| 摘要 |
The present invention relates to a float manufacturing method comprising a correction step. With regard to the manufacturing method of a float having a hole through which a rope passes inside, the float (40) is manufactured by making an upper mold and a lower mold in a form of the float; and injecting a molten synthetic resin solution including polyethylene (PE) into the upper mold and the lower mold, wherein the molten synthetic resin solution including polyethylene is injected into a float-shaped mold and injection molding is performed. The mold used is reduced in size when compared to a main body to be manufactured. During an injection molding step, only the polyethylene, which is a synthetic resin, is molten in a temperature where the foaming and cross-linkage of raw materials for the float (40) do not be formed. The main body manufactured by injection molding is placed in a foaming machine, and then the main body is heated to the reaction initiation temperature of a cross-linking agent and a foaming agent which are included in the main body when the foaming machine is sealed. Accordingly, a firm polymer bond is formed in the main body due to the reaction of the cross-linking agent while the volume of the main body is entirely expanded due to the reaction of the foaming agent. The float (40) molded through a cross-linking step and a foaming step passes through a correction step. The correction step is to insert the float (40) molded through the cross-linking step and the foaming step into a correction mold (100), followed by correcting the float (40). The float (40) in the present invention is made from polyethylene and has remarkable effects of having enhanced dimensional accuracy and being made totally balanced through the correction step of correcting the float (40) which has passed through the molding step, the cross-linking step and the foaming step. |
