What are the Main Production Processes of Flanges?

The production process of flange is mainly divided into four kinds: forging, casting, cutting and rolling.

(1) Casting Flanges and Forged Flanges

Casting flange, the shape and size of the blank is accurate, small processing volume, low cost, but there are casting defects (porosity. Crack. Inclusions); casting internal organization is poor streamline (if the cutting parts, streamline worse).

Forging flange is generally lower than the casting flange carbon is not easy to rust, forging streamline good, dense organization, mechanical properties better than casting flange; forging process is not appropriate will also appear grain size or uneven, hardening cracking phenomenon, forging cost is higher than casting flange; forging than casting can withstand higher shear and tensile forces.

Castings have the advantage of being able to create a more complex shape, the cost is relatively low; forgings have the advantage of uniform internal organization, there is no casting in the porosity, inclusions and other harmful defects.

The forging process generally consists of the following processes, i.e. selecting good billets for discharging, heating, forming, and cooling after forging. The forging process methods are free forging, die forging and tire film forging. When producing, according to the size of the forging quality, the number of production batch to choose different forging methods.

Free forging productivity is low, processing allowance is large, but the tool is simple, versatility, so it is widely used to forge the shape of a simple single piece, small batch production of forgings. Free forging equipment includes air hammer, steam-air hammer and hydraulic press, which are suitable for the production of small, medium and large forgings respectively. Die forging productivity is high, simple operation, easy to achieve mechanization and automation. Die forging parts have high dimensional accuracy, small machining allowance and more reasonable fiber tissue distribution of forgings, which can further improve the service life of the parts.

The basic process of free forging: In free forging, the shape of forgings is gradually forged into the billet through some basic deformation processes. The basic processes of free forging are upsetting, drawing, punching, bending and cutting, etc.

1. Heading is the process of forging the original billet in the axial direction to reduce its height and make it larger in cross section. This process is often used to forge gear billets and other disc-shaped forgings. Roughing is divided into two types: full roughing and partial roughing.

2. Drawing is a forging process that increases the length and decreases the cross-section of a billet, and is usually used to produce shaft blanks such as lathe spindles and connecting rods.

3. Punching is the forging process of punching out through holes or not through holes in the billet.

4. Bending is a forging process to bend the billet into a certain angle or shape.

5. Twisting is a forging process in which one part of a billet is rotated at an angle with respect to another part.

6. The forging process of cutting and dividing the billet or removing the head.

Die forging is called model forging, in which the heated billet is placed in a forging die fixed on the die forging equipment and forged into shape.

1. The basic process of die forging die forging process: under the material, heating, pre-forging, final forging, punching even skin, cutting edge, tempering, shot peening. Commonly used processes are upsetting, drawing length, bending, punching, forming.

2. Commonly used die forging equipment commonly used die forging equipment are die forging hammer, hot die forging press, flat forging machine and friction press, etc..

Generally speaking, forging flange quality is better, generally through die forging production, crystal organization is fine, high strength, of course, the price is also more expensive.

Whether casting flange or forging flange are flange common manufacturing methods, depending on the strength requirements of the parts to be used, if the requirements are not high, you can also choose to turn the system flange.

(2) Cut Flange

In the plate directly cut out the flange of the inner and outer diameter and thickness of the disk with the amount of processing, and then the bolt hole and water line processing. The flange produced in this way is called cut flange, the large diameter of such flanges to the width of the plate as the limit.

(3) Rolled Flange

Cut strips with the plate and then rolled into a round process is called rolling, mostly used in the production of some large flange. After the successful rolling system for welding, and then flattening, and then the waterline and bolt hole process.