Custom Flange Manufacturing: A High-Quality Choice to Meet Diverse Needs

In the industrial sector, flanges serve as critical components for connecting piping and equipment; their quality and suitability directly impact the operational efficiency and safety of the entire system. Custom flange manufacturing allows for tailored solutions that meet specific customer requirements and adapt to diverse operating conditions and applications. This article provides a detailed overview of custom flange manufacturing—covering available types, dimensions, machining methods, and materials—to serve as a valuable reference for our customers.

Types of Custom Flanges Available

Plate-Type Slip-On Flanges

The plate-type slip-on flange is a common custom flange variety. It features a simple structure, ease of manufacture, and low cost. These flanges are typically used for piping connections involving low pressure and moderate temperatures—such as in standard water supply and drainage systems. They are available with either flat or raised sealing faces; flat faces suit low-pressure applications with non-toxic media, while raised faces offer superior sealing performance for slightly higher pressure requirements.

Hubbed Slip-On Flanges

Unlike the plate-type version, the hubbed slip-on flange features a short hub. This design enhances the flange's strength and rigidity, enabling it to withstand higher pressures and temperatures. These flanges are frequently used in medium-pressure piping systems within industries such as chemicals and petroleum. They offer various sealing face options—including raised face, tongue-and-groove, and male-and-female—allowing for optimal selection based on the specific medium and operating conditions.

Hubbed Weld-Neck Flanges

Hubbed weld-neck flanges are renowned for their exceptional strength and sealing capabilities. The hub connects to the pipe via a butt-weld, ensuring high weld quality and the ability to withstand the stresses of high pressure and high temperature. These flanges are commonly used in critical piping systems—such as those in the power generation and nuclear energy sectors—that involve high pressures, high temperatures, or flammable and explosive media. Sealing faces typically include raised face or ring-type joint (RTJ) configurations; the RTJ design offers superior sealing performance, making it ideal for high-pressure applications requiring strict sealing integrity.

Socket Weld Flanges

Socket weld flanges are designed for connecting small-diameter piping. The connection involves inserting the pipe into the flange's socket and then welding it in place. The advantages of this type of flange include ease of installation and minimal welding requirements. Socket-weld flanges are commonly used for connecting small-bore piping—such as that for instruments and valves—and find extensive application in precision industrial systems.

Threaded Flanges

Threaded flanges connect to piping via threads, making installation and disassembly relatively convenient. They are suitable for piping connections that do not require frequent dismantling, such as indoor heating or ventilation systems. As their sealing performance is relatively limited, threaded flanges are generally used in low-pressure, ambient-temperature applications.

Custom Flange Dimensions

Standard Size Range

We offer custom flanges in a wide range of standard sizes. We can customize nominal diameters from DN15 to DN2000 and accommodate nominal pressure ratings ranging from 0.25 MPa to 42 MPa. These standard-range custom flanges meet the connection requirements of most industrial piping systems. For instance, standard building water supply and drainage systems typically utilize custom flanges with nominal diameters of DN50–DN200 and pressure ratings of 1.0–1.6 MPa, whereas high-pressure piping systems in the chemical and petroleum industries require flanges with larger diameters and higher pressure ratings.

Special Size Customization

In addition to standard sizes, we offer customization based on specific client requirements. Certain industrial projects may necessitate non-standard flange dimensions; backed by a professional technical team and advanced production equipment, we can manufacture flanges with precision according to detailed dimensional drawings provided by the client. We guarantee quality and accuracy for flanges of all sizes, whether exceptionally large or small. For example, we are capable of meeting client needs for specialized projects requiring extra-large flanges (nominal diameter >DN3000) or ultra-small flanges (nominal diameter <DN10).

Custom Flange Manufacturing Methods

Forging

Forging is a common method for manufacturing custom flanges. It involves applying pressure to a metal billet to induce plastic deformation, thereby achieving the desired shape and dimensions. The forging process improves the metal's internal microstructure, enhancing the flange's strength and toughness. Forging is typically employed for flanges subjected to high pressure and high temperatures, such as weld-neck flanges. The forging process involves stages such as billet heating, forging, and heat treatment. During heating, temperature and duration must be strictly controlled to ensure the metal's properties. For the forging step itself, appropriate equipment and dies are selected based on the flange's shape and dimensions; multiple forging operations are performed to gradually achieve the required form and size. Heat treatment is subsequently applied to relieve internal stresses generated during forging and to enhance the flange's overall performance.

Machining

Machining involves further processing of forged or cast flanges to achieve the required dimensional precision and surface quality. Machining operations include turning, milling, drilling, and boring. Turning is the primary process for machining surfaces such as the outer diameter and inner bore, ensuring dimensional and geometric accuracy. Milling is used for features like sealing faces and bolt holes, improving surface quality and connection precision. Drilling and boring are used for bolt holes and inner bores, requiring high positional and dimensional accuracy.

Materials We Use

Carbon Steel

Carbon steel is a common material for custom flanges. It offers good strength and toughness at a relatively low cost. Carbon steel flanges are suitable for most industrial piping systems, including water supply and drainage, heating, and ventilation. Common carbon steel grades include Q235 and 20# steel. Q235 carbon steel offers good ductility and weldability, making it suitable for general piping connections; 20# steel possesses slightly higher strength and toughness than Q235, making it suitable for applications involving higher pressures and temperatures.

Alloy Steel

Alloy steel is created by adding specific alloying elements—such as chromium, nickel, and molybdenum—to carbon steel. Alloy steel flanges offer superior strength, corrosion resistance, and high-temperature performance. They are frequently used in high-temperature, high-pressure, and corrosive environments within industries such as chemicals, petroleum, and power generation. Common alloy steel grades include 16Mn and 15CrMo. 16Mn alloy steel offers excellent overall performance and is suitable for pipeline connections involving medium pressure and medium temperatures; 15CrMo alloy steel possesses superior high-temperature strength and oxidation resistance, making it ideal for high-temperature, high-pressure piping systems.

Stainless Steel

Stainless steel flanges exhibit outstanding corrosion resistance, allowing them to withstand harsh, corrosive environments. They are commonly used for pipeline connections in industries such as food processing, pharmaceuticals, and chemicals. Common stainless steel grades include 304 and 316L. Grade 304 offers good corrosion resistance and machinability, making it suitable for general corrosive environments; Grade 316L incorporates molybdenum into the 304 alloy, providing enhanced corrosion resistance suitable for highly corrosive environments.

Conclusion

Backed by a professional technical team and advanced production equipment, we provide high-quality, custom-made flange products. Whether meeting standard specifications or unique requirements, we deliver solutions efficiently and accurately. We are committed to supplying premium custom flanges that enhance the operational efficiency and safety of industrial piping systems. By choosing our custom flange manufacturing services, you are assured of receiving excellent products and superior service.