On March 25, 2025, we received a repeat order for DIN 2632 weld neck flanges from a long-standing client in Shanghai. Given our established business relationship, the client placed the order immediately upon receiving the quotation from our sales representative.
Order Information
Product Name: weld neck flange
Flange Face:RF
Dimensions:DN50
Pressure:PN10
Port Thickness:SCH10S
Material:SMO 254
Standard:DIN 2632

The DIN 2632 is a German Institute for Standardization specification that specifically governs the dimensions, materials, and pressure ratings for steel weld neck flanges with a raised face. This standard is widely recognized and respected across Europe and in international projects for its precision and reliability. It defines a range of Pressure Nominal ratings, with PN 10 being a common designation for medium-pressure applications.
A weld neck flange (WNRF) features a long tapered hub that transitions smoothly to the pipe. This structure reduces stress concentration at the base of the flange and provides excellent mechanical strength. PN10 weld neck flanges are particularly used in systems where vibration, high pressure, or high temperature variations occur, as the welded neck ensures a continuous and strong connection.
Compared with slip-on or plate flanges, weld neck flanges offer better fatigue resistance and sealing reliability, which is why they are commonly used in oil, gas, chemical, and power industries.
The term “Raised Face” refers to the sealing surface of the flange. As the name suggests, this type of flange has a raised ring on its face where the gasket is seated. When two raised face flanges are bolted together, the gasket is compressed between these two raised surfaces, creating a tight and effective seal. This design helps to concentrate the bolting pressure on a smaller area, thereby enhancing the sealing capability. All DIN 2632 flanges, including the PN10 weld neck flanges we discuss, typically come with a raised face, making them ideal for a wide array of sealing applications.
SMO254 (UNS S31254) is a super austenitic stainless steel that combines high strength with excellent resistance to pitting, crevice, and chloride stress corrosion. When DIN 2632 PN10 weld neck flanges are made from SMO254, they are particularly suited for seawater systems, desalination plants, and chemical process industries.

| Size | Pipe | Flange | Neck | Raised Face | Drilling | Weight | |||||||||||
| mm | inch | d1 | D | A | T | T-F | K | h1 | h2 | d3 | S | r | F | G | Bolt No | .H | Kg/Pc |
| DN 15 | 1/2“ | 21.3 | 95 | 17.3 | 14 | 12 | 65 | 35 | 6 | 32 | 2.0 | 4 | 2 | 45 | 4 | 14 | 0.66 |
| DN 20 | 3/4″ | 26.9 | 105 | 22.3 | 16 | 14 | 75 | 38 | 6 | 40 | 2.3 | 4 | 2 | 58 | 4 | 14 | 0.96 |
| DN 25 | 1″ | 33.7 | 115 | 28.5 | 16 | 14 | 85 | 38 | 6 | 45 | 2.6 | 4 | 2 | 68 | 4 | 14 | 1.15 |
| DN 32 | 1/4″ | 42.4 | 140 | 37.2 | 16 | 14 | 100 | 40 | 6 | 56 | 2.6 | 6 | 2 | 78 | 4 | 18 | 1.67 |
| DN 40 | 1 1/2″ | 48.3 | 150 | 43.1 | 16 | 13 | 110 | 42 | 7 | 64 | 2.6 | 6 | 3 | 88 | 4 | 18 | 1.85 |
| DN 50 | 2″ | 60.3 | 165 | 54.5 | 18 | 15 | 125 | 45 | 8 | 75 | 2.9 | 6 | 3 | 102 | 4 | 18 | 2.51 |
| DN 65 | 2 1/2″ | 76.1 | 185 | 70.3 | 18 | 15 | 145 | 45 | 10 | 90 | 2.9 | 6 | 3 | 122 | 4 | 18 | 3.06 |
| DN 80 | 3″ | 88.9 | 200 | 82.5 | 20 | 17 | 160 | 50 | 10 | 105 | 3.2 | 8 | 3 | 138 | 8 | 18 | 3.86 |
| DN 100 | 4″ | 114.3 | 220 | 107.1 | 20 | 17 | 180 | 52 | 12 | 131 | 3.6 | 8 | 3 | 158 | 8 | 18 | 4.45 |
| DN 125 | 5″ | 139.7 | 250 | 131.7 | 22 | 19 | 210 | 55 | 12 | 156 | 4.0 | 8 | 3 | 188 | 8 | 18 | 6.12 |
| DN 150 | 6″ | 168.3 | 285 | 159.3 | 22 | 19 | 240 | 55 | 12 | 184 | 4.5 | 10 | 3 | 212 | 8 | 22 | 7.47 |
| DN 200 | 8″ | 219.1 | 340 | 207.3 | 24 | 21 | 295 | 62 | 16 | 235 | 5.9 | 10 | 3 | 268 | 8 | 22 | 11.20 |
| DN 250 | 10″ | 273.0 | 395 | 260.4 | 26 | 23 | 350 | 68 | 16 | 292 | 6.3 | 12 | 3 | 320 | 12 | 22 | 15.05 |
| DN 300 | 12″ | 323.9 | 445 | 309.7 | 26 | 22 | 400 | 68 | 16 | 344 | 7.1 | 12 | 4 | 370 | 12 | 22 | 17.63 |
| DN 350 | 14″ | 355.6 | 505 | 341.4 | 26 | 22 | 460 | 68 | 16 | 385 | 7.1 | 12 | 4 | 430 | 16 | 22 | 23.92 |
| DN 400 | 16″ | 406.4 | 565 | 392.2 | 26 | 22 | 515 | 72 | 16 | 440 | 7.1 | 12 | 4 | 482 | 16 | 26 | 28.98 |
| DN 450 | 18″ | 457.0 | 615 | 442.8 | 28 | 24 | 565 | 72 | 16 | 488 | 7.1 | 12 | 4 | 532 | 20 | 26 | 33.36 |
| DN 500 | 20″ | 508.0 | 670 | 493.8 | 28 | 24 | 620 | 75 | 16 | 542 | 7.1 | 12 | 4 | 585 | 20 | 26 | 38.61 |
| DN 600 | 24″ | 610.0 | 780 | 595.8 | 28 | 23 | 725 | 80 | 18 | 642 | 7.1 | 12 | 5 | 685 | 20 | 30 | 46.97 |
✅Exceptional Resistance to Pitting and Crevice Corrosion
✅High Resistance to Stress Corrosion Cracking
✅Superior Strength and Excellent Ductility
✅Good Weldability and Fabrication Properties
✅Excellent Performance in Acidic and Chloride Environments