HYDROFORMING PROCESSING METHOD OF A STEEL PIPE WITHOUT USING AN ADDITIONAL HIGH FORMING MATERIAL WHICH IS NORMALLY USED IN HYDROFORMING PROCESSING

摘要

PURPOSE: A hydroforming processing method of a steel pipe is provided to inject high temperature liquid inside a steel pipe when the steel pipe is pressurized, thereby facilitating the forming of various kinds of steel pipes at a low pressure by the use of two-way pressure between an upper mold and the high temperature liquid.;CONSTITUTION: A hydroforming processing method of a steel pipe comprises the following steps. A steel pipe is placed on the upper end of a lower mold(S100). An upper mold descends to a fixed height and begins to pressurize the steel pipe(S200). A high temperature liquid is injected into the inside of the pressurized steel pipe(300). The forming of the steel pipe is completed by the use of the two-way pressure between the high temperature liquid injected inside the pressurized steel pipe and the descending upper mold(400). The upper mold is lifted up and the steel pipe completed with forming is released(500).;COPYRIGHT KIPO 2013;[Reference numerals] (AA) Start; (BB) End; (S100) Inserting a steel pipe to the upper end of a lower mold; (S200) Pressurizing the steel pipe by lowering an upper mold to a predetermined height; (S300) Injecting a high-temperature liquid into the pressurized steel pipe; (S400) Forming the steel pipe using a bidirectional pressure between the high-temperature liquid and the upper mold; (S500) Separating the completely formed steel pipe by raising the upper mold;