A flange is a mechanical component used to connect pipes, valves, pumps, and other equipment in a piping system. It allows for easy assembly, disassembly, and maintenance by bolting components together and typically includes a gasket for sealing.
🔧 What Is a Flange?
A flange is a disc-shaped part that creates a strong and sealed connection between pipe sections or between pipes and equipment. It usually has bolt holes and a raised face or groove for gasket placement to ensure leak-proof joints.
🧱 Types of Flanges
| Flange Type | Description |
|---|---|
| Weld Neck | Long tapered hub, welded to pipe; used in high-pressure/high-temp systems. |
| Slip-On | Slides over pipe and is welded; easier to align and install. |
| Socket Weld | Pipe fits into a socket and is fillet welded; for small-diameter pipes. |
| Lap Joint | Used with stub ends; suitable for systems requiring frequent dismantling. |
| Threaded | Screwed onto pipe with threads; used in low-pressure systems. |
| Blind | Solid disc to close pipe ends or nozzles; allows pressure testing. |
| Long Weld Neck | Extended hub for specialized connections, often in vessels or tanks. |
| Orifice | Used with flow meters, includes orifice plate for measuring flow. |
📏 Common Flange Standards
| Standard | Region/Body | Description |
|---|---|---|
| ASME B16.5 | USA (ASME) | Flanges from ½" to 24" for pressure ratings up to Class 2500 |
| ASME B16.47 | USA (ASME) | Large-diameter flanges from 26" to 60" |
| DIN | Germany | Metric-based flanges (e.g., DIN 2633, DIN 2501) |
| EN 1092-1 | Europe (CEN) | Unified European flange standard |
| JIS B2220 | Japan | Japanese Industrial Standard flanges |
| AWWA C207 | USA (Water Works) | Flanges for water service pipelines |
| BS 4504 | UK (British) | British Standard metric flanges |
🛠️ Applications of Flanges
Oil & Gas Pipelines
Petrochemical Plants
Power Generation
Water Treatment
Pharmaceutical and Food Processing
HVAC Systems
Shipbuilding and Marine Systems
✅ Advantages of Using Flanges
Easy assembly and disassembly
Allows inspection and cleaning
Accommodates thermal expansion and mechanical stress
Facilitates alignment and maintenance
