Structural Features:
A flange with a threaded bore, allowing connection to the pipe without welding.
Ideal for low-pressure and non-cyclic applications where welding is not feasible.
Threads are typically NPT (National Pipe Thread) or BSP for compatibility.
Common flange faces: RF / FF
Welding Method:
No welding required.
The flange screws directly onto the external thread of the pipe.
Can also be seal welded around the joint for added leak protection if necessary.
Applications:
Low-pressure piping systems, flammable or explosive environments where welding is hazardous.
Used in:
-Oil & Gas
-Chemical Processing
-Water Supply Systems
-Firefighting Networks
-Steam and Air Lines
Common Size Standards:
ASME B16.5: 1/2” – 24”
(Note: Threaded flanges are not typically used above 4” in size due to structural concerns.)
Pressure Ratings:
150#, 300#, 600#
(Seldom used above 600# as threading weakens the flange neck.)
Flange Face Types:
RF (Raised Face)
FF (Flat Face)
Materials:
Carbon Steel, Stainless Steel, Galvanized Steel, Alloy Steel, Bronze
Recommendation:
Threaded flanges are an excellent choice when welding is impractical or dangerous.
Best suited for small-diameter, low-pressure systems.
A cost-effective and maintenance-friendly option in hazardous or flammable areas.
