Flanges
We supply a comprehensive range of industrial forged flanges connected to pipes, valves, and pumps to create a piping system. Manufactured to ASME B16.5, B16.47, and API 6A standards, our flanges ensure leak-proof connections in the most demanding environments.
Weld Neck Flanges (WN)
Designed for high-pressure and critical applications. The long tapered hub is butt-welded to the pipe, providing structural reinforcement and a smooth transition for fluid flow, minimizing turbulence and erosion.
| Connection | Buttweld to pipe end |
|---|---|
| Pressure | Class 150# to 2500# |
| Faces | Raised Face (RF), Ring Type Joint (RTJ), Flat Face (FF) |
| Best For | High pressure, severe service conditions |
Slip-On Flanges (SO)
A popular and economical choice. The flange "slips over" the pipe and is fillet welded on both the inside and outside. Easier to align than weld necks but has slightly lower pressure integrity.
| Connection | Double Fillet Weld (Inside & Outside) |
|---|---|
| Pressure | Class 150# to 1500# |
| Faces | Raised Face (RF), Flat Face (FF) |
| Best For | Low to medium pressure systems |
Blind Flanges (BL)
A solid disk flange used to seal the end of a piping system or a pressure vessel opening. They must withstand high mechanical stress from internal pressure and bolting forces.
| Function | Closing/Sealing pipe ends |
|---|---|
| Pressure | Class 150# to 2500# |
| Faces | Raised Face (RF), RTJ, Flat Face |
| Best For | Pressure testing, future expansion points |
Socket Weld Flanges (SW)
Designed for small-bore, high-pressure piping. The pipe is inserted into a socket bore and fillet welded on the outside only. The internal socket provides smooth flow and good fatigue strength.
| Connection | Single Fillet Weld (Outside) |
|---|---|
| Size Range | Typically 1/2" to 2" (Small Bore) |
| Pressure | Class 150# to 1500# |
| Best For | High pressure, small diameter lines |
Threaded / Screwed Flanges (THD)
Similar to slip-on flanges but the bore is threaded, allowing assembly without welding. Ideal for applications where welding is hazardous or not possible.
| Connection | Threaded (NPT or BSP) |
|---|---|
| Use Case | No welding required environments |
| Limitations | Not for high cyclic loading or very high temps |
| Best For | Utilities, low pressure, hazardous areas |
Lap Joint Flanges (LJF)
Used in conjunction with a Stub End. The flange rotates freely on the pipe, making bolt hole alignment easy. Ideal for systems requiring frequent dismantling for inspection or cleaning.
| Connection | Used with a welded Stub End |
|---|---|
| Feature | Rotates for easy bolt alignment |
| Cost Benefit | Flange material can be lower grade than the pipe |
| Best For | Systems requiring frequent disassembly |
Common Flange Material Grades
| Material Type | Forging Standard & Grade |
|---|---|
| Carbon Steel | ASTM A105 / A105N (Standard Forging) | ASTM A350 LF2 (Low Temp) |
| High Yield Carbon | ASTM A694 F42, F52, F60, F65, F70 (Pipeline Flanges) |
| Stainless Steel | ASTM A182 F304/304L, F316/316L, F321, F347 |
| Alloy Steel | ASTM A182 F1, F5, F9, F11, F22, F91 (High Temp) |
| Duplex Steel | ASTM A182 F51 (UNS S31803), F53/F55 (Super Duplex) |
