Analysis of cold heading forming oil and oil selection requirements!
April 06, 2022
The cold heading forging process is a processing method that utilizes the plastic deformation of the metal under the action of external force, and redistributes and transfers the metal volume with the help of a die, thereby forming the required parts or blanks. The cold heading process can improve the material rate. It is a pressure working method based on plastic deformation, which can realize less or no cutting. The general material utilization rate is above 85%, and the highest can reach above 99%. The time and process of deformation of metal products are relatively short, especially processing parts on a multi-station forming machine, which can greatly improve productivity.
For multi-station forming and high-speed processing of difficult-to-machine materials such as stainless steel, high-strength steel, and alloy steel, such as stainless steel screw head forming, cold heading, warm heading stainless steel nuts, bolts, high-strength bolts, stainless steel hollow, semi-hollow rivets, etc., ordinary The mechanical oil is not suitable, which will cause the mold to wear quickly and scratches on the surface of the workpiece. Therefore, it is necessary to use cold heading oil with high extreme pressure performance in cold heading forming of difficult-to-machine materials such as stainless steel.
Cold heading oil should have the following characteristics: 1) Reduce friction, lubricate and cool the processed metal and mold, thereby reducing power consumption; 2) Reduce mold wear and extend the service life of the mold; 3) Improve the quality and precision of the machined metal surface and improve the finish; 4) Control the temperature, control the temperature gradient caused by the heat loss of the workpiece during processing to reduce the processing deformation, and play the role of heat dissipation and heat insulation to prevent the workpiece from quenching and the thermal shock of the mold; 5) Protect the processed metal surface from oxidation or embroidery. There will be no workpiece pulling phenomenon. Selection method of cold heading oil: Cold heading oil plays a key role in the fastener manufacturing process. Good cooling performance and extreme pressure and anti-wear performance have made a qualitative leap in the service life of the punch and the accuracy of the workpiece. Depending on the material of the workpiece, the focus of the performance of cold heading forming oil is also different.
(1) When selecting cold heading oil for carbon steel, the best viscosity should be determined according to the difficulty of the process. It is also necessary to pay attention to the rust of the machine and workpiece caused by the chlorine type cold heading oil. Molding oil can effectively avoid rust problems.
(2) Stainless steel is a material that is prone to hardening, and it is required to use cold heading forming oil with high oil film strength and excellent extreme pressure and anti-wear properties. Generally, oil products containing sulfur and chlorine compound additives are used to ensure the extreme pressure performance while avoiding the blackening of the workpiece and the breakage of the punch. Unisun stainless steel cold heading oil contains a large number of anti-wear and anti-sintering additives, which can significantly extend the life of the mold.
