A tandem seal adapter for a perforating gun assembly includes a housing having a first end adapted to be connected to a first perforating gun and a second end adapted to be connected to a second perforating gun. A port extends through a wall of the housing and is in communication with an interior of the first perforating gun. A tracer material is arranged in the port, and a retainer secures the tracer material in the port. Upon detonation of the first perforating gun, the retainer is displaced and the tracer material is expelled from the port by gas pressure produced by the detonation. A corresponding method of using a tandem seal adapter to disperse tracer material into a wellbore and a tool string employing such a tandem seal adapter are also provided.

The way in which a fiber optic cable is wrapped around a casing string in a wellbore can be modeled using information from downhole sensor devices. For example, a system can include a fiber optic cable located along a length of a wellbore. The system can also include sensor devices located near the fiber optic cable at various depths to transmit acoustic signals indicating depths and orientations of segments of the fiber optic cable. The system can build a model describing how the fiber optic cable is positioned around the casing string based on the acoustic signals transmitted from the sensor devices. The system can also determine a target position for a perforating gun to perform a perforation operation through the casing string that avoids damaging the fiber optic cable. The system can output the target position for the perforating gun to an electronic device to facilitate the perforation operation.

A method, downhole tool, and system, of which the method includes deploying a perforation charge into a wellbore, signaling the perforation charge to detonate, deploying a cable into the wellbore, determining a fluid flow rate at a predetermined location in the wellbore using the cable, and determining whether the perforation charge detonated at the predetermined location based on the fluid flow rate.

The disclosure relates to perforating systems for perforating the casing of a wellbore. The perforating systems contain insensitive high explosives. The disclosure also relates to shaped charges containing insensitive high explosives for use in such perforating systems. The disclosure further relates to methods of using such perforating systems to perforate the casing of a wellbore

The disclosure relates to perforating systems for perforating the casing of a wellbore. The perforating systems contain insensitive high explosives. The disclosure also relates to shaped charges containing insensitive high explosives for use in such perforating systems. The disclosure further relates to methods of using such perforating systems to perforate the casing of a wellbore.

A non-addressable switch device that is part of a chain of switch devices in a gun string, the non-addressable switch device including a first switch configured to make an electrical connection between an electrical line and another non-addressable switch device of the chain of switch devices; a second switch configured to make an electrical connection between a detonator and the electrical line; and a processor P.sub.A connected to the first and second switches and configured to close and open the first and second switches. The processor P.sub.A is configured to not use a digital address, and the processor P.sub.A is configured to perform one of plural functions based on a corresponding pulse received along the electrical line.

A wireline release tool for downhole intervention, the tool including a housing having an electrical input and an electrical output; a pass-through switch located inside the housing and electrically connected between the electrical input and the electrical output; and a current limiter device located inside the housing and electrically connected between the electrical input and the electrical output. The pass-through switch is connected in parallel to the current limiter device, between the electrical input and the electrical output

A wireline release tool for downhole intervention, the tool including a housing having an electrical input and an electrical output; a pass-through switch located inside the housing and electrically connected between the electrical input and the electrical output; and a circuit limiter device located inside the housing and electrically connected between the electrical input and the electrical output. The pass-through switch is connected in parallel to the circuit limiter device, between the electrical input and the electrical output.

The present invention is directed toward an addressable ignition stage which produces an output sufficient to detonate a secondary explosive, generally. The present invention comprises addressability and ignition functions that may be used together or separately to incorporate a high-power resistor with a thermally conductive substrate allowing for operation at high temperatures for ignition. The ignition stage is amendable to high volume production, exhibits a high degree of reliability, robustness and operational dependability for use alone or configurable into existing technology.

A control module for a detonation sub includes a control circuit having a switch, a power supply input, a timer circuit, and a detonation signal output electrically connected to a detonator. A power supply is selectively connected in electrical communication to the power supply input. A timer circuit is initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time. Once initialized, the timer circuit generates a detonation signal after a detonation time.