Gear Manufacturing Process & Machine Compression

There are two kinds of gear manufacturing process, forging and casting. 

Forged gears are generally parts made by heating steel to austenite, then applying pressure with a die, and forge it with external force. Castings have defects such as segregation, shrinkage and looseness. Taking gear forgings as an example, the fluidity of the metal is retained after the steel passes through the forging, which can significantly improve the mechanical properties of metal materials.

Differences of gear manufacturing process

• Firstly, the mechanical properties are different. After the secondary processing of the forging, there will be a hardening process. This process will cause the arrangement to be fine and the mechanical properties are non-directional, which is better than the casting.
• Second, the difference in gear forming process methods. Casting process for gear is melted in the melting furnace, and then poured into the model, and then cooled. The gear forging process is repeatedly formed by the forging press under the effect of pressure.
• Gear casting: It is composed of direct casting of molten steel, the grain size is poor, the metal density is slightly low, and the mechanical properties are not stable.\
• Gear forgings: After casting, it is formed by high temperature forging, with fine grain size, slightly higher density, and stable mechanical properties.
• Investigation from the non-machined appearance: The castings are small grains, and the seams (casting molds and lids) can be seen; free forging, the appearance is black after casting, the appearance is called flakes, and the casting folds can be seen. Closed die forging, at first glance, is somewhat similar to castings, but the graininess of the appearance is still delicate and contrasting. And forging is often done in small pieces, large parts are difficult to do.
• Investigation from the machining surface: Cast iron is significantly different from forgings, the appearance of cast iron is not shiny (it will still be shiny after grinding), chippings are chip breaking, and gray cast iron will have powdery chips. The cast steel working surface and the forging processing surface do not think there is a significant difference between them, and both have gloss.
• Gear forgings do not have forming defects such as shrinkage, so mechanical properties are better than castings. The strength of castings is the ease of production and molding. Fine-scaled mechanical properties are not required, and can be molded at one time. Mainly for the differences in molding methods.

Conclusion

From the appearance of the two gear manufacturing process, we can see that the surface of the casting is thick, and there is segregation and shrinkage. But the surface of the gear forging is smooth and shiny, because the gear forging is forged by external force, the casting is solidified.

Ideal Gear Manufacturing Machine Choose

From the introduction above, we can know that forging is better than casting in the gear manufacturing process. So what is the best gear manufacturing machine?

The most used gear manufacturing machine in the past is closed die hot forging hammer, in recent years, the electric screw forging press, as a new type of forging press, is more and more used in gear manufacturing. As it has more advantages than forging hammer.

For general gear, as the meshing teeth are small, the blank is hard to fill the die, so no matter in forging hammer or electric screw forging press, gear ring is forged firstly, and then machining the meshing teeth. However, for some special gear like basin gear forging, as the speed of electric screw forging press is slower than forging hammer, the metal blank can flow slowly and fill the mold, so the electric screw forging press forge the final shape directly, but a forging hammer is hard to shape the meshing teeth as mentioned above. 

Thus, since the birth of electric screw forging press, there have been many gear forging manufacturers using electric screw press instead of forging hammer. What’s more, paired with robot and other forging assistant machine, the electric screw forging press can accomplish forging automation. Anyang Forging Press can provide electric screw forging press from 250 ton to 4000 ton.

Forging larger gear, ring rolling machine is the best choice. Make the gear blank firstly, then machine the final shape. We can also manufacture both vertical and vertical ring rolling machine.

Forging automation turn-key solution is also available. If you are interested in our gear manufacturing machine, please feel free to contact us!