Self-Sealing Electrical Cable Using Rubber Resins

Abstract

An electrical cable and a method for manufacturing the electrical cable are provided in which a plurality of insulated conductors have an inner protective layer extruded thereabout. A plurality of longitudinally extending ribs or fins or exterior ribbed or finned surfaces are formed outward of the inner protective layer between which exist a plurality of voids. An outer insulation layer can be formed in the same operation as the fins or ribbed surface and the inner layer or in a subsequent operation. A self-sealing elastomeric material is applied to the conductor surface or is present between the fins and between the inner protective layer and the outer insulation layer.

1 - 28 . (canceled) 
     
     
         29 . A method of making a self-sealing electrical cable, the method comprising:
 (a) providing a stranded conductor;   (b) forming a multi-layer flow comprising:
 an inner layer, 
 an outer layer, 
 a plurality of fins connecting the inner layer and the outer layer, and 
 a sealant material disposed between the inner layer, the outer layer, and the plurality of fins; and 
   (c) applying the multi-layer flow onto the stranded conductor;   wherein the multi-layer flow is formed prior to being applied onto the stranded conductor.   
     
     
         30 . The method of  claim 29 , wherein the stranded conductor comprises copper, aluminum, copper alloys, or aluminum alloys. 
     
     
         31 . The method of  claim 29 , wherein the self-sealing electrical cable is a 600 volt cable. 
     
     
         32 . The method of  claim 29 , wherein the inner layer comprises a thermoplastic or a thermoset. 
     
     
         33 . The method of  claim 29 , wherein the inner layer comprises a polyethylene or a PVC. 
     
     
         34 . The method of  claim 29 , wherein the outer layer comprises a thermoplastic or a thermoset. 
     
     
         35 . The method of  claim 29 , wherein the outer layer comprises a polyethylene or a PVC. 
     
     
         36 . The method of  claim 29 , wherein the sealant material comprises an elastomer material. 
     
     
         37 . The method of  claim 36 , wherein the elastomer material is a dielectric. 
     
     
         38 . The method of  claim 36 , wherein the elastomer material does not absorb moisture or swell upon contact with moisture. 
     
     
         39 . The method of  claim 36 , wherein the elastomer material has a 100 gram needle penetration value greater than 100 tenths of a millimeter at 25° C. 
     
     
         40 . The method of  claim 36 , wherein the elastomer material is a butyl rubber. 
     
     
         41 . The method of  claim 29 , wherein the sealant material comprises a flow modifier. 
     
     
         42 . The method of  claim 41 , wherein the sealant material comprises from about 25% to about 60% flow modifiers. 
     
     
         43 . The method of  claim 41 , wherein the flow modifier comprises a polyisobutene, isobutene, or a combination thereof. 
     
     
         44 . The method of  claim 29 , wherein the sealant material comprises a filler. 
     
     
         45 . The method of  claim 44 , wherein the filler comprises glass or ceramic microspheres. 
     
     
         46 . The method of  claim 29 , wherein the sealant material comprises a polyisobutene. 
     
     
         47 . The method of  claim 29 , wherein the sealant material comprises a butyl rubber, a styrene butadiene rubber, an ethylene propylene diene monomer rubber, a natural rubber, a polyolefin elastomer, or a combination thereof. 
     
     
         48 . The method of  claim 29 , wherein the sealant material comprises a butyl rubber. 
     
     
         49 . The method of  claim 29 , wherein the sealant material is flowable at about −20° C. 
     
     
         50 . The method of  claim 29 , wherein the self-sealing electrical cable has, per 50 feet of cable, initially less than about 0.2 inch shrinkback of the inner layer and the outer layer after performing a complete circular cut of the inner layer and the outer layer. 
     
     
         51 . The method of  claim 29 , wherein the self-sealing electrical cable has, per 50 feet of cable, less than about 0.5 inch shrinkback of the inner layer and the outer layer subsequent to accomplishing a complete circular cut of the inner layer and the outer layer and aging for one week. 
     
     
         52 . The method of  claim 29 , wherein the multi-layer flow is formed within a multi-layer extrusion head prior to be applied onto the stranded conductor. 
     
     
         53 . The method of  claim 29 , wherein the self-sealing electrical cable comprises 6 fins. 
     
     
         54 . The method of  claim 29 , wherein the fins comprise a portion of the inner layer and a portion of the outer layer. 
     
     
         55 . The method of  claim 29 , wherein the composition of the inner layer and the outer layer are the same. 
     
     
         56 . A method of making a self-sealing electrical cable, the method comprising:
 (a) providing a conductor comprising copper, aluminum, copper alloys, or aluminum alloys;   (b) forming a multi-layer flow comprising:
 an inner layer comprising a thermoplastic or a thermoset, 
 an outer layer comprising a thermoplastic or a thermoset, 
 a plurality of fins connecting the inner layer and the outer layer, and 
 a sealant material disposed between the inner layer, the outer layer, and the plurality of fins; and 
   (c) applying the multi-layer flow onto the conductor;   wherein the multi-layer flow is formed prior to being applied onto the conductor.   
     
     
         57 . The method of  claim 56 , wherein the sealant material comprises a polyisobutene. 
     
     
         58 . The method of  claim 56 , wherein the sealant material comprises a butyl rubber, a styrene butadiene rubber, an ethylene propylene diene monomer rubber, a natural rubber, a polyolefin elastomer, or a combination thereof. 
     
     
         59 . The method of  claim 56 , wherein the composition of the inner layer and the outer layer are the same. 
     
     
         60 . The method of  claim 56 , wherein the fins comprise a portion of the inner layer and a portion of the outer layer.