Generally, the process of flange forging consists of the following steps: billet cutting, heating, forming, and cooling. The forging process includes free forging, die forging and fetal membrane forging.
Production, according to the size of the forging quality, the number of production batch to choose a different forging method：
- Free flange forging
Free forging has low productivity, large machining allowance, but the tool is simple.universal, so it is widely used in forging simple shape of the single piece, small batch production of forging. Free forging equipment has air hammer, steam – air hammer and hydraulic press,.respectively suitable for small, medium and large forging production. Die forging high productivity, simple operation, easy to realize mechanization and automation. The die forgings have high dimensional accuracy. small machining allowance and reasonable fiber structure distribution, which can further improve the service life of parts.
The basic process of free forging:
free forging, the shape of the forging is through some basic deformation processes to gradually forge the blank. The basic processes of free forging are:
- (1) Upsetting Upsetting is the process of forging the original billet along the axis to reduce its height and increase its cross section. Forge blanks for gears and disc-shaped forgings. There are two types of forging or upsetting: full or local.
- (2) Draw length is to make the length of the billet increase, the forging process to reduce the section, usually used to produce shaft blank, such as lathe spindle, connecting rod, etc.
- (3) the forging process of punching through holes or through holes in the blank.
- (4) bending so that the blank bending angle or shape of the forging process.
- (5) a forging process in which one part of the blank rotates at a fixed angle relative to another.
- (6) the forging process of cutting and dividing the blank or cutting off the material head.
- Die flange forging
The full name of die forging is model forging. The heated billet is placed in the forging die fixed on the die forging equipment.
Die forging process: blanking, heating, pre-forging, final forging, punching even skin, trimming, conditioning, shot peening. Common processes are upsetting, drawing long, bending, punching, forming.
Common die forging equipment includes die forging hammer, hot die forging press, horizontal forging machine and friction press.
Generally speaking, forging flange quality is better, generally through die forging production, crystal organization, high strength, of course, the price is also expensive.
Whether casting flange or forging flange are common flange manufacturing methods, see the need to use the strength of the components required, if the requirements are not high, you can also choose turning flange system.
- Cut flange
In the middle plate directly cut out the flange left inside and outside diameter and thickness of the disk, and then the bolt hole and water line processing. The flanges produced in this way are called cut flanges, which are large in diameter to the width of the plate.
- Rolled flange
With the plate cut and then rolled into a round process called rolling, used for some large flange production. After the success of the rolling welding, and then flattening, then water line and bolt hole processing technology.