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Things You Need To Know About Threaded Flanges

In the intricate world of pipes, valves, and fittings, flanges often play a crucial yet overlooked role. These small yet functional components do wonders in many industrial processes. They provide robust and leakage-free pipe connections.

One such flange is a threaded flange, useful in numerous industries like oil and gas, chemicals, and food. If you want to learn more about it, you’ve landed on the right page. We have explained everything about thread flanges.

Let’s get started!
Threaded Flanges

What is Threaded Flange?

A threaded flange connects a device securely to a pipe without the requirement of welding. It entirely relies on threads to create an unbreakable and leakage-free connection between the flange and the pipe. They are also called screw flanges, a type of pipe flange with internal threads.

There are mainly two threads: male and female thread. The pipe’s end has a male thread, and the flange’s bore has a female thread. The male-threaded pipe then screws into the female-threaded flange.

The Anatomy of a Threaded Flanges

Let’s look into the different parts of a threaded flange for a better understanding of its functionality. A typical threaded flange consists of:

Threaded Bore: The inner surface with internal threads that attach to the pipe.

Flange Face: The flat surface where the sealing takes place.

Bolt Holes: Holes around the circumference for securing the flange with bolts.

Raised Face: A raised portion around the flange face that improves the sealing capability.

Advantages of Threaded Flanges

Accessibility for Maintenance: Threaded connections are easy to disassemble, making maintenance and repair more straightforward. This accessibility is especially valuable in systems where components may need frequent inspection or replacement.

Cost-Effective: Threaded flanges are often more budget-friendly than flange types requiring welding. Since they eliminate the need for welding labor and equipment, they can lead to cost savings in material and labor expenses.

No Heat-Affected Zone (HAZ): Unlike welded connections that create a heat-affected zone (HAZ), threaded connections do not introduce heat into the pipe material.

Reduced Risk of Welding Defects: Welding can introduce defects such as porosity, cracks, or incomplete penetration.

Leak Resistance: When properly sealed with thread sealant or tape, threaded flanges provide a strong, leak-resistant connection and prevent fluid or gas from escaping.

Reduced Fire Hazard: In applications where fire safety is a concern, threaded flanges can be advantageous.

Since they do not require welding, there is no risk of sparks or flames during installation or maintenance, reducing the fire hazard.

Pressure and Temperature Compatibility:

Threaded flanges are suitable for various pressure and temperature conditions, depending on the material utilized. The adaptive nature of these flanges makes them an ideal choice for different industries.

Ease of Alignment: Threaded connections are best when it comes to alignment. The threads act as a guide for the pipe to achieve the proper fit.

Versatility in Material Choices:  Threaded flanges come in many materials, including stainless steel, carbon steel, brass, and more. It allows industries to choose the thread flanges’ material per their specific project requirement -for instance, corrosion resistance or temperature tolerance.

Materials and Sizes of Threaded Flanges

Are you looking for specific materials and dimensions of thread flanges? Well, thread flanges are available in numerous materials. It can include stainless steel, carbon steel, brass, and more.

In addition, thread flanges are generally available in sizes between 1/2 inch to 24 inches or more. Choosing the right size and material for a secure connection without any leakage is crucial.

Installation Guidelines

Here’s a step-by-step guide for threaded flanges installation:

Prepare the Pipe: Ensure the pipe end is clean and free from burrs or imperfections.

Apply Thread Sealant: Use a thread sealant or tape on the external threads of the pipe.

It helps create a tight seal.

Align Flange and Pipe: Carefully align the flange with the pipe and start threading them together.

Hand Tightens: The hand tightens the flange until it’s snug against the pipe.

Torque Bolts: Use a torque wrench to tighten the bolts evenly, following the manufacturer’s specifications.

Check for Leaks: Conduct a pressure test after installation to ensure no leaks.

Industrial Application

Threaded flanges find application in various industries, including:

Plumbing: Used in residential and commercial plumbing systems for connecting pipes, valves, and fixtures.

Chemical Industry: Suitable for connecting pipes carrying chemicals due to their corrosion resistance.

Oil and Gas: Threaded flanges are helpful in pipelines for transporting oil and gas.

Water Treatment: Commonly used in water treatment plants for connecting pipes and equipment.

Maintenance and Troubleshooting

Proper maintenance ensures the longevity of threaded flanges. Regularly inspect the flanges for signs of wear, corrosion, or leaks. If you notice any issues, follow these troubleshooting steps:

Leakage: Check the sealant or tape for damage and reapply if necessary.

Corrosion: If corrosion occurs, replace the flange with a corrosion-resistant material.

Thread Damage: If the threads are damaged, replace the flange and ensure proper thread alignment during installation.

Safety Precautions

When working with threaded flanges, safety should be a top priority:

(a)Always wear appropriate personal protective equipment (PPE).

(b)Be cautious of hot fluids or surfaces.

© Ensure the work area is well-ventilated, especially when dealing with chemicals.


Threaded flanges may be a small component, but their role in the piping fitting system is enormous. From ease of installation to versatility in various industries, threaded flanges deserve recognition for their essential role in keeping things flowing smoothly. The above-given information can help you choose the right material dimension for your specific project needs.

If you have any suspicions regarding flanges, contact Texas Flange!


Q.1 What is a threaded flange, and how does it work?

Answer: A threaded flange is a type of pipe flange with internal threads that can easily be attached to pipes, valves, or fittings with matching external threads. It creates a strong, leak-free connection when the male-threaded pipe screws into the female-threaded flange.

Q.2 Can threaded flanges be used for both liquids and gases?

Answer: Threaded flanges are appropriate for both liquids and gases.

However, selecting the appropriate material and ensuring a proper seal with thread sealant or tape to prevent leaks is essential.

Q.3 What is the difference between threaded flanges and slip-on flanges?

Answer: Threaded flanges have internal threads and are screwed onto pipes, while slip-on flanges have a smooth, non-threaded bore to slide over the pipe. Threaded flanges require no welding, whereas slip-on flanges need welding.


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1 month ago

Threaded flanges seem like a practical solution for industries requiring robust and leak-resistant connections without welding hassles.

1 month ago

I appreciate the detailed breakdown of the anatomy and advantages of threaded flanges. It makes their importance in industrial processes clearer.

1 month ago

What are the advantages of using threaded flanges over welded connections? 

1 month ago
Reply to  Roger

Threaded flanges offer advantages such as easier maintenance, cost-effectiveness, absence of heat-affected zones, reduced risk of welding defects, leak resistance, and reduced fire hazard.

1 month ago

What industries commonly utilize threaded flanges, and what are their available sizes and materials? 

1 month ago
Reply to  Edmond

Threaded flanges find application in plumbing, chemical, oil and gas, and water treatment industries. They are available in sizes ranging from 1/2 inch to 24 inches or more and can be made from materials like stainless steel, carbon steel, and brass, among others.

1 month ago

The installation guidelines provided for threaded flanges appear straightforward and could be beneficial for ensuring a secure connection.