Abstract: A method of managing a liquid solvent inventory in a condensing solvent gravity drainage extraction chamber includes growing the extraction chamber by injecting a solvent vapour under conditions which cause at least a portion of the solvent vapour to condense on a hydrocarbon extraction interface at a condensation temperature, then accumulating within the extraction chamber condensed liquid solvent which is draining through the chamber under the influence of gravity, which liquid solvent includes a hydrocarbon rich fluid production layer which is proximal to said extraction interface, and then heating a portion of the extraction chamber from a location near, in and/or above the injector to create a heated zone having a temperature above the condensation temperature without heating the hydrocarbon rich production layer to permit the hydrocarbon rich production layer to continue to drain to a production well.

Abstract: A separable junction for an electric pipeline system of the type including a tracer for skin-effect heating, which tracer comprises an insulated conductor within an electrically conductive conduit, incorporates flanges at the ends of the pipe section to be joined and the pipes are joined by securing bolts through holes in the flanges. Each end of the tracer conduit on each of the sections of pipe is terminated at and electrically connected to a metallic junction box adjacent to a flange and the tracer conductor thereof extends into the box. Each box has an opening aligned with one of the flange holes for the fastening bolts, but when the junction is assembled, the flange bolt which would be in alignment with the junction box opening is replaced with a hollow, threaded metallic nipple which is dimensioned to fit freely through the bolt holes in the flanges and is long enough to extend between and into the openings of the junction boxes at either side of the junction and electrically connect the boxes.

Abstract: Faster and more efficient heat transmission between an electrical skin effect current heat generating unit and the surface of a pipe to be heated is achieved by utilizing convective as well as conductive transfer of heat therebetween. The unit includes an elongated ferromagnetic channel having an open face and secured along its longitudinal edges by staggered stitch welds to the surface of a ferromagnetic pipe to be heated. The inner surface of the channel and the confronting outer surface of the pipe define an air space at least partially surrounding a freely movable insulated conductor having one end connected to a pole of an AC source and its other end connected to the far end of the channel. The near end of the channel is connected to the other pole of the AC source.

Abstract: An electrical heat generating system of the skin effect current type having a two part elongate hollow element of ferromagnetic material enclosing an insulated energizing conductor. One part of the hollow element comprises an open face channel having two elongated, coextensive, spaced longitudinal edges and the other part covers the open face of the channel. When the conductor is energized by an alternating current, the magnetic field generated thereby is confined within the interior of the hollow element to produce heat without any current passing through and along the outer peripheral surfaces thereof.