bowl-shaped). The liner has first and second layers, with a first layer contacting the main explosive charge. The second layer (made of such materials as copper, silver, gold, and so forth) contributes primarily to formation of a perforating jet while the first layer contains a material that substantially disintegrates upon detonation such that formation of a slug is reduced or eliminated.

Shaped charges having reduced slug creation

Sealing well casings

A perforating gun includes a multiplicity of shaped charges, the multiplicity of shaped charges including a plurality of planes of charges, each plane of charges including a plurality (N) of shaped charges and a detonating cord running down through the axial center of each of the plurality of planes of charges. The plurality (N) of shaped charges are equally spaced at an angle 360/N about the detonating cord. The plurality of planes of charges: (1) are rotated at an angle of 180/N relative to one another, and (2) are axially packed together along the longitudinal axis of the gun so that the charges in one plane are nearly touching the charges in the adjacent plane, yet they all share the same centered detonating cord. The proximity of one plane to another is close enough such that one plane of charges detonates within a few microseconds of its neighboring plane of charges. The close packing of the shaped charges in the same plane and between adjacent planes: (1) prevent the charge cases from expanding significantly upon detonation, and (2) prevent the charge cases from breaking up into numerous small pieces (large chunks of charge case debris results). A near-maximum packing density for a given cylindrical gun volume produces two unexpected properties: (1) a reduced swelling of the gun's diameter after detonation because of the combination of the near maximum packing density and symmetric detonation of the shaped charges; and (2) a significant reduction in the amount of shaped charge case debris that can escape from the perforating gun.

Perforating gun including a unique high shot density packing arrangement

In the representative embodiment of the new and improved perforating apparatus described herein, shaped charge cases are provided with matching upper and lower supports with parallel abutment surfaces and alignment means cooperatively arranged to enable a plurality of these charge cases to be stacked together for erecting an intertwined assembly of cases. By appropriately selecting the combined heights of the matching supports, adjacent ones of the charge cases can be closely spaced one above the other and directed outwardly along selected radial perforating axes at uniform angular spacings.

Shaped charge perforating apparatus

Growing community of inventors

West Columbia, TX, United States of America

Jack F Lands