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US 4,145,176 AGranted
Cable molding apparatus for accomplishing same
AssigneeTownsend and Townsend
InventorArthur L. Nelson
Life of this patent
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AssigneeTownsend and Townsend
InventorArthur L. Nelson
Estimating the term…
A method and apparatus for forming cured polyethylene insulation about high voltage cables by applying uncured polyethylene around a core of the cable. The polyethylene is heated, cured and then cooled to room temperature in a pressurized nitrogen gas atmosphere. In one form the molding apparatus comprises first and second mold forms which define a cavity and which include means for heating the mold halves to the polyethylene curing temperature. Means is also provided to introduce the pressurized nitrogen into the cavity and for subjecting cable portions that extend beyond the mold to pressurized nitrogen until such cable portions are sufficiently cooled to prevent their deformation under pressure, to prevent the oxidation of polyethylene and/or to prevent the formation of voids or enclosures. In another embodiment, the apparatus includes cooling openings for receiving a coolant preselectedly along the molding apparatus, a number of spaced-apart temperature gauges for indicating temperature at various locations along the apparatus, a pressure gauge for indicating pressure in the mold cavity, a heat source and a nitrogen source. At each end of the apparatus are recesses in which soft resilient strips are located. During the molding process, the ends of the molding apparatus are kept at a reduced temperature and the pressure in the mold cavity is varied, the nitrogen being used to pressurize the mold cavity during curing. This method insures a quality repair or splice without detracting from the quality of the cable.
Apparatus for molding insulation about a high voltage cable section including a conductive core comprising:
A mold for forming splices about short, uninsulated sections of a high voltage cable having a conductive core, the apparatus comprising first and second mold halves defining therebetween an elongated mold cavity and opposed openings concentric with the cavity communicating the latter with the exterior of the mold;
In apparatus forming insulation about an electrical cable having mold means defining a mold cavity, and means for heating an item to be molded which is positioned within said mold cavity, the improvement comprising:
Apparatus for molding insulation about a high voltage cable having a conductive core, said apparatus comprising cooperating separable mold parts defining a mold cavity for receiving a section of the cable core and with an insulated portion of the cable projecting from an end of the mold cavity, means for heating said mold to a sufficient temperature to mold insulation material placed within the cavity about the core, means for applying superatmospheric pressure to the insulation during said heating, and means for applying such superatmospheric pressure to the projected insulated portion during said heating as to inhibit the flow of insulating material in a direction from the mold cavity toward said projected insulated portion.
Dependencies are inferred from the claim text.