Vulcanized joints and repair patches made without molds

There are several drawbacks to the conventional molding procedure of making vulcanized rubber joints and patches. The most serious one is the poor electrical quality, which in most molded rubber joints is decidedly inferior to that of the core on which they are made. Another is the known fact that a mold has to fit a particular wire rather closely. If a wide range of sizes is to be handled the cost of stoves and molds may amount to thousands of dollars. In certain applications the molding procedure is hardly feasible at all, e.g., for very small patches, or for patches on twisted heavy conductors with relatively thin insulation. In this paper a method is described which overcomes these disadvantages. The method involves the use of pressure curing types, heating being accomplished by high frequency or radiant sources.