Cold heading process is one of the new processes for metal pressure machining with little or no cutting. It is a processing method that makes use of the plastic deformation of metal under the action of external force, and makes the metal volume redistribute and transfer by virtue of the mold, so as to form the required parts or blanks. Cold heading technology is most suitable for producing standard fasteners such as bolts, screws, nuts, rivets, pins, etc.
ADVANTAGES OF FORGING PROCESS
High utilization rate of steel
Cold heading (extrusion) is a kind of machining method with little or no cutting, such as machining hexagon head bolts and hexagon socket head screws with cylindrical head. With the cutting method, the utilization rate of steel is only 25%~35%, while with the cold heading (extrusion) method, the utilization rate can be as high as 85%~95%, which is only some process consumption of the head, tail and cutting hexagon head side.
Using cold extrusion technology to replace cutting to manufacture parts can increase productivity several times, dozens of times, or even hundreds of times. Fasteners (also including some special-shaped parts) suitable for cold heading (extrusion) production are basically symmetrical parts, suitable for high-speed automatic cold heading machine production, and also the main method of mass production.
Parts can obtain ideal surface roughness and dimensional accuracy. The precision of parts can reach IT7~IT8, and the surface roughness can reach R0.2~R0.6. Therefore, the parts processed by cold extrusion are rarely re cut, and only need to be finely ground at the places with high requirements.
The cold work hardening of the metal after cold extrusion and the formation of reasonable fiber streamline distribution in the part make the strength of the part much higher than that of the raw material.
Hot upsetting process
During hot upsetting, the billet is heated to the temperature above the metal recrystallization point by induction heating or in the forging furnace or oven. This extreme high temperature is necessary to avoid strain hardening of metals during deformation.
Generally speaking, complex parts are manufactured by hot upsetting.
Because the metal is in a plastic state, it maintains ductility and toughness and allows material deformation, so it is easier to process
SURFACE TREATMENT PROCESS
Our surface finishes service including: painting, electroplating, powder coating, anodizing, polishing,
black oxide, conversion coating, bead blasting, abrasive blasting.etc