METHOD FOR MANUFACTURING JACK AND BODY OF JACK

摘要

The objective of the present invention is to provide a method to manufacture a jack main body capable of monitoring a lift. According to the method of manufacturing the jack main body which is inserted between a pair of bearing plates and is expanded or contracted in accordance to an injection state of an injection material; the method has a process of forming a pair of processed products by performing a spinning process to a flat steel sheet, and a process of processing the jack main body by welding end planes of the processed goods with each other. The thickness of the steel sheet is 0.8 mm or greater, and 2.6 mm or less. As such, it is easy to monitor the lift of the jack main body by being easy to change the lift of the jack main body as an internal pressure of the jack main body increases by setting the above thickness of the steel sheet. Moreover, the method is able to manufacture the jack main body by performing a spinning process to the steel sheet of the above mentioned thickness.