What Threaded Flanges Are and How Are They Used

A threaded flange is a device that connects a device that you can secure to a pipe length without the need for welding. With tapered thread, the threaded flange can be tightened onto the pipe without any leakage.

However, a seal weld is commonly used when it is appropriate. The nature of the threaded connection makes the threaded flange one of the viable options when welding is not feasible, like in explosives or highly flammable areas. The flange is commonly used only on small-diameter pipes.

threaded flange

In most refineries, manufacturing shipyards, and facilities, the highly explosive nature of the materials moved through the pipeline prohibits welding. A threaded flange is a good option in this environment when you assemble pipelines.

Using a tapered thread inside the flange, the pipe is tapered on the exterior and is threaded into the threaded flange. The flange joint becomes leak-proof and tight as the two tapers become enmeshed.

If the conditions exist that dem to be safe welding, a seal weld is occasionally placed around the junction of the flange and pipe.

Sometimes a seal weld is useful in talking about threaded connections. The special flange is usually used for the high-pressure piping system with smaller diameter applications. The larger the flange is, the harder the ability to machine a thread.


A threaded flange means the inner bore of the flange is a thread, the shape of the threaded flange is like the slip-on flange, so the threaded flange could be plate shape or with a hub for the longer threads.


The threaded pipe flange comes with a pipe connected to a pipe with an external thread on the end of the pipe. Thus, the flange thread should have the same thread specifications as the pipe thread.

The threaded flange advantage is that the piping system would be quite easy to assemble as there would not be any welding in the piping joint.


The threaded flange is usually supplied with a flat face (FF) or raised face (RF) sealing face. When a raised face is essential for the threaded pipe flanges, the standard height needs to be 1/16” for the face under class 400.

If the threaded pipe flanges are more or the same as class 400, the threaded pipe flange raised face needs the height to be 1/4”.

The threaded pipe flange is commonly useful in small sizes and during high-pressure situations. The threaded flange does not have welding in joints, so the flange could be usable in some situations. This way, it is not possible to arrange welding work.

Uses of Threaded flanges

They are beneficial when male NPT pipe connections are useful with high or explosive reactive media. These flanges are commonly used within the oilfield service.

Variety of threaded flanges

There are many available sizes of the flange variety and many pressure ratings. Though this is the case, they are useful most frequently for small piping systems. These piping systems are usually equal to or less than four inches.

Advantages of flanges

The key advantage of the flanges is that you can connect them to the pipes without the involvement of the welding process. It is an advantage and often a necessity. It is essential in the locations and industries that deal with explosive products.

Uses of flange

The common ways where you could use these flanges are:

  • Useful in highly explosive areas
  • Useful in applications where it is hazardous to do welding
  • Flanges are highly economical and help save time
  • Useful in the piping applications of small diameter
  • Can be fitted to various pipe sizes without the need for welding
  • Useful in situations where extreme pressure is present, and post-weld treatment is not an option.

Variety of Flanges Available at Texas Flange

The type of flange used for a piping application usually depends on the required strength for the flanged joint. Flanges are used to weld connections. In addition, it helps to facilitate maintenance operations.

Let’s dive in to show the key types of flanges with pictures.

Forged Flanges

Welding neck flange

A welding neck flange features a long tapered hub that helps weld the pipe. The flange type is normally used in high/low temperatures and high-pressure applications requiring unrestricted flow if the piping system conveys the fluid.

The absence of pressure drops prevents the adverse effects of erosion/corrosion and turbulence of the metals in the flanged joint proximity.

Long welding neck

Long weld neck flanges are quite similar to weld neck flanges. However, it comes with the exception that the neck is extended and acts like a boring extension.

Long weld neck flanges are usually used on barrels, columns, or vessels.

Slip-on flange

You can connect the slip-on flange to the pipe or the fittings by the two fillet welds, one outside and one executed inside the flange cavity.

The bore size of the slip-on flange is large than the outside diameter for pipe connection, as the pipe has to slide inside the flange that you can connect by the execution of the fillet weld.

Threaded flanges

Threaded flanges are joined to the pipes by screwing the pipe onto the flange without the seam welds. Threaded flanges are available in sizes for up to four inches and multiple pressure ratings; however, they are used mostly in low-temperature applications and small-size piping in low-pressure-like air and water utility services.

Socket weld flange

You can connect socket weld flanges to pipes with the use of a single fillet weld executed on the outer flange side.

As per the ASME B31.1, to execute the flanged connection with a socket weld, the pipe must first insert the flange’s socket until it reaches the bottom of the flange. It then needs to be lifted by 1.6 mm and welded finally.

Lap joint flange

The lap joint flange features a flat face and is always useful in conjunction with the stub end. Lap joint flanges usually resemble the shape of slip-on flanges, except for the radius at the flange face crossing and the bore to accommodate the flanged portion of the stub end.

When we talk about the lap joint flange, it can slip over the pipe and seats on the back of the stub end, and you can keep the two together by the pressure of the bolts.

Blind flanges

Contrary to all the flange types above, blind flanges do not have a center hole. Therefore, you can use the seal or blind in a pipeline or a pressure/valve vessel to block the fluid of the liquid.

Blind flanges need to withstand remarkable mechanical stress due to the system pressure and required bolting forces.

You can easily access the blind flanges to the pipeline, as they can be easily unbolted to let the operator execute the activities while inside the terminal end of the pipe.

Interestingly, while this flange type is easy to manufacture, it is sold at the average premium cost per kg compared to the other flange types.

Special types of flanges

The special types of flanges include:

1. Nipoflange

2. Weldoflange

3. Latroflange or Elboflange

4. Swivel flange

5. Expanding flange

6. Reducing flange


The flanges mentioned above are usually the top flanges available to us. However, you can get in touch with Texas flange if you are looking for top-quality flanges. You can also contact us for any queries regarding the flange function.

What is the Function of Flanges and How Do They Work?

The flange industry is wide, and it offers customers a reliable way to connect pipe systems with the various valves, equipment, and other components of virtually any processing system. Flanges are the second most used joining method after welding.

Custom Pipe Flange Fittings

If you use flanges, it adds flexibility when you need to maintain piping systems. It also allows for easy disassembly and improved access to system components.

A typical flanged connection is comprised of three parts:

  • Bolting
  • Gasket
  • Pipe flanges

In many cases, specific bolting and gasket materials are made from the same or approved materials as the piping components you wish to connect. For example, stainless steel flanges are the top choice among some of the most common flanges. However, flanges are available in a wide range of materials, so matching them with your needs is crucial.

Other common flange materials include Chrome Moly, Inconel, Monel, and many others, depending on the application.

The best option for your needs depends on the system in which you intend to use the flange and your specific requirements.

Common flange types and characteristics

Flanges are not a one-type-fits-all kind of solution. If we keep the sizing aside, matching the ideal flange design to your piping system and intended usage will help to ensure optimal pricing, a long service life, and reliable operation.

Here are the most commonly available flange types:

Threaded flanges

It is also known as a screwed flange and has a style with thread inside. The flange bore fits with the matching male thread on the fitting or pipe. The threaded connections mean you can avoid welding in many use cases. If you simply match the threading o the pipes, you wish to connect.

Socket-weld flanges

Ideal for small pipe diameters in low-pressure and low-temperature scenarios, socket-weld flanges feature a connection where you place the pipe into the flange and then secure the connection with a single multi-pass fillet weld. As a result, it makes the style simpler to install compared to other welded flange types while avoiding the limitations associated with the threaded ends.

Slip-on flanges

Slip-on flanges are quite common and are available in large-size ranges. It can accommodate systems with high flow rates and throughput. You intend to connect if you match the flange to the outer pipe diameter. Installation is slightly more as you will need to fillet the weld on both sides to secure the pipe flange.

Lap joint flanges

Lap joint flanges require butt welding of the stub end to the fitting or pipe with a backing flange to create a flanged connection. The design makes this style popular for use in systems with physical systems or space that requires frequent maintenance and dismantling.

Weld neck flanges

Weld neck flanges need butt welding for installation. However, its performance, integrity in the systems with multiple repeat bends, and the ability to use them at high temperatures and high pressure make them a top choice for processing piping.

Blind flanges

Useful for isolation or terminating piping systems, blind flanges are essentially boltable blank discs. When you install them properly and combine them with the correct gaskets, it can achieve an outstanding seal that is easy to remove when needed.

Specialty flanges

The flanges types listed above are quite common. However, various specialized flange types are available to suit various environments and uses. Other options include reducing flanges, orifice, expanding flanges, weld flanges, and nipo flanges.

Flange Facing Types: Making the connection

The design is just a start when you consider the ideal flange for your piping system. Face types are another characteristic that greatly impacts your flanges’ service life and final performance.

Facing types determine the gaskets required to install the characteristics and the flange related to the seal created.

Common face types include:

  • Flat Face (FF)
  • Raised Face (RF)
  • Ring Joint Face (RTJ)
  • Tongue and Groove (T&G)
  • Male & Female (M&F)

Most face types offer one of the two finishes: smooth or serrated. Choosing between the options is crucial as it will determine the optimal gasket for a reliable seal. In general, smooth faces work best with metallic gaskets, while serrated faces help create stronger seals with soft material gaskets.

Flanges Dimensions: The Proper Fit

Apart from the functional flange design, flange dimensions are the most likely factor that impacts the flange choices when updating, maintaining, or designing a piping system. First, however, you must consider how the flange interfaces with the pipe and the gaskets in use to ensure proper sizing.

Common considerations include:

  • Nominal bore size
  • Pipe size
  • Bolt circle diameter
  • Thickness
  • Outside diameter

Flange classification and service ratings

The above characteristics will influence how the flange performs across various environments and processes.

Flanges are often classified based on their ability to withstand pressures and temperatures. It is designated using a number and either ‘class,’ ‘lb,’ or ‘#’ suffix. These suffixes are interchangeable but will differ based on the vendor or region.

Common classifications include:

  • 150#
  • 300#
  • 600#
  • 900#
  • 1500#
  • 2500#

Flange markings and standards

To make the comparison easy, flanges fall under global standards established by the ASME (American Society of Mechanical Engineers) – ASME B16.5 & B16.47.

If you are attempting to verify or replace the existing parts, all flanges must include the markers, typically on their outer perimeter, to aid in the process.


The above guide offers you a solid foundation of the basics of flange design and how to choose the ideal flange for your piping system. However, with a wide range of stainless steel flanges or other available flange materials, it is impossible to list every consideration, detail, or configuration.

You can contact Texas flange if you want the best quality flanges or have any queries regarding the flange function.

When and Why Should You Use Flange Fittings?

Flange fittings are the components helpful in joining the pipe sections together with other fluid control products like pumps and valves to create pipelines. The common connotation for the term fittings is associated with the ones which are helpful for plastic and metal pipes carrying fluids.

However, other pipe fittings help connect pipes for handrails and other architectural elements, where providing a leak-proof connection is unnecessary. You may be more familiar with those in your day-to-day life.

Flange Fittings

About Flange Fittings

Flange fittings may be mechanically joined, threaded or welded, and chemically adhered  (to name the most common mechanisms depending on the pipe material).

There’s been an inconsistency in terminology surrounding tubing, tube, and pipe. Therefore, the term pipe fittings will be mentioned sometimes in tubing specs. While similar to tube fittings, pipe fittings are joined by methods like soldering and less like common welds. Few ways tend to overlap, like compression fittings, but where these are commonplace for connecting tubing or tubes, their use in pipe connections is rare.

Use of alternate flange fittings in other industries

The fluid power industry is shifting to connections with an elastomeric O-ring seal. It helps to minimize leakages. These fittings include the threaded face seal, ISO 6149, SAE J518, flange fittings, and flanges (Code 62 and Code 61), where the O-ring seal is compatible with the fluid.

A captive flange is often practical when you fit tube-to-tube (or hose or pipe). Captive flange fittings slip over the flared tubes and have an excellent connection to the mating flange or other components. Captive flanges are commonly used with MJ-Flange Straight fittings. There is a smooth clearance to slide over the fittings and seat on the head of the flange. Split flanges are helpful with 90 or 45 flange fittings.

Benefits of flange fittings

Even though there are specific applications where flange fittings and flanges are the only choices, flanges provide benefits to the piping system that traditional hydraulic fitting types do not give. For example, in the ones with larger OD applications, flanges can connect to the pipe and components ports more easily than adapters or threaded fittings. Most importantly, in most of the severe service applications on mobile construction equipment, flanged connections are best for:

  • Easy assembly in tight spaces where wrenches might not have clearance to install the traditional flange fittings. They are more easily assembled with moderate torque.
  • These are hard-to-reach areas that require flexibility. For example, it needs to eliminate the need for pipe or hose lines, adapters in the tube, etc.
  • Pipe, tube, or extensive hose connections where high pressure, vibration, shock, and pressure surges are present could damage the traditional large hydraulic fitting more easily.
  • It makes connections that allow easy maintenance in rigid lines like continuous metal tubes and pipes.
  • Reduce the chances of components becoming loose in rigorous hydraulic applications.

When to use flange fitting

With flange connections in this larger size, high-pressure circumstances allow for easier assembly than overusing the large fittings. In addition, the flange fittings have a zero-clearance assembly, easy disconnecting, and reconnecting to maintain manifold, tube, and hose connections. As a result, it can be much faster and can provide for more accurate torque of the bolts instead of achieving the proper torque of a large fitting.


Flange fittings connections are much less likely to be loosened than the standard hydraulic fitting with the proper load distribution of clamping around the flange head. On the other hand, flange connections are the best option for hose-end connections with bends. This is because they are subjected to very high lateral forces inclined to cause assembly loosening.

If you are interested in flange fittings, contact Texas Flange today!

Factors to Consider When Choosing Flanges for Your Project

Gas and oil plants are complex, large environments with thousands of miles of interconnected piping. For any flange or product to perform correctly, choosing the right type of flange for the job is fundamental. The flange must fit perfectly into the pipe joint to conduct its functions properly. A minor mistake during the flange selection may affect an application resulting in an expensive error.


This blog will discuss the factors associated with selecting the correct flange for the proper application to ensure maximum usability.


It is often easy to spot the flange type by the way it looks. First, you must classify the top of the flange by deciding whether the flange has a socket weld, flat flange, lap joint, threaded bore, welded neck, groove, and tongue flange. Next, the bottoms are identified with the evaluation of whether they have a flat face, which is entirely flat, or a raised face which is a slightly raised section on the face of the flange.

All of this information is usually defined by the stamping on the outside diameter of the flange, provided this has not been completely painted over. It is important to keep an archive of your assembly components for future reference and maintenance.


The flange size consists of factors that include the standard used (: JIS – Japanese International Standard, ANSI – American National Standards Institute, and DIN – Deutsches Institut für Normung / European), the pressure level needed, and the actual overall outside diameter and thickness of the flange. Other factors in determining the full call-out include the number of bolt holes, outer diameter, inner diameter, bolt circle, and bolt hole diameter, but the nominal pipe size is typically universal.


Depending on the flange thickness, it can be determined how high a pressure flange can handle, in any application thicker flanges can resist high pressures.

Bolt holes

Bolt holes help to measure the flange size and pressure class. The actual size of the bolt holes, the pitch circle diameter, and the number of bolt holes on the flange are three factors that need to be addressed. If the bolt is stronger and thicker, it can often correlate with higher pressure capabilities.


There are a lot of industry-defined standards from which you can choose the flanges. So the flanges help to choose based on the standard and application of the product. You can connect it to the three primary standards previously mentioned, including DIN, ANSI, and JIS.

Pressure class

Pressure class signifies the marginal pressure level under which the flange can safely function and sustain. Each standard comes with several pressure levels available, from high-pressure to low-pressure tolerance. The pressure levels of products connected to the flanges must be the same as those of valves and pipes in service. The most common industry pressure class is the modern ASME 150# per B16 spec.


It is crucial to choose a suitable material for a flange depending on the understanding and application the elements will encounter in an application that the piping system is using. The most common materials include chrome, nickel, carbon steel, duplex steel, stainless steel, etc.

Here are a few common ways to choose the flanges:

Define your specification and standard

Pipe flanges come in with standard blind, threaded, weld neck configurations. As fittings come into standard, oilfield dimensions become necessary for functional interchangeability.

Standard dimensions are the same for all materials used. However, the specifications are regularly updated, broadened, and revised.

Figure out the flange facing

Defining the facing of your flange is one of the first steps to order the industrial pipe fittings. The flange face is the sealing surface. The most common types of flange faces include:

. Full face
. Flat face
. Ring-type face
. Large female and male
. Lap joint
. Raised face

Pick put the correct pressure class

The pressure class of the flange standard determines its dimensions. The pressure class ratings may fall within 125 to 900 psi. The four factors which influence the pressure limits of the flange within the oil and gas industry include:

. Flange sizes
. Materials used
. External and internal temperatures
. Size of bolts, number, thickness, and dimensions


You may need to consult the fitting distributor to determine your project’s right flange pressure class. For more information on sourcing suitable flanges for your project, you can reach out to Texas Flange.

5 Best Tips to Use Steel Pipe Flanges For The First Time

A pipe flange is a mechanical device that serves the purpose of joining the pipes together. It can be in the form of a welding neck where it is welded to a pipe or other butt-weld fittings.

The threaded flange or flange collar is screwed to the flange with a companion pipe. Other methods include using a lap joint to make connections using a stub end, as well as the common slip-on and socket weld connections.

Steel pipe flanges

Here are five tips for using the steel pipe flange for the first time:

Slip-on flanges for low-pressure services

The preference of slip-on flanges is mainly by the users who prefer flanges that are easy to use, have less installation time, and have low cost.

In addition, they are helpful for non-critical low-pressure services like firewater, cooling water, and other non-challenging pipework owing to their strength being approximately 1/3 lower than that of a weld neck flange, depending on the assembly. The pipe gets welded to the flange hub and bore.

If you want to check on the integrity of the slip-on connection, a magnetic particle, a simple visual test, or a PT test are the approaches you can follow. You can use the slip-on flanges, which come in a variety of sizes greater than NPS ½ (DN 15).

Socket weld flanges in high-pressure pipe works

If you do high-pressure pipework below 2 inches (DN50), a socket weld flange is preferable when space is constrained. It would help if you filleted weld the pipe to the socket weld flange hub. A good welding flange experience is crucial to make the connection since a radiographic examination on the fillet weld is not easy to execute.

If, however, the connection is visual and critical, examination alone will not be enough if it carries out the magnetic failure or penetrates particle tests to check the connection strength.

Lap joint flange in high-cost material pipelines

The working of lap joint connections is good for pipelines that are in high-cost materials such as stainless steel and nickel alloys. It dramatically reduces the total cost of all flanged connections which is required. The stub end, which has been welded to the pipe, and the backing or lapped flanges are used to make a lap joint connection.

You may, for instance, use the stainless steel stub end combined with a carbon steel lap joint flange for a good welded connection at lower costs. This is becoming an increasingly common alternative as the volatility of steel prices becomes an issue.

Connecting weld neck flanges to the butt weld for good performance

There is a tapered hub on the weld-neck flanges. It comes with an end that’s finished as a butt weld and can be connected to butt weld pipe and fittings. You can examine the weld’s quality with ultrasound radiography or visually do it.

The welded connection of weld neck flange or pipe flange features good fatigue as well as mechanical stress performance.

Skilled professionals execute the pipe flange joint process

Trained personnel must be the ones to execute flange joint seals. It helps to prevent dangerous leaks from happening in the pipeline. With the first time use of steel pipes, a properly trained engineer must be the one to execute flange ring joint connections and reference the correct bolt torque data.


Steel pipe flanges are often the best solutions to your multi-stage pipe assemblies, but the material grade is also of concern. Stainless steel is a corrosion-resistant, durable, strong metal, making it an excellent choice for flange fittings in the gas and oil industry when carbon steel will not suffice. If you want more information on steel pipe flanges, contact Texas Flange.

Stainless Steel Flange Buying Guide

A flange casting is typically a cast ring designed to connect the sections of a pipe or other machinery which requires a connecting joint.

Most cast options are outdated and flanges provided to modern specifications are made from plate or forged carbon steel or stainless steel. Before you buy flanges, it is crucial to note that these flanges come in different measurements, diameters, sizes, types/forms, and materials.

Several types of flanges are available for different types of applications. Therefore, all you have to do is choose your product on a per-project basis. When we talk about the materials to use in your applications, a variety of factors come into play. Therefore, some crucial aspects that are required to be considered while buying stainless steel flanges are discussed in this blog:

Choose the right stainless steel flange

It is crucial to note the diameter of the pipes to which the flange needs to be connected. Also, you must understand that these pipe connections could be ERW, welded, seamless, etc., and would help you choose the required flanges.

Stainless steel pipe flanges, rings, and discs attach to the pipe to increase the strength or support based on the existing connection type from the pipe, which are usually welded or screwed to the pipe end. These pipe flanges are designed per the specifications and are easy to customize by established manufacturers.

Choose the flanges based on the project design

SS Flanges are accessible in numerous grades. The client’s selection of products needs to rely on the budget and project you need. However, top-quality products need to be costly and need to be sturdy.

Both SS 316L Flanges and SS 304L Flanges are corrosion resistant alloys with a high, 95% alloy composition. SS 316 and SS 304 belong to the chromium-nickel category and are grades that withstand standard corrosion. It needs to be durable, resists most basic chemicals, and hold more excellent resistance to numerous types of deterioration.

Selecting SS Flange types available in market

Here’s how you can select the SS flange types available around the market:

SS Slip-on flanges

The bore size of the slip-on flange as a standard is slightly larger compared to the outside diameter of the connecting pipe, as the pipe has to slide inside the flange then needs to be connected by the execution of the fillet weld around the perimeter.

SS Weld neck flanges

SS Weld neck flanges are helpful in high/low-temperature applications and high-pressures that require an unrestricted fluid flow conveyed by the piping system. These butt-weld end connection flanges are most common in industrial applications to ensure a high strength connection between assemblies.

SS Blind Flanges

Most piping systems require regular inspection and blind/blank flanges are common inspection point. This type of flange, when selected according to the proper pressure class, can easily handle the stress caused by the liquid’s operating pressure and pressure flowing through the pipe. They are helpful to ‘blank off’ valves, pipelines, etc… in almost all applications.

SS Threaded Flanges

You can assemble the flange without welding, and hence it is easy to remove. You do not have to use it for applications where bending stresses involve high pressure or temperatures. A seal weld is useful in conjunctions with times.

SS Lap joint flanges

It is a type of slip-on flange but made for connecting to a stub end for rotation. Lap joints are helpful to maintain carbon/low alloy steel pipes with additional mechanical properties. These flanges are similar to slip-on flanges but are characterized by the radius-rounded interior edge of the flange face and generally come with a taller hub.

SS Socket-weld flanges

Smaller diameter socket weld and counter bore flanges handle the applications with high pressures like steam lines but with limited spacing. You must ensure durability possess internal welds—the bore of the pipe and flange match provides a good flow connection.

SS Orifice flanges

If you want to combine two pipeline components in assemblies for which you need easy access to modify, inspect, and clean, orifice sets are commonly recommended. Types need to vary as per the use and maintain high-pressure applications, and line blanks are also usually installed for maintenance or operating differentials.


Even if you find a range of flanges in the market, we offer you the best quality for your establishment. Nothing can beat stainless steel flanges in most lighter corrosion applications. The above blog signifies the buying guide of stainless steel flanges above; we hope you’ve now good knowledge about various steel flanges and whether they are the best option for you or not.

If you want any specific information, then contact Texas Flange today!


Flanges Used In The Oil and Gas Industry

Connections through pipes are a crucial channel for transporting steam and fluids along with gas from refineries to factories or across continents as well. Flanges are one of the efficient components in a method to connect pipes. Along with forging connections in a piping system,

flanges regularly permit the worker with inspection points which are easy to modify and clean these systems. Different alloy grades are useful to produce various flanges that are a part of piping systems in the gas and oil industry.

Therefore, these flanges are required to not only be durable, but they must also be easy to install and maintain.


Below are a few of the commonly sighted flange types used in the gas and oil industry:

Weld Neck Flange

Useful in high-pressure environments, it is easy to recognize the weld neck flanges because of the beveled hub. Moreover, weld neck flanges are particularly well suited to be used in repeat bending conditions. These flanges are attached to a piping system by means of welding the pipe to the flange neck.

Therefore, stainless steel grades have good weldable properties preferred for its manufacture. Weld neck types not only reduce the stress concentration from the base of the hub but also aid the transference of stress from the flange to the pipe.

Slip-on Flange

Slip-on flanges are designed to be used in lower-pressure, low-temperature processes. These are favored by the engineers in the gas and oil industry due to their economical value in comparison to the weld neck flanges.

This kind of flange is slipped over the pipe, following which they are welded both on the outside and inside to increase its strength and prevent leakage.

Lap joint

A lap joint flange is a two-part attachment preferred to be used in processes where space constraints and frequent dismantling are primary requirements. In this type of attachment, the lap joint stub end is welded to the pipe, and the loose backing flange is used in conjunction to slip over the pipe or stub end.

As the backing flange is not in contact with the product in the piping systems, moderate corrosion resistance and less expensive material with high hardness like carbon steel is good to use. Also, the stub ends need to be highly corrosion-resistant material with good mechanical properties.

Threaded Flange

It is useful in circumstances where there’s a need for quick fixes. Threaded flanges or as referred to as screwed flanges are produced with threaded bores that aid in a fast and simple attachment.

A threaded flange is usually attached to the pipe without a need to carry out a welding operation due to the pre-existing threads. Typically, threaded flanges are seen in the processes where the pipes in the systems are used to transport water or air. Threaded flanges are best used in low-pressure environments and temperatures.

Blind Flange

The production of blind flange is done without a bore at the center and the main purpose of using it is to blank off the end of valves or piping systems or even pressure vessel openings.

Blind flanges could also be used in conjunction with any other flange to isolate a piping system in the gas and oil industry. Furthermore, they make an excellent manhole, especially if they perform the tasks of terminating the flow in the vessel or a piping system.

Socket Weld Flange

It is recommended to be used for low-temperature and low-pressure settings, the socket weld has a static strength that is equal to a slip-on flange. A socket-weld connection is made with the pipe by using a filler weld performed on the outside of the flange.

Socket weld flanges are designed to be used in processes where small bore piping is needed. However, due to some corrosion issues, it is best to avoid these in a few processes.

If you still have any doubts about how to select flanges for the oil and gas industry and what to look for, do let us know in the comment section or call us today!

Carbon Steel Flanges: Types and Functions

Flanges are useful to connect valves, pumps, and pipes for the piping system. There are different types of flanges like welded, lap joints, blinds, and many others. The use of carbon steel flanges is widely high in demand. The reason is its excellent features like excellent durability, corrosion resistance, and finishing.

It is useful in various industries. These include agriculture, power, chemical, petrochemical, and others. The flange is an internal or external edge, or a rim (lip), for power like an iron plate flange, such as a T-beam or I-beam; or attachment to another component like a flange at the end of the screw, a steam lever, etc.

Type of carbon steel flanges

There are mainly 6 types of carbon steel flanges available for use. These are the 4 most common:

Welding neck flange

Welding neck flanges are popular for their long tapered neck, with the accompanying connection, and their end is welded to the bottom. The internal diameter of the pipe is the same as the flange. It is useful in extreme jobs where there is a requirement of high stress.

Sliding flanges (slip on)

Slip on Flanges

The tube penetrates the cube of the same as in the form of carbon steel flanges. You do not need to touch the plane to the face to which it is connected with the use of external and internal welding seams. Due to the lower accuracy of the tube life and better positioning flexibility, we can consider it simpler than the neck flange. The mechanical condition of the sliding flange is usually good for exhaustion and strength, but much weaker than the neck-straps.

Blind Flanges

The design is such that it covers the ends of the tube openings, valves, or tubing due to various operating pressures. It is a form of ASME fitting that from a technological point of view is capable to withstand the most extreme working conditions.

Threaded Flanges

Although they do not possess any welding characteristics, they make assembly easy and quick. It is useful for specific applications (e.g., in pipes with high atmospheric temperatures and pressures) where male NPT threaded pipes are utilized.

Characteristics of carbon steel flanges

There are different diameters of Carbon steel flanges that are popular. One of the main reasons is its easy installation and cheap cost. Another advantage of carbon steel flanges is that they can be used as connecting flanges when they work with Type B and Type C ends.

Unlike weld-neck flanges, they do not have a neck to rest on the pipe and, therefore, require double welding. The characteristics of carbon steel flanges include:

. Available in a wide range of diameters

. They take minimal vertical flange space.

. Easy installation and assembly

. Low cost

Reason to use Carbon Steel Flanges

Carbon steel or medium carbon steel is an element of metal. It is a mixture of carbon and iron components. Many components are too small to influence their properties in amounts. In pure carbon steel, the only other elements permitted are: copper (0.60% max), silicon (0.60% max), and manganese (1.65% max).

With more carbon content, the carbon steel flanges achieve toughness and strength. These are less tough and ductile to weld. Higher carbon content decreases the flange melting point and its tolerance to temperature.

The function of the carbon steel flanges

Forged flanges are less carbon-free than molten flanges. They do not oxidize quickly. These flanges are also flat, and the construction of these flanges is fairly lightweight. It also has superior mechanical properties. Improper forging may result in irregular or broad grains. It is higher to harden forging and cracking than the casting flange.

According to the manufacturing cycle, the forging flange comes in a few operational theories in the carbon steel flanges. The usage and production method of the carbon steel flange provide an operating theory. Its basic philosophy is using the insulation efficiency of the carbon steel flange isolating gasket.


Choosing a carbon steel flange means getting the best flange for industrial operations. The types and functions of the carbon steel flanges determine that the flange material is best to use. At Texas Flange, we offer all types of flanges for various systems. Our specialists can help you to identify the right flange for your equipment. If you want more information, contact us today!

What are the Various Factors to Identify Suitable Flanges for Your Work?

It is crucial to choose the right flange for the application. If you want the flange to function, it must fit perfectly into the pipe joints. If you make one slight mistake while selecting the flange, it may affect the application and result in a costly error. For optimum usability, you can address the considerations relevant to choosing the right flange that goes well with the applications.


Flange Size

The flange size consists of several variables. These include the right pressure class, standards used, and right flange measurement. The inner diameter, outer diameter, number of bolt holes, the diameter of the bolt holes, and the bolt circle are influences. Flanges are available in many sizes ranging from 48″ (1200NB) to 1/2″ (15NB).

Flange Types

If you identify the flange type by its appearance, it is usually easy. Decide whether the flange has a socket weld, solder collar neck, lap joint, threaded bore, or flat face and that defines the basics.

You can start by choosing if it has a flat face that is completely raised or a flat face that is a slightly raised portion on the flange face with marked bottoms. There are many different types of flanges as indicated previously, in various material grades of carbon and stainless steel.

Flange Thickness

Define a flange by how it handles the high pressure. Apart from this, thickness plays a crucial role as thicker flanges can better handle higher pressures in an application.

Bolt Holes

The pressure class and size of the flange helps to determine this component. The actual size, pitch circle diameter, and the number of bolt holes, on the flanges, are the three variables that need consideration. The stronger and heavier bolt results in higher pressure that withstands the flange. The pattern must match up to the item the flange is bolting to.

Flange Standards

You can find a range in criteria that makes it tough to choose the flange standard. It is most likely that the choice is based on the standards and application of other components to which the flanges are linked. The three major standards used are JIS (Japanese International Standard), DIN (Deutsches Institut für Normung / European), and ANSI (American National Standards Institute).

Pressure Class

The pressure class is the nominal pressure quality that the product can safely work under or support. There are many pressure groups available for each standard, and it ranges from high-pressure tolerance to low-pressure tolerance. The pressure class of the items that operate together must be the same as the pressure class of the valves and pipes in the system to the ones they are connected. The pressure class of carbon and stainless steel flanges ranges from 2500#, 900#, 600#, 400#, 300#, 150#, and so on.

Flange Materials

It is crucial to select the right material for a flange. You must know the elements it will face in an application that uses the piping method is essential. Common materials include copper nickel, carbon steel, stainless steel, and steel. The supporting materials of these flanges, such as stainless Steel 317 flanges, are flange bolts, ring joining, and gaskets.

Other factors for selecting flanges

Consider the tolerances, flange dimensions, temperature and pressure ratings, and pipe materials to determine the appropriate flange material. ANSI ratings help to provide information on heat and pressure tolerances. The fitting type is one of the crucial things to consider. The material you choose must allow welding. For non-welded styles like lap joints or threaded flanges, weldability is not a major concern, and other requirements will take precedence.


Choosing the ideal flange for work refers to the standards required for your intended application. You must consider the pipe material that can connect to the flange and ensure that the flange material you choose is rated for the pressure and temperature it must withstand.

At Texas Flange, we offer all types of flanges for various systems. Our specialists can help you to identify the right flange for your equipment. If you want more information, contact us today!