Abstract: There is disclosed, according to the present invention, an apparatus and method for loading explosives exhibiting little water resistance into water filled blast holes without contamination of the explosives by water. A pressure charger vessel, capable of being filled with bulk explosives of low density and low water resistance, such as ammonium nitrate fuel oil, is connected to a flexible plastic sleeve. A pneumatic plug fixedly connects the lower portion of the pressure charger vessel to the plastic sleeve. The plastic sleeve is lowered into a blast hole by means of a weight. Compressed air is then introduced into the pressure charge vessel and a valve means located between the sleeve and the pressure charger vessel is opened, permitting pressurized ammonium nitrate fuel oil to be pushed downwardly into the flexible plastic sleeve. Projections and recesses on the outer surface of the plastic sleeve facilitate the expulsion of water from the blast hole.

Abstract: A locking device for a pin and socket interconnection of tubular well tool housings where a locking mechanism has a first rotatably mounted annular locking member on a second locking member on a pin end. The locking members have cooperating cam surfaces and locking segments which can be moved from a non-engaged position to our engaged position within a locking groove in a socket member. The locking members are actuated by relative rotation and also have a guide slot system for contemporaniously driving the pin end and socket member longitudinally relative to one another to a position compresssing O-rings between the pin end and socket member and a locked position of the pin end and socket member.

Abstract: In accordance with illustrative embodiments of the present invention as disclosed herein, a safety switch for preventing accidental firing of an explosive well tool includes a tubular metal body connected between the cable head and the well tool, a conductor wire extending through such body for carrying current from the cable to the well tool, and a contact plug mounted in a slide opening in the body and arranged to be selectively advanced into shorting contact with the conductor wire.

Abstract: A cartridge for the expulsion of liquids under pressure, including a chamber for a propellent charge and a separating arrangement which is located intermediate the chamber for the propellent charge and a liquid chamber. The separating arrangement is constituted as a propulsion mechanism which consists of a driving member, and a closure element which is detachably connected therewith at the end surface of the former.

Abstract: A method for the driving of steel profiles into a rock substratum is described, in which, before the driving, holes are drilled into the rock substratum, in which holes explosive charges are detonated. The explosive charge is so constructed and dimensioned that only the shock waves of the explosion act upon the rock, and not the combustion gases, so that the rock is only shattered in its internal structure but is not driven away. In the construction of a sheet pile wall, the holes are provided with explosive in mutually overlapping zones of differing depths, zones of the same depth being detonated at the same time and the charge in each hole being provided at top and bottom with a detonator each.

Abstract: A method and apparatus for releasing a subterranean well perforating gun from a tubular string after firing of the subterranean well perforating gun. The apparatus comprises two telescopically inter-related tubular assemblies which are interconnected for axial co-movement solely by a plurality of radially shiftable latching elements. Such latching elements are normally maintained in a locked position by an annular piston. One end of the annular piston is exposed to gas at surface ambient pressure and the other end is exposed to the gas pressure generated in the perforating gun by its discharge and subsequently to the well fluid pressures produced by flow of well fluids through the perforations. The movement of the annular piston under such fluid pressure forces permits the locking elements to be cammed radially inwardly and release the connection between the tubular tool string and the perforating gun without any action on the part of the operator.

Abstract: The invention provides for a drill unit for drilling and charge laying operations and is suitable for operation on land or underwater. The drill unit comprises a rock drill mounted on a frame structure on a gantry and drill steels and casing members located in a drill magazine where they can be moved into register with the drilling machine for drilling a hole below the gantry, the casing member being put down the hole to line it and a charge magazine containing explosive cartridges also mounted on the gantry provided with means for bringing a cartridge into register with a casing member put down a hole to charge the casing member. The operation being remotely controlled.

Abstract: A projectile having a length to diameter ratio greater than 6 to 1 is propelled from a launcher by a propellant charge toward a rock target at velocities of 500 ft./sec. and higher to more efficiently penetrate the rock for excavation purposes.

Abstract: The configuration and directional orientation of natural or induced fractures in subterranean earth formations are described by introducing a liquid explosive into the fracture, detonating the explosive, and then monitoring the resulting acoustic emissions with strategically placed acoustic sensors as the explosion propagates through the fracture at a known rate.