Raychem Limited

Norman A Gac

James A Rinde

Neville S Batliwalla

Len Barrett

Christian A Debbaut

Eugene F Lopez

Wendell W Moyer

Patrick K Tsou

David Terrell

Curable compositions which are useful for encapsulating electrical connections and for joining metals to metals, and which comprise a mixture of high and low molecular weight fluorocarbon elastomers. Preferred compositions comprise a mixture of three fluorocarbon elastomers, the first having a Mooney viscosity at 121.degree. C. of at least 120, the second a Mooney viscosity at 121.degree. C. of 80 to 110, and the third a Brookfield viscosity at 100.degree. C. of 1,000 to 4,000 centipoises, in amounts 5 to 50%, 25 to 70% and 5 to 50% respectively, based on the weight of the polymeric component. The compositions can be easily molded under heat and pressure, and after they have been cured, they have remarkable resistance to degradation by hot liquids, even under pressure. Consequently, the compositions are very useful in the manufacture of self-regulating heaters for use in heating the production tubes of oil wells.

Method of covering an electrical connection or cable with a

A splice between two multiconductor cables is protected from ingress of water by a closure which is filled with an expanding foam sealant which provides pressure inside the closure sufficient to force the sealant into the interstices of the splice and the interstices between the conductors in the cable, which pressure is retained in the closure until the sealant cures or hardens.

Protection of cable splice

Growing community of inventors

Palo Alto, CA, United States of America

Norman A Gac