Preparation method of pillar porcelain core composite insulator

Abstract

The invention discloses a preparation method of a pillar porcelain core composite insulator. The preparation method comprises the following steps: 1) installing flanges (2) at two ends of a porcelain core (1); 2) the outer circular surfaces of the two ends of the porcelain core (1) are used as sealing surfaces of a forming die, a sheath (3) and an umbrella skirt (31) are integrally formed on the porcelain core (1), during forming, the forming die is not in contact with the flange (2), and after forming, a gap is formed between the inner end surface of the flange (2) and the end part of the formed sheath (3); and 3) coating and sealing a gap between the inner end surface of the flange (2) and the end part of the sheath (3) through room temperature vulcanized silicone rubber. The method can effectively prevent the flange from bearing high temperature, even if the flange and the porcelain core are not coaxial, the thickness of the sheath on different outer circular surfaces of the porcelain core is not consistent, and a plating layer on the outer surface of the flange does not need to be damaged.

Description

technical field [0001] The invention relates to the technical field of electric ceramics, in particular to a preparation method of a pillar ceramic core composite insulator. Background technique [0002] The pillar ceramic core composite insulator mainly includes a rod-shaped ceramic core made of ceramic material, metal flanges located at both ends of the ceramic core, a silicone rubber sheath and an umbrella skirt set on the sidewall of the ceramic core; the metal flange is used for the connection between the insulators Or installation, the sheath and shed made of silicone rubber are vulcanized to the ceramic core by means of high temperature vulcanization, and the ceramic core bears the main mechanical stress. pollution ability. [0003] In the prior art, because the metal flange and the ceramic core need to have a high bonding strength and at the same time effectively prevent the ceramic core wrapped by the metal flange from bursting due to the expansion stress, this typ...

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Problems solved by technology

[0005] 1) Since part of the metal flange needs to be wrapped in a high-temperature injection vulcanization mold, and the vulcanization temperature of high-temperature vulcanized silicone rubber is generally 130-170°C, metal flanges and cement glue should be used for high-temperature vulcanized silicone rubber sheaths and sheds Directly subjected to high temperature, when the cement glue is cured, the residual moisture inside evaporates and vaporizes, which causes the cured cement glue to generate greater internal stress, reduces the strength of the cement glue, and then reduces the mechanical properties of the insulator; if the vaporized water vapor enters the sheath and the ceramic core The bonding area of ​​the insulator will directly reduce the insulation performance of the insulator, causing a safety hazard in the insulator

[0006] 2) Since there is a gap of 7-10mm between the inner wall of the metal flange and the outer wall of the ceramic core, the ceramic core is made of ceramic material fired from clay, and the diameter tolerance is large. The ceramic core and the metal flange It is very easy to cause the metal flange and the ceramic core to be out of axis during the process of bonding with cement adhesive, and the above-mentioned sealing process that requires the vulcanization mold to wrap part of the metal flange must use the outer peripheral surface of the metal flange as the mold sealing surface, resulting in The metal flange is coaxial with the mold cavity but the ceramic core is not coaxial with the mold cavity. When injecting vulcanized silicone rubber, the thickness of the sheath on different outer surfaces of the ceramic core is inconsistent, and the part of the sheath that is too thin is easy to break during use. , which in turn causes moisture and impurities to penetrate into the joint surface of the ceramic core and the sheath, destroying the joint layer and causing erosion and degumming. Long-term development will lead to breakdown accidents along the joint surface

[0007] 3) The metal flange has a galvanized layer. The traditional metal flange positioning mold solution needs to open a stepped surface and a dovetail groove on the outer surface of the metal flange to form and anchor a certain thickness of high-temperature vulcanized silicone rubber. The depth of the dovetail groove is too large. Small, it will lead to insufficient anchoring force of high-temperature vulcanized silicone rubber, and the depth of the dovetail groove is too large, which will reduce the thickness of the metal flange cap, reduce the strength of the metal flange, and the stepped surface and dovetail groove damage the galvanized layer of the metal flange , reduce the corrosion resistance of the product; high-temperature vulcanized silicone rubber has a large curvature at the edge of the metal flange, poor weather resistance, and is prone to aging, cracking and curling under the wind and sun

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