Long term durability of the elastomers used in the high voltage underwaterelectric cables

The paper presents the behaviour of EP type rubber (inner layer of insulati ng) and PVC Nitrile type rubber (protective non-ignitible sheath) utilised for electric power-submarine cables, in sea water and mineral oil at +8 deg rees C temperature for 5 exposure years. The chemical resistance of these r ubbers were determined both from the changes of the gravimetric, thermograv imetric and physic-mechanical characteristics. The durability of these rubb ers was defined in terms of the corrosion media and efficient lifetime. The protective non-ignitible sheath of PVC Nitrile type rubber has a good resi stance in sea water and mineral oil; the inner layer of insulating of EP ty pe rubber has a good resistance in sea water and poor resistance in mineral oil, but this poor resistance is not important for the electric power-subm arine cable because the inner layer is not in contact with corrosive media; this fact can only happen when the exterior sheath of the cable would be d estroy by an accident.