An explosive downhole tool includes a housing having an upper housing part on one side of a window section and a lower housing part on an opposite side of the window section. An explosive charge is provided within the housing for at least one of cutting and expanding the wall of the tubular. The outer surface of at least one of the upper and lower housing part is rounded so as to be devoid of corners. The rounded surface eliminates the presence of sharp corners that may catch on restrictions or protrusions in a wellbore so that the downhole tool is more easily conveyable within a wellbore. Another explosive downhole tool includes fins extending from the housing. The fins have a height that decreases in a direction away from the housing. The shape of the fins enables the downhole tool to be more easily conveyable within the wellbore.

A tandem seal adapter (TSA) for use with a wellbore tool may include a TSA body including a first end and a second end opposite the first end in an axial direction, a bore extending through the TSA body from the first end to the second end, an electrical contact assembly provided within the bore, the electrical contact assembly being configured to provide electrical connectivity through the bore. The electrical contact assembly may include a bulkhead provided within the bore. An axial position of a maximum outer diameter of the TSA body may overlap with the bulkhead in the axial direction. A portion of the bore overlapping in the axial direction with an entirety of the TSA body having an outer diameter equal to the maximum outer diameter may have a constant bore diameter.

A tandem seal adapter (TSA) for use with a wellbore tool may include a TSA body including a first end and a second end opposite the first end in an axial direction, a bore extending through the TSA body from the first end to the second end, an electrical contact assembly provided within the bore, the electrical contact assembly being configured to provide electrical connectivity through the bore. The electrical contact assembly may include a bulkhead provided within the bore. An axial position of a maximum outer diameter of the TSA body may overlap with the bulkhead in the axial direction. A portion of the bore overlapping in the axial direction with an entirety of the TSA body having an outer diameter equal to the maximum outer diameter may have a constant bore diameter.

Examples relate to a mounting device for an explosive charge, comprising a first layer comprising a first foam material, and a second layer comprising a second foam material. The first layer comprises a first surface for facing a target and a second surface adjoining the second layer. The second layer comprises a recess for receiving at least one of the explosive charges.

Examples relate to a mounting device for an explosive charge, comprising a first layer comprising a first foam material, and a second layer comprising a second foam material. The first layer comprises a first surface for facing a target and a second surface adjoining the second layer. The second layer comprises a recess for receiving at least one of the explosive charges.

A box by pin perforating gun system using swaged down gun bodies, a removable cartridge to hold a detonator and switch, and an insulated charge holder as an electrical feed-through.

A box by pin perforating gun system using swaged down gun bodies, a removable cartridge to hold a detonator and switch, and an insulated charge holder as an electrical feed-through.

An assembly (7) for triggering an explosive in a hole (9) to produce an explosive blast in the hole includes (a) an explosion trigger (15, 19) for triggering the explosive in the hole, (b) a detonation unit body (21) that is configured to be located at or proximate an open end of the hole in an initial position of the assembly in the hole and (c) a trigger cord (31) that is connected to the detonation unit body and to the explosion trigger.

An assembly (7) for triggering an explosive in a hole (9) to produce an explosive blast in the hole includes (a) an explosion trigger (15, 19) for triggering the explosive in the hole, (b) a detonation unit body (21) that is configured to be located at or proximate an open end of the hole in an initial position of the assembly in the hole and (c) a trigger cord (31) that is connected to the detonation unit body and to the explosion trigger.

A blasting system which includes control equipment and a plurality of detonators which are located in respective boreholes formed in rock, wherein signals from the detonators are magnetically transmitted wirelessly through the rock to the control equipment via different paths between successive detonators, and wherein a signal from the control equipment can be simultaneously transmitted to all of the detonators.