■ Blanking (according to the drawing or sample, calculate the total length of forged bolt through 3DMAX)
■ Chamfering and central hole drilling (the threaded part needs to be reduced or machined before the thread can be extruded by the thread rolling wheel)
■ Red punch forging of bolt head (use high-frequency furnace to heat the round steel and pay attention to heating time, and then use friction press or punch to forge bolt head through die to form; consistent with customer's sample or drawing requirements)
■ edge cutting / deburring (because there is redundant oxide skin when the screw head is forged, it needs to be processed by the instrument or lathe, and the surface should be smooth)
■ Thread rolling, collectively referred to as thread rolling (use the thread rolling machine to extrude the required thread through the thread rolling wheel)
■ Heat treatment process (generally including heating, heat preservation and cooling) GB / t7232-1999
■ Pickling (remove the oxide skin on the surface of the screw by pickling, so as to make the surface smooth and beautiful)
■ Blackening (using the residual heat Blackening Technology, put the screw into the blackening furnace to blacken, the screw surface has a layer of black color, to prevent screw oxidation, and the surface is beautiful)
■ Packaging (domestic - carton + wooden pallet / wooden box + wooden pallet for export).
