Abstract: An electric trace tube bundle characterized by an internal branched circuit or circuits wherein power to the branched circuit or circuits is supplied via leads contained within a tubular jacket surrounding an insulation layer and an inner core containing one or more process tubes and the heater circuits. Such an arrangement allows the power connection to the heater circuits to be made at a proximal end of the bundle, thereby eliminating the need to cut through the jacket to make branched circuit power connections at a location remote from the proximal end of the bundle.

Abstract: An electric trace tube bundle characterized by an internal branched circuit or circuits wherein power to the branched circuit or circuits is supplied via leads contained within a tubular jacket surrounding an insulation layer and an inner core containing one or more process tubes and the heater circuits. Such an arrangement allows the power connection to the heater circuits to be made at a proximal end of the bundle, thereby eliminating the need to cut through the jacket to make branched circuit power connections at a location remote from the proximal end of the bundle.

Abstract: Flame-retardant flexible tubing bundle construction particularly adapted for use as a conduit for the installation within a plant, building, or other facility of optical fiber cables or other signaling, sensing, or control devices. The tubing bundle construction extends in an axial direction along a central longitudinal axis to an indefinite length, and in a radial direction circumferentially about the longitudinal axis. The construction includes, typically, a plurality of plastic tube members each extending axially along the longitudinal axis and being arranged with the other tube members radially about the longitudinal axis to form a bundle. At least one thermal transfer layer may be provided to surround the tube member bundle. The thermal transfer layer, in turn, is surrounded by at least one fire-resistant layer which is formed of a fibrous material such as an aramid fiber tape.

Abstract: Flame-retardant flexible tubing bundle construction particularly adapted for use as a conduit for the installation within a plant, building, or other facility of optical fiber cables or other signaling, sensing, or control devices. The tubing bundle construction extends in an axial direction along a central longitudinal axis to an indefinite length, and in a radial direction circumferentially about the longitudinal axis. The construction includes, typically, a plurality of plastic tube members each extending axially along the longitudinal axis and being arranged with the other tube members radially about the longitudinal axis to form a bundle. At least one thermal transfer layer may be provided to surround the tube member bundle. The thermal transfer layer, in turn, is surrounded by at least one fire-resistant layer which is formed of a fibrous material such as an aramid fiber tape.