James L Hawkins

US Patent:

47360712, Apr 5, 1988

Filed:

Jun 3, 1987

Appl. No.:

7/059211

Inventors:

James B. Hawkins - Loganville GA
Thomas V. Lathrop - Dunwoody GA
William S. Pesto - Alpharetta GA

Assignee:

American Telephone and Telegraph Company, AT&T Bell Laboratories - Murray Hill NJ

International Classification:

H02G 15113

US Classification:

174 92

Abstract:

The long term water intrusion resistance of cable splice systems that use a gelable encapsulant that is pressurized prior to geletion can be improved by providing pressurization means that maintain the pressure on the cured encapsulant above a given pressure p. sub. 2 >p. sub. o, where p. sub. o is the ambient pressure. Absent such pressurization means, the pressure on the encapsulant typically decreases with time due to creep or relaxation of nominally rigid components, e. g. , a polymeric closure around the encapsulated splice, or varies due to differential thermal contraction. The pressurization means comprises one or more energy storage elements, e. g. , an elastic member such as a spring, or a volume of compressed gas. In a preferred embodiment, an elastomeric "bag" is formed around the completed cable splice, the two halves of a plastic closure placed around the bag, the two halves fastened together with a spring clamps, liquid encapsulant introduced into the bag, and the encapsulant pressurized to a pressure p. sub. 1 >p. sub. 2. The spring clamps typically are dimensioned such that a gap exists between the two halves of the plastic closure for any pressure. gtoreq. p. sub.