Patent ID: 8101034

Claim:
A method for extending the useful life of at least one in-service electrical cable section having a stranded conductor surrounded by a conductor shield encased in a polymeric insulation and having an interstitial void volume in the region of the conductor, the cable section having an average operating temperature T, the method comprising: injecting a dielectric enhancement fluid composition into the interstitial void volume, the composition comprising at least one component selected from (1) a water-reactive material selected from: (i) an organosilane monomer having at least two water-reactive groups, (ii) the above organosilane monomer (i) wherein at least one of the water-reactive groups has been substituted with a condensable silanol group, (iii) an oligomer of the above organosilane monomer (i), or (iv) a co-oligomer of the above organosilane monomer (i), the organosilane monomer (i) having a diffusion coefficient at least about 15 times greater than the diffusion coefficient of its corresponding tetramer, the diffusion coefficient being determined in the polymeric insulation at temperature T; (2) a water-reactive material selected from (i) an organosilane monomer having at least two water-reactive groups, (ii) the above organosilane monomer (i) wherein at least one of the water-reactive groups has been substituted with a condensable silanol group, (iii) an oligomer of the above organosilane monomer (i), or (iv) a co-oligomer of the above organosilane monomer (i), the water-reactive material (2) having at least one group attached to silicon comprising 7 to about 20 —CH 2 — units; (3) a non-water-reactive organic material which has a diffusion coefficient of less than about 10 −9 cm 2 /sec and an equilibrium concentration of at least about 0.005 gm/cm 3 in the polymeric insulation, the diffusion coefficient and the equilibrium concentration being determined at temperature T; or (4) an organic compound having an equilibrium concentration in the polymeric insulation at 55° C. which is less than 2.25 times the equilibrium concentration at 22° C.