Cold heading machine is a kind of special equipment mainly used to manufacture nuts, bolts and other fasteners in batches. Most are heavy equipment that puts pressure on metal, and most are equipped with safety guards to keep equipment and people safe. The chemical composition and mechanical properties of the cold heading raw materials of the cold pier machine should meet the relevant standards of the multi-station automatic cold heading machine. Common raw materials include copper aluminum alloy, carbon steel, stainless steel and other materials. The following introduces the selection of raw materials for the cold heading machine;

1. Selection of raw materials for cold heading machine workpieces

(1) The raw material must be spheroidized and annealed, and its metallographic structure is spherical pearlite.

(2) In order to reduce the cracking tendency of the material as much as possible and prolong the service life of the mold, the raw material is also required to have as low a hardness as possible to improve the plasticity.

(3) The inch accuracy of raw materials should generally be determined according to the specific requirements and process conditions of the workpiece. Generally speaking, multi-station cold heading machines have lower requirements on the dimensional accuracy of diameter reduction and strong shrinkage.

(4) The surface quality of raw materials requires that the lubricating film is dull and dull, and the surface must not have scratches, wrinkles, cracks, abrasions, rust, oxide skin, pits and other defects.

(5) The cold heading machine requires that the total thickness of the radial decarburization layer of the raw material does not exceed 1% of the diameter of the raw material.

(6) In order to ensure the cutting quality when the surface of the raw material is formed by cold requirements, it is hard and the core is soft.

(7) The raw materials should be subjected to cold heading test, and cold work hardening will increase the resistance to deformation. The lower the sensitivity of the material to cold work hardening, the better.

2. Selection of forming oil for cold heading machine

(1) It has excellent extreme pressure lubrication performance, high temperature resistance, extreme pressure wear resistance, rust prevention and high temperature oxidation resistance and stability. Improve the precision and flatness of the processed parts, can prevent mold sintering, meet the multi-station forming processing of standard parts and non-standard parts, and can be fully qualified for cold heading stainless steel parts.

(2) The oil fume and "floating mist" can be minimized, and the nut process of the forced shrinkage mold can be satisfied.

(3) It has good performance for workpieces with large deformation, such as hollow, high-strength bolts, sleeves, stainless steel hollow, semi-hollow rivets, etc.

(4) It can effectively protect the punch (punch needle) and die and prolong the service life.

(5) The heat dissipation effect is good, which prevents the local temperature of the workpiece and the mold from being too high during the cold forming process.

(6) It has good high temperature resistance and is not easy to produce sludge. Low odor, low smoke, protect the operating environment.

(7) The forming oil of the cold heading machine has a certain anti-rust performance, which can meet the anti-rust requirements between the processes.

(8) It can meet the forming process of large deformation cold heading stainless steel and carbon steel with high requirements.

The above is the selection method of raw materials for cold heading machine process. The use of raw materials that meet the process requirements can effectively avoid the quality problems of the workpiece.