Forged Flanges VS Cast Flanges

Oct. 26, 2021

Cast Flange

Flanges can either be forged or cast. Both manufacturing methods have their advantages and disadvantages, depending on the application you have in mind for your flange. Below, we will delve into the advantages and disadvantages of both forged steel flanges and cast iron flanges.



Casting is the process in which the metal is heated until molten then poured into a mold or vessel to create the desired shape. They are often used in cases that are too large, complicated, or other wise not suitable for forgings. Some of the advantages of flanges manufactured in this way include lower costs of production, the ability to make more intricate parts at lower costs, as well as having no true upper limit on size when it comes to your part.

There are, however, some drawbacks to cast iron flanges. The most important of these being how susceptible they are to internal defects. Due to this, cast flanges are not suitable for high pressure applications or applications in which the probability of corrosion is high. Despite advancement of casting technology and computer optimization of the casting process and designs, it is still difficult to meet the standards required for petrochemical industry applications.



Forging is the application of mechanical and thermal energy to steel billets or ingots to cause material to change its shape while still in solid form. Forgings offer consistency in composition and structure.  Due to the nature of the production of forged flanges, the production costs are higher than that of cast flanges. Though they cannot have the complex shapes that cast flanges can be made in, their internal structure is more compact and therefore seldom have the defects the often affect cast flanges. Forging eliminates defects found in casting such as shrinkage, porosity, cavities, or cold pour issues.


Tips:What are the flanges?

Flanges are an integral part of the Piping industry. These Flanges are used to form a link between two different Pipes. Flat (FF), elevated (RF), ring joint (RTJ), lap joint (M&F), tongue, and groove (T&G) are the 6 styles of flange faces needed. Multi-faced flanges need different gaskets and should never be matted to avoid joint leakage. The flanges RF and FF may have various finishing forms (i.e. roughness at the top of the surface): flat, lined, and serrated. Although flanges themselves have specific pound scores that reflect the levels of pressure and temperature to which they can operate, the individual flange faces vary depending on the context within which they are to be used.

Various types of flange faces are used to seat the sealing gasket content as the contact surfaces. The faces are panels which matt with flanges, funnels or valves. Flange faces must be smooth enough to ensure that the flanges are fastened together to maintain a stable, leak-free seal.

We are an OEM cast iron flange supplier, please feel free to contact us if you need them.