Raised Face Flange vs Flat Face Flange
Table of Content
- What are Raised Face Flange?
- What are Flat Face Flange?
- Key Differences Between Raised Face Flange vs Flat Face Flange
- Flat Face and Raised Face Flanges: Know the Application Differences
- Raised Face and Flat Face Flange Standard
- RF Flange vs FF Flange Finish
- Selecting the Right Flange Face Types for Your Application?
- Advantages of Raised Face Flange vs Flat Face Flange
Raised Face flanges also called RF flange. RF flange have a raised sealing surface suitable for high pressure like oil & gas. Class 150 raised face flange can both be sealed with flat gasket, SOFT gasket, or semi metallic gasket. Flange with raised face best for high and low temperatures applications. RF facing flange provide better leak prevention in demanding conditions. Raised face pipe flange are common in power plants and petrochemical. The main purpose of raised face flange is to focus more pressure on the small gasket area.
Flat face flanges also called FF flange. Flat face flanges are comparable to the raised face flanges flange, but they do not have the raised area. ASME B16.5 flat face flange suitable for low temperature and pressure applications. The gaskets for Class 150 RF flange are normally made from non metallic materials. Full face gaskets is most common gaskets use for FF flange. Raised face pipe flange are used in less arduous applications such a low pressure water piping. Flat face flange provides a larger contact area for reduces the leakage risk and better sealing.
RF Flange vs FF Flange: Which is Best for Your Project?
Key Differences Between Raised Face Flange vs Flat Face Flange
| Features | Raised Face Flange (RF) | Flat Face Flange (FF) |
| Suitable for | High Pressure | Low Pressure |
| Seal Design | Raised Sealing Face | Sealing Face is Flat |
| Gasket Compatibility | Semi-Metallic and Metallic | Full Face Soft Gaskets |
| Sealing Performance | Reducing leakage risk | Low sealing performance |
| Applications | Petrochemical | Water Pipelines |
| Material | Stainless and Carbon Steel, Alloy Steel | Copper and Cast Iron |
Check Application Wise Difference Between Flat Face and Raised Face Flanges
Flat Face and Raised Face Flanges: Know the Application Differences
| Applications | Flat (FF face) | Raised (RF face) |
| High pressure and temperature applications | No | No |
| Cast iron equipment | Yes | No |
| Industrial valves | Yes | No |
| Chemical plants | No | Yes |
| Petrochemicals applications | No | Yes |
| Low pressure water systems | Yes | No |
Raised Face and Flat Face Flange Standard
| RF Flange Standard | RF Flange Standard |
| ASME B16.5 and ASME B16.47 | ASME B16.47 |
| Raised Face Flange Finish | Flat Face Flange Finish |
| 125-250 RMS | 125-250 RMS |
Selecting the Right Flange Face Types for Your Application?
Advantages of Raised Face Flange vs Flat Face Flange
| Advantages of RF Flange | Advantages of FF Flange |
| Enhanced Sealing | Cost-Effective |
| Pressure Capability | Even Load Distribution |
| Metallic Gasket Use | Equipment Protection |
| Superior Sealing | Easy Alignment |
| Corrosion Resistance | Full-Face Gasket Use |