Preparation mold of socket and spigot type pipeline sealing ring and use method of preparation mold

The invention discloses a preparation mold of a socket and spigot type pipeline sealing ring. The preparation mold comprises an upper mold having an upper mold ring cavity and defined by sequentially connecting an upper mold first outer ring concave surface, an upper mold second inner ring concave surface, an upper mold third inner ring conical surface, an upper mold fourth inner ring conical surface and an upper mold fifth inner ring surface; a lower mold provided with a lower mold ring cavity and defined by sequentially connecting a lower mold first outer ring surface, a lower mold second outer conical surface, a lower mold third ring bottom surface and a lower mold fourth inner ring surface; the abutting part of the upper mold first outer ring concave surface and the lower mold first outer ring surface is an inner ring parting surface; and the abutting part of the upper mold fifth inner ring surface and the lower mold fourth inner ring surface is an outer ring parting surface. Meanwhile, the invention furt