Abstract: A concatenated motor assembly for providing rotational power that includes a continuous rotatable shaft cooperating with a first motor module assembly. The first motor module assembly communicates with a motor coupling unit, which in turn communicates with a second motor module. The second motor module and the motor coupling unit each cooperate with the rotatable shaft. The first and second motor modules are wound rotor electric motor. The first motor module assembly generates and provides an induced current to the motor coupling unit, which in turn provides power input to the second motor module assembly.

Abstract: A system for pumping fluid from a well-bore that includes a pump assembly driven by a first motor module assembly via a continuous rotatable shaft. The first motor module assembly includes an induction motor having a multi-phase stator and a wound rotor. Energizing the stator of the induction motor of the first motor module induces a current in the windings of the wound rotor of the induction motor of the first motor module. The induced current is supplied to a motor coupling unit which generates power to drive a second motor module assembly electrically connected to the motor coupling unit. The second motor module assembly further drives the pump assembly via the continuous rotatable shaft.

Abstract: A pre-cured proppant charge useful, for example, for propping a fracture in a subterranean formation is disclosed. The charge is made up of a large number of particles composed of a single substrate particle which can be silica sand, glass beads, or the like, coated with a thermoset resin. The thermoset resin is one which, when it is the resin coating on particles of a proppant charge, produces such a charge when the Conductivity Ratio, as defined herein, throughout a given closure stress range is greater than that of a charge of the uncoated particles. The proppant is produced by coating the particulate substrate with a suitable thermosettable resin, controlling the coating step to produce substrate particles coated with a fusible, thermosetting resin, and curing the resin by heating the coated particles, so that substantially all of the resin coated particles are composed of a single substrate particle with a thermoset resin coating thereon, prior to introduction into a subterranean well.

Abstract: A pre-cured proppant charge useful, for example, for propping a fracture in a subterranean formation is disclosed. The charge is made up of a large number of particles composed of a single substrate particle which can be silica sand, glass beads, or the like, coated with a thermoset resin. The thermoset resin is one which, when it is the resin coating on particles of a proppant charge, produces such a charge when the Conductivity Ratio, as defined herein, throughout a given closure stress range is greater than that of a charge of the uncoated particles. The proppant is produced by coating the particulate substrate with a suitable thermosettable resin, controlling the coating step to produce substrate particles coated with a fusible, thermosetting resin, and curing the resin by heating the coated particles, so that substantially all of the resin coated particles are composed of a single substrate particle with a thermoset resin coating thereon, prior to introduction into a subterranean well.

Abstract: A method is provided for propping a fracture in a subterranean formation which comprises injecting into a subterranean well a suspension in a carrier fluid of a pre-cured proppant charge, the pre-cured proppant charge being pre-cured prior to injection into the well, and comprising prior to injection into the well, resin coated sand particles most of which are composed of a single substrate particle with a thermoset resite coating thereon, the resite coating being one which, when it is the resin coating on sand particles of a proppant charge, produces a charge wherein at least one of: (a) the Conductivity Ratio thereof, throughout a given closure stress range, is greater than that of a charge of the uncoated sand particles having substantially the same particle size distribution; or (b) the Permeability Ratio thereof, throughout the stress range of about 2,000 to about 10,000 p.s.i.