Abstract: Described herein are methods and system that use electromagnetic heating to heat wellbores and the fluids therein. The heating is achieved by placing one or more permanent magnets in the wellbore and moving a metallic component and/or the one or more permanent magnets relative to each other. This generates eddy currents in the metallic component, which heat the metallic component. This heat is transferred to the fluids in the wellbore from the metallic component by convection.

Abstract: Described herein are methods and system that use electromagnetic heating to heat wellbores and the fluids therein. The heating is achieved by placing one or more permanent magnets in the wellbore and moving a metallic component and/or the one or more permanent magnets relative to each other. This generates eddy currents in the metallic component, which heat the metallic component. This heat is transferred to the fluids in the wellbore from the metallic component by convection. In some embodiments, permanent magnets are installed in the tubing to induce eddy current heating in a well by converting the linear motion of a sucker rod to rotary motion of a conducting tube using a lead or ball screw. The heater may directly integrate with existing pump jack equipment with little or no additional infrastructure required.

Abstract: Described herein are methods and system that use electromagnetic heating to heat wellbores and the fluids therein. The heating is achieved by placing one or more permanent magnets in the wellbore and moving a metallic component and/or the one or more permanent magnets relative to each other. This generates eddy currents in the metallic component, which heat the metallic component. This heat is transferred to the fluids in the wellbore from the metallic component by convection. In some embodiments, permanent magnets are installed in the tubing to induce eddy current heating in a well by converting the linear motion of a sucker rod to rotary motion of a conducting tube using a lead or ball screw. The heater may directly integrate with existing pump jack equipment with little or no additional infrastructure required.

Abstract: Described herein are methods and system for welding, for example, girders. The method may include activating a homopolar generator. The method may include applying a force to two metal girders at a desired coupling joint. The method may include generating an electrical pulse using the homopolar generator and conducting the electrical pulse to the desired coupling joint to increase a temperature of the girders. The method may include forming a weld at the desired coupling joint attaching the two metal girders at the desired coupling joint. In some embodiments, the homopolar generator may include a radial bearing rotor including a rotatable shaft and a bearing assembly. The bearing assembly may include nonmagnetic bearings. The homopolar generator may include a field coil. The homopolar generator may include a brush actuation mechanism which when activated engages a plurality of brush devices to the radial bearing rotor.

Abstract: Described herein are methods and system that use electromagnetic heating to heat wellbores and the fluids therein. The heating is achieved by placing one or more permanent magnets in the wellbore and moving a metallic component and/or the one or more permanent magnets relative to each other. This generates eddy currents in the metallic component, which heat the metallic component. This heat is transferred to the fluids in the wellbore from the metallic component by convection.

Abstract: Aspects described herein relate to an electromagnetic seismic vibrator (EMSV) architecture that provide wide frequency range operation, ground force application with high fidelity, and low environmental impact. The EMSV architecture can include a base member that can support a force coil and mitigate electrical heating due, at least in part, to spurious currents. The EMSV architecture can include means for restricting movement of a reaction member included in the EMSV architecture relative to the base member. Such means can permit mitigation of damage of the EMSV architecture in scenarios in which control of the EMSV architecture may fail.

Abstract: Aspects described herein relate to an electromagnetic seismic vibrator (EMSV) architecture that provide wide frequency range operation, ground force application with high fidelity, and low environmental impact. The EMSV architecture can include a base member that can support a force coil and mitigate electrical heating due, at least in part, to spurious currents. The EMSV architecture can include means for restricting movement of a reaction member included in the EMSV architecture relative to the base member. Such means can permit mitigation of damage of the EMSV architecture in scenarios in which control of the EMSV architecture may fail.

Abstract: The present invention provides a method for depositing powder particles on a substrate. The method comprises forming a planar plasma armature, accelerating the plasma armature, accelerating a column of gas with the plasma armature; and accelerating the powder particles with the column of gas. The present invention provides for a railgun, comprising first and second conducting rails, and first and second insulating rails. The insulating and conducting rails form a bore of the railgun. The first and second conducting rails are separated by the insulating rails. At least one of the rails has a port in the wall thereof, the port is adapted to introducing powder particles into the bore.

Abstract: The present invention provides a method for depositing powder particles on a substrate. The method comprises forming a planar plasma armature, accelerating the plasma armature, accelerating a column of gas with the plasma armature; and accelerating the powder particles with the column of gas. The present invention provides for a railgun, comprising first and second conducting rails, and first and second insulating rails. The insulating and conducting rails form a bore of the railgun. The first and second conducting rails are separated by the insulating rails. At least one of the rails has a port in the wall thereof, the port is adapted to introducing powder particles into the bore.

Abstract: An apparatus and method are provided for controlling the switching characteristics of an explosively actuated switch. The switch comprises a conductor that is only partially severed by explosive forces. A bridge region, the conductive portion of the conductor remaining after the explosion, is then severed by thermal breakdown. Variations in the bridge region enable a user to vary the switching characteristics of the switch.

Abstract: A railgun operates at high pressure (up to 350 MPa) without structural damage and is readily disassembled for inspection, maintenance and component testing. A rail assembly is pressed into a hoop-wound epoxy fiberglass containment tube and clamped within a steel compression frame. The geometry of the rail assembly permits rail movement without insulator intrusion and achieves bore sealing during rail movement at maximum pressure. The rail assembly also has replaceable insulator inserts which are isolated from rail re-bound shock. Fused quartz insulator inserts provide the best results. A flash tube is provided at the gun muzzle to suppress precursor discharge and commutate precursor current back to the armature. To realize increased velocity without sacrificing in-bore projectile stability, a cut-corner projectile is used having a L/D ratio as small as 0.65 which reduces the mass by about 11%.

Abstract: A staged switch for conducting a large electrical current for an indefinite time period and then rapidly switching the current into a load circuit. The switch comprises a first stage which can conduct a large electrical current for an indefinite time period without damage to the stage and a second stage which is a fast-opening element. The first stage includes primary and secondary contacts wherein the primary contacts conduct a charging current and the secondary contacts divert the current into the fast-opening second stage. The secondary contacts "make" before the primary contacts "break", reducing the damage to the contacts which might otherwise be experienced. The second stage is a low-inductance element which reduces the level of energy absorbed by the first-stage contacts, minimizing damage to the contacts. The second-stage element may be constructed in a cartridge and may be loaded into the switch using an autoloader device.

Abstract: A welding fixture by which two elongate members are manipulated in a manner to become butt welded together. Two gripping members in the form of groups of spaced slip assemblies are enclosed in mounted relationship within a housing. The slips of each group circumferentially extend about a longitudinal axis of the housing, with the slips of each group being radially spaced from the longitudinal axis of the members to be joined. A first group of slips are mounted for movement within a plane which is perpendicular to the longitudinal axis of the members to be joined. The other group of slips are likewise arranged within a plane spaced from and parallel to the first plane. All of the slips are moved with great force towards the longitudinal axis of the members to be joined. The fixture includes means by which the members are moved toward one another with great force. Each group of slips further include an electrical contact which provides a source of current to each of the members to be joined.