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The invention accordingly includes the several steps and the relation of such steps with every of the others and the options of construction, mixture of components and arrangement of elements which will likely be exemplified in the construction hereinafter set forth and the scope of the invention might be indicated in the claims. FIG. 2 is a scrap view with parts damaged away showing the bedding and binding tape in the FIG. 1 cable in greater detail. An additional object of the invention is to offer a bedding and binding tape which is comparatively economical to manufacture. Therefore, the thickness and, therefore, weight of the tape as a whole are less than these of typical service entrance cable tape incorporating a pure or synthetic rubber barrier layer which is calendered immediately onto the scrim. Consequently, even after it has been in roll form for a comparatively long time, the tape may be pulled from the roll with out "pickoff" of the movie from the scrim. Also, the unvulcanized rubber-coated glass cloth is applied to the conductors in the type of tape which is unwound from a roll. In actual observe, the barrier layer tends to "decide off" from the cloth because the tape is unwound from the roll and it additionally undergoes a specific amount of chilly stream.

To make the tape, the relatively low viscosity adhesive 26 is coated onto the polyester movie using a standard coating roll set for minimum applied stress. Turning now to FIG. 2, tape 14 is comprised of a 20 × 10 open weave glass fiber cloth or scrim 22. A steady film 24 fabricated from polyester, similar to that offered beneath the tradename "Mylar," is bonded to the scrim using a relatively low viscosity fireplace-retardant plastic laminate adhesive 26. Suitable adhesive supplies embody acrylic, acrylic-polyvinyl chloride copolymers and polyurethane. It has been discovered that the glass fibers in scrim tend to crack when subjected to high pressures resembling these encountered throughout a typical calendering operation. A barrier layer in the form of a skim coat of flame-retardant unvulcanized polychloroprene is calendered on the glass cloth and finally an outer jacket of synthetic rubber is extruded in place onto the tapered conductors and fused to the underlying barrier layer. An outer jacket 18 of a waterproof resinous material reminiscent of polyvinyl chloride, neoprene, or the like, is extruded in situ over the wrapped conductors, thus completing the cable 10. As can be seen presently, the tape 14 and jacket 18 together form a double steady insulating barrier which is considerably impervious to moisture and the elements.

Finally, an outer resinous jacket is extruded in situ over the taped conductors, thereby forming a second steady barrier or movie around the conductors. DC68 Spray to guard retards fire and prevents the spread of flame over the treated area. DC68 Spray to protect won't affect look, really feel or ventilation . That prior sort of cable is disadvantaged too because the unvulcanized barrier layer is not completely continuous; it accommodates pinholes which provide passages for air or moisture which adversely have an effect on the dielectric energy of the cable insulation. It relates extra significantly to fire-retardant insulation in sheet and tape type for cables which are uncovered to the weather and which must be capable of withstand rough utilization, e.g. a service entrance cable. This invention relates to electrical cable. In use, the tape is wound about the clustered electrical conductors with conventional filler materials being supplied if need be to fill the spaces between the conductors in order that the cable assures a usually round cross part.

Turning now to the drawing FIG. 1, a piece of service entrance cable is proven generally at 10. Cable 10 is comprised of a cluster, herein three, of insulated stranded conductors 12. Special cable insulation tape 14 to be described presently is helically wrapped about the clustered conductors 12 with the adjacent turns of the tape overlapping one another. Desirably, additionally, 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 section which is essentially spherical. That extra step, coupled with the truth that a full crew is required to calender the fabric onto the glass cloth, means that the general cost of the prior cable is higher than need be. These elements further adversely affect the general insulating characteristics of the cable. It's believed that this is due primarily to 2 components. Medium and heavy weight fabrics: Needs to be sprayed two or extra instances on each facet.