Threaded Flange

What is a threaded flange?

A forged threaded flange（also called companion flanges/screw flanges / NPT flanges/TH flanges） is a type of pipe flange that features internal threads on its bore, allowing it to be directly screwed onto the external threads of a pipe.
This design eliminates the need for welding, making it a convenient choice for pipes that cannot be welded or in situations where welding is not desirable.

Key Features & Applications

Threaded Flanges have a bore with tapered threads and connect to pipes that have external threads. The primary benefit of Threaded Flanges is that no welding is required to attach them.

1. Welding-Free Connection – Perfect for explosive or flammable environments (e.g., petrol stations, chemical plants) where welding sparks pose a risk.
2. Easy Installation & Maintenance – Can be quickly assembled or disassembled compared to welded flanges.
3. Cost-Effective for Small Pipes – Typically used for ½” to 6” pipes, though larger sizes (up to 24”) are available upon request. The amount of additional machining and labor hours that go into producing a larger diameter threaded connection makes them less popular than slip-on flanges or weld neck flanges.
4. Limited to Low-Pressure/Low-Temperature Use – Best suited for non-toxic fluids and moderate conditions, as threads may weaken under high heat or pressure.
5. Face Types – Only available with flat face (FF) or raised face (RF) finishes, not suitable for high-pressure ring-type joints.

Specification:

Standard: ASNI/ASTMB16.5 / 16.36/16.47A/16.47B B2220 – 2001, DIN2527/2636/2637/2638/2566/2576/2633/2635/2642/2653/2655.
Pressure Rate: 150LBS to 2500LBS / PN10 to PN400
Dimension: 1/2″ to 48″
Material: Carbon steel, Alloy Steel, Stainless steel.
Thread type: NP / BSP

Pressure rating:

class 150LBS、300LBS、400LBS、600LBS、900LBS、1500LBS、2500LBS

Dimensions:
ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48, API 605, AWWA AND DRAWING

How to install a threaded flange?

Clean the pipe threads and the inside of the flange to ensure a secure and leak-free connection. Align the threaded flange with the pipe and screw it onto the pipe’s threaded end by hand until it is snug.
Use a wrench to tighten the flange onto the pipe further. Be careful not to over-tighten, as this can damage the threads or pipe. Optionally, use thread sealant or Teflon tape to prevent leaks in lower-pressure systems, ensuring a tight seal.

Click here to know Threaded Flanges Installation Guide 

Choose JS Fittings as your Threaded Flanges Supplier

With 40+ years of experience in steel flange manufacturing, JS Fittings provides:

1. High-quality carbon steel, stainless steel, and alloy threaded flanges
2. Custom sizes and pressure ratings (ASME, ANSI, DIN, and more)
3. Fast delivery & expert technical support

Contact Us for a quote or project consultation—we help you source flanges faster, smarter, and more affordably than competitors!