Casting flange
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Both cast flanges and forged flanges are common manufacturing methods for flanges. Forged flanges are produced on the basis of cast steel flanges and are much stronger than cast steel flanges. As for whether to use a cast flange or a forged flange, it depends on the strength requirements of the components to be used. According to the flange material: stainless steel flange, carbon steel flange, alloy steel flange by type are: plate flat welding flange, with neck flat welding flange, butt welding flange, blind flange flange cover, loose cover Flange, threaded flange, socket welding flange, etc.
Cast flanges can produce relatively complex shapes with relatively low cost; general integral flanges (such as valves) are cast. The cast flange has a precise shape and size of the blank, a small amount of processing, a poor streamlined internal structure of the cast flange, and a casting defect (crack, sand hole, air hole, inclusion).
Forging Flange
Forgings can withstand higher shear and tensile forces than castings. Forged flanges are generally lower in carbon content than cast flanges, are less likely to rust, have better streamlined forgings, are denser in organization, and have better mechanical properties than casting flanges; the advantages of forged flanges are uniform internal organization, and there are no blowholes, inclusions, etc. in the casting. Harmful defects, improper forging process will also appear large or uneven grain, hardening crack phenomenon, the quality of forging flange is better, generally through the production of die forging, fine crystal structure, high strength, forging caused by the higher than the casting flange, the price It is also more expensive than casting flanges.
Forging process is generally under the material, heating, forming, cooling after forging. According to the size of the forging mass, how many production quantities can choose different forging methods. The commonly used forging methods include free forging and die forging.
1. Free forging is widely used to forge single-piece and small batch production forgings with simple shapes. The free forging allowance is large and the productivity is low, but the versatility is high and the tools are simple. The basic process of free forging is to progressively forge a forging blank through some basic deformation processes. The basic processes of free forging include upsetting, pulling, punching, bending and cutting.
2, die forging high productivity, simple operation, easy to implement mechanization and automation. Die forgings have high dimensional accuracy, small machining allowances, and more reasonable distribution of fiber structure for forgings, which can further increase the service life of parts. Die forging is called model forging and the heated billet is forged into a forging die fixed on a die forging apparatus. Common forging equipment includes die forging hammers, hot die forging presses, flat forging presses, and friction presses. The basic processes of die forging: blanking, heating, pre-forging, and final forging. Commonly used processes include upsetting, drawing, bending, punching and forming.