Cold heading and cold extrusion are basically deformation processing under the same conditions, but the operation mode is different. Cold pier belongs to the forging deformation of small workpieces and is often used in fastener industry. Cold extrusion belongs to the extrusion deformation of larger workpieces, which is widely used.
What is cold extrusion?
Cold extrusion is the processing method of putting the metal blank in the cold extrusion die cavity and applying pressure to the blank through the punch fixed on the press at room temperature to make the metal blank produce plastic deformation. Cold extrusion is one of the processing technologies of parts with no chip and less chip.
At present, cold extrusion technology has been widely used in fasteners, machinery, instruments, electrical appliances, light industry, aerospace, shipbuilding, military and other industrial departments, and has gradually become the development direction of refined production of small and medium-sized forgings.
Cold extrusion is also divided into forward extrusion, reverse extrusion, compound extrusion, radial extrusion and so on.
What is cold heading?
Cold heading process is a processing method that uses the plastic deformation of metal under the action of external force and makes the metal volume redistribute and transfer with the help of die, so as to form the required parts or blanks. Cold heading process is most suitable for producing standard fasteners such as bolts, screws, nuts, rivets and pins. The common die used in cold heading process is cold heading die.
Cold heading technology is more and more widely used in mechanical manufacturing, especially in the production of standard fasteners. The most representative products produced by multi station cold heading machine are bolts, screws and nuts.
Is cold heading and cold extrusion the same thing?
Cold pier and cold extrusion are basically deformation processing under the same conditions, but the operation mode is different. Cold pier belongs to the forging deformation of small workpieces and is often used in fastener industry. Cold extrusion belongs to the extrusion deformation of larger workpieces, which is widely used; Cold heading is equivalent to a branch of cold extrusion. In the process of making bolts, hexagonal head forming belongs to cold heading and rod diameter reduction belongs to cold extrusion (forward extrusion). The non chamfered hexagon flange bolt (multi station forming) has both cold heading and cold extrusion. The front shaping of hexagon nut is only cold heading, and the hole extrusion in the later process is cold extrusion (positive and negative extrusion).
The cold upsetting die bears severe stamping load in the process of cold upsetting, and its concave die surface bears high compressive stress, which requires the die material to have high strength, toughness and wear resistance.
