Apparatus for manufacturing composite insulators

A seat forming member for a mold assembly for manufacturing a composite insulator, said composite insulator comprising a core rod, a sheath covering the core rod over substantially the entire length thereof, and a plurality of sheds projecting radially outward from the sheath and spaced from each other in a longitudinal direction of the core rod, said core rod having a longitudinal end portion provided with a seat that is integral with the sheath and to which a metal fitting can be fixedly secured, and

• said mold assembly being comprised of a pair of mold halves defining a mold cavity therebetween, said mold cavity being arranged so that said core rod can be placed therein, said seat forming member comprising:
• a first inner surface that can be tightly laid over the outer surface of the core rod, with a sealing member interposed therebetween;
• a second inner surface that can be radially spaced from the outer surface of the core rod to define said inner space;
• said first inner surface being arranged on a side that is remote from the mold cavity, and said second inner surface being arranged on a side which is close to said mold cavity;
• and
• said seat forming member being adapted to be detachably fitted to the end portion of the core rod and arranged between the mold halves such that an inner space is formed between an inner surface of the seat forming member and an outer surface of the core rod;
• said inner space being in communication with the mold cavity so that an electrically insulating polymeric material, when introduced into the mold cavity to form said sheath and said sheds, is admitted into said inner space so as to form said seat for the metal fitting.