The utilization of the laminate adhesive additionally improves the fireplace-resistance characteristics of the cable. The adhesive is coated onto the polyester film underneath comparatively low application strain and then the film and scrim are introduced together whereas in a drying oven, the scrim being beneath relatively high lengthwise tension and the coated movie being below a lesser tension, with the end result that the scrim and movie adhere tenaciously to one another. Turning now to FIG. 2, tape 14 is comprised of a 20 × 10 open weave glass fiber cloth or scrim 22. A steady movie 24 product of polyester, reminiscent of that sold under the tradename "Mylar," is bonded to the scrim utilizing a comparatively low viscosity hearth-retardant plastic laminate adhesive 26. Suitable adhesive materials include acrylic, acrylic-polyvinyl chloride copolymers and polyurethane. Consequently, when the tape 14 is wrapped on the conductor as shown in FIG. 1, it constitutes a substantially steady membrane all across the tape from one finish of the tape to the other.
Consequently, even after it has been in roll form for a comparatively very long time, the tape may be pulled from the roll without "pickoff" of the film from the scrim. Rather, the scrim 22 and coated movie 24 are maintained under different lengthwise tensions which causes the 2 to be urged collectively in the drying oven with the outcome that they develop into firmly bonded to each other. Therefore, the two layers are urged together without the glass fibers within the scrim being cracked by extreme strain. In use, the tape is wound about the clustered electrical conductors with standard filler material being provided if need be to fill the areas between the conductors so that the cable assures a typically spherical cross section. Finally, after the jacket 18 is utilized, the conductors are shielded be double steady membranes. Finally, an outer resinous jacket is extruded in situ over the taped conductors, thereby forming a second steady barrier or movie across the conductors. An outer jacket 18 of a waterproof resinous material equivalent to polyvinyl chloride, neoprene, or the like, is extruded in situ over the wrapped conductors, thus completing the cable 10. As will be seen presently, the tape 14 and jacket 18 together form a double continuous insulating barrier which is substantially impervious to moisture and the weather.
Accordingly, this invention goals to offer a tape for insulating a cable reminiscent of a service entrance cable which is relatively simple to make in uniform quality heaps. These factors further adversely have an effect on the overall insulating characteristics of the cable. That prior sort of cable is disadvantaged too as a result of the unvulcanized barrier layer is just not completely steady; it comprises pinholes which offer passages for air or moisture which adversely affect the dielectric strength of the cable insulation. These cracks tend to lower the tensile strength of the fibers. Desirably, also, a filler sixteen composed of asbestos fibers or different such material is wrapped together with conductors 12 so that it fills the spaces between the conductors, thereby giving the cable a cross part which is essentially round. Also, by virtue of the low viscosity adhesive working up between the glass fibers 22a in the scrim, the tensile strength of the tape is definitely enhanced because the adhesive seems to type a buffer between the person fibers 22a, lowering their tendency to abrade each other. Also, the unvulcanized rubber-coated glass cloth is applied to the conductors within the type of tape which is unwound from a roll.
In actual practice, the barrier layer tends to "pick off" from the cloth as the tape is unwound from the roll and it additionally undergoes a certain amount of chilly move. During this bonding course of, the coated movie and scrim aren't pressed together with any great amount of drive. When the tape is constructed in this style, the polyester movie 24 therein is substantially steady and devoid of pinholes and presents a continuous, smooth surface in order that the tape 14 may be served from a roll with out the film adhering to itself and picking off from the scrim. Moreover, the tape surface is comparatively clean. The web result is a superior insulating, bedding and binding tape which could be made at a decrease price than prior comparable merchandise and which, when integrated into an exterior cable system, enables the latter to easily cross all the UL assessments for such cables. Fire Sealing and Fire barrier for Electrical Cables and Cable Openings / Cut-Outs. The current cable has a number of distinct advantages over its typical counterparts as exemplified by the cables described within the aforesaid patents. All of these factors make the present tape a extremely successful business product whose attributes are also enjoyed by the cable system into which the tape is incorporated.
FIRE RETARDANT CABLE - CHASE CORP,US
by Paulette Carper (2025-01-13)
Consequently, even after it has been in roll form for a comparatively very long time, the tape may be pulled from the roll without "pickoff" of the film from the scrim. Rather, the scrim 22 and coated movie 24 are maintained under different lengthwise tensions which causes the 2 to be urged collectively in the drying oven with the outcome that they develop into firmly bonded to each other. Therefore, the two layers are urged together without the glass fibers within the scrim being cracked by extreme strain. In use, the tape is wound about the clustered electrical conductors with standard filler material being provided if need be to fill the areas between the conductors so that the cable assures a typically spherical cross section. Finally, after the jacket 18 is utilized, the conductors are shielded be double steady membranes. Finally, an outer resinous jacket is extruded in situ over the taped conductors, thereby forming a second steady barrier or movie across the conductors. An outer jacket 18 of a waterproof resinous material equivalent to polyvinyl chloride, neoprene, or the like, is extruded in situ over the wrapped conductors, thus completing the cable 10. As will be seen presently, the tape 14 and jacket 18 together form a double continuous insulating barrier which is substantially impervious to moisture and the weather.
Accordingly, this invention goals to offer a tape for insulating a cable reminiscent of a service entrance cable which is relatively simple to make in uniform quality heaps. These factors further adversely have an effect on the overall insulating characteristics of the cable. That prior sort of cable is disadvantaged too as a result of the unvulcanized barrier layer is just not completely steady; it comprises pinholes which offer passages for air or moisture which adversely affect the dielectric strength of the cable insulation. These cracks tend to lower the tensile strength of the fibers. Desirably, also, a filler sixteen composed of asbestos fibers or different such material is wrapped together with conductors 12 so that it fills the spaces between the conductors, thereby giving the cable a cross part which is essentially round. Also, by virtue of the low viscosity adhesive working up between the glass fibers 22a in the scrim, the tensile strength of the tape is definitely enhanced because the adhesive seems to type a buffer between the person fibers 22a, lowering their tendency to abrade each other. Also, the unvulcanized rubber-coated glass cloth is applied to the conductors within the type of tape which is unwound from a roll.
In actual practice, the barrier layer tends to "pick off" from the cloth as the tape is unwound from the roll and it additionally undergoes a certain amount of chilly move. During this bonding course of, the coated movie and scrim aren't pressed together with any great amount of drive. When the tape is constructed in this style, the polyester movie 24 therein is substantially steady and devoid of pinholes and presents a continuous, smooth surface in order that the tape 14 may be served from a roll with out the film adhering to itself and picking off from the scrim. Moreover, the tape surface is comparatively clean. The web result is a superior insulating, bedding and binding tape which could be made at a decrease price than prior comparable merchandise and which, when integrated into an exterior cable system, enables the latter to easily cross all the UL assessments for such cables. Fire Sealing and Fire barrier for Electrical Cables and Cable Openings / Cut-Outs. The current cable has a number of distinct advantages over its typical counterparts as exemplified by the cables described within the aforesaid patents. All of these factors make the present tape a extremely successful business product whose attributes are also enjoyed by the cable system into which the tape is incorporated.