| 摘要 |
PURPOSE:To make the head to be molded unitarily for obtaining a bolt without coming off of the head and with excellent anticorrosion properties by a method wherein concentrated glass fiber is jointed together with thermal plastic resin to make it into a rodlike body followed by cutting it into a fixed length to heat one end thereof for deforming it by pushing and pressing. CONSTITUTION:For example, a tub 4 is filled with the solution of thermal plastic resin 3 such as hard vinyl chloride and the like and glass fiber roving 1 is made to continuously pass there-through and after squeezing by making it pass through a dice, the solvent is heated and vaporized to form core material 3. Plurality of said core materials 3 are put in order to make a core body 6, which is made to go through molten thermal plastic synthetic resin to coat its outer circumference with a thermal plastic resin layer 7 unitarily. Said core body 6 is squeezed by a die into a fixed diameter, cooled and solidified to form the true form 8 followed by being cut to a fixed length to get a rod body 9. One end thereof is pushed and pressed under heating to form the head unitarily, then the rod body 9 is provided with a screw 12 to obtain a purposed bolt. |
