Free forging has low productivity and large machining allowance, but the tools are simple and universal, so it is widely used to forge forgings with simple shape and small batch production. Free forging equipment includes air hammer, steam-air hammer and hydraulic press, which are suitable for producing small, medium and large forgings respectively. Die forging has high productivity, simple operation and easy mechanization and automation. Die forgings have high dimensional accuracy, small machining allowance and more reasonable fiber structure distribution, which can further improve the service life of parts.
First, the basic process of free forging: In free forging, the shape of forgings is gradually forged through some basic deformation processes. The basic process of free forging includes upsetting, drawing, stamping, bending and cutting.
1. Upsetting is the operation process of forging the original blank along the axial direction to reduce its height and increase its cross section. This process is often used to forge gear blanks and other disc forgings. Upsetting can be divided into whole upsetting and local upsetting.
2. Drawing is a forging process, which increases the length of the blank and reduces the cross section. It is usually used to produce shaft blanks, such as lathe spindles and connecting rods.
3. Forging process of punching a through hole or a non-through hole on the blank with a punch.
4. Forging process of bending the blank into a certain angle or shape.
5. The twisted forging process makes one part of the blank rotate at a certain angle relative to another part.
6. Forging process of cutting and dividing the blank or cutting off the material head.
Second, die forging
Die forging is called die forging, which is to put the heated blank into a forging die fixed on die forging equipment for forming.
1. Basic working procedures of die forging: blanking, heating, pre-forging, final forging, stamping, trimming, tempering and shot peening. Common processes include upsetting, drawing, bending, stamping and forming.
2. Common die forging equipment Common die forging equipment includes die forging hammer, hot die forging press, flat forging press and friction press.
Generally speaking, forged flanges are of good quality, generally produced by die forging, with fine crystal structure, high strength and, of course, high price.
Casting flange and forging flange are common flange manufacturing methods. According to the strength requirements of the parts used, if the requirements are not high, you can also choose to turn the flange.
Third, cut the flange.
Directly cut the disc with flange inside, outside and thickness on the middle plate, and then process the bolt hole and waterline. Flanges produced in this way are called cutting flanges, and the maximum diameter of such flanges is limited to the width of the middle plate.
Four, rolling flange
The process of cutting strips with medium plate and then rolling them into a circle is called rolling, which is mostly used in the production of some large flanges. After successful winding, weld, then flatten, and then process waterline and bolt hole.