China Factory Suppliers of Carbon Steel and Stainless Steel Flanges for Pipe Connections - Leak-Proof Solutions
Common Flange Types
| Flange Type | Description | Typical Applications |
|---|---|---|
| Weld Neck Flange (WN) | Features a long tapered hub that provides reinforcement; butt-welded to pipe | High-pressure, high-temperature services; critical applications requiring high integrity |
| Slip-On Flange (SO) | Slides over pipe and welded both inside and outside; lower installation cost | Low to medium pressure applications; general piping systems |
| Blind Flange (BL) | Solid flange with no bore; used to close pipe ends, valves, or pressure vessel openings | Pipeline termination; pressure testing; future expansion points |
| Threaded Flange (THDF) | Bore with threads; screws onto threaded pipe without welding | Low-pressure utility services; areas where welding is hazardous |
| Socket Weld Flange (SW) | Bore with socket counterbore; pipe inserted and fillet welded | Small diameter, high-pressure lines; typically ½" to 4" NPS |
| Lap Joint Flange (LJ) | Two-part assembly with stub end and backing flange; flange rotates freely | Systems requiring frequent dismantling; corrosive services with expensive materials |
Flange Facing Types
| Face Type | Description | Typical Gasket |
|---|---|---|
| Raised Face (RF) | Sealing surface raised above bolt circle; most common facing | Soft or semi-metallic gaskets |
| Flat Face (FF) | Sealing surface flush with bolt circle | Full-face non-metallic gaskets |
| Ring-Type Joint (RTJ) | Groove machined into face for metal ring gasket | Oval or octagonal metal ring gaskets |
Standard
| Material Type | Standard | Common Grades |
|---|---|---|
| Carbon Steel | ASTM A105 | Standard specification for forged carbon steel piping components |
| Carbon Steel (Low Temp) | ASTM A350 | For low-temperature service; common grade LF2 |
| Stainless Steel | ASTM A182 | Forged stainless steel; common grades F304, F304L, F316, F316L |
| Alloy Steel | ASTM A182 | Chrome-moly grades for high-temperature; F11, F22 |
Wall Thickness Schedules
Frequently Asked Questions (FAQ)
What are the typical applications for a Weld Neck Flange (WN)?
Weld Neck Flanges are typically used in high-pressure and high-temperature services, as well as in critical applications requiring high integrity.
Which flange type is recommended for systems requiring frequent dismantling?
The Lap Joint Flange (LJ) is ideal for systems requiring frequent dismantling and is also commonly used in corrosive services with expensive materials.
What is the most common flange facing type?
The Raised Face (RF) is the most common flange facing type. It features a sealing surface raised above the bolt circle and typically uses soft or semi-metallic gaskets.
What material standard is used for forged carbon steel flanges?
ASTM A105 is the standard specification utilized for forged carbon steel piping components.
What kind of gasket is used with a Ring-Type Joint (RTJ) face?
Oval or octagonal metal ring gaskets are specifically designed to be used with a Ring-Type Joint (RTJ) face.
Can threaded flanges be installed without welding?
Yes, a Threaded Flange (THDF) has a bore with threads that screws directly onto a threaded pipe, making it ideal for low-pressure utility services or areas where welding is hazardous.