What are Flanges?

Flanges are a type of fitting that is used in pipe and tubing systems. It’s often used in metalworking and engineering for joining pipes, valves, pumps and other equipment together so that they can work smoothly as one unit. They offer the advantages of being able to connect different types of materials together, while also allowing flexibility for when components need to be removed or replaced. A flange can have female ends (such as on a steel beam) where it would receive bolts from another component, or male ends (such as on a steel pipe) where it would connect to another component.

What are Flanges Used For?

To reduce pressure or strain exerted on pipelines without reducing fluid flow rate – Connecting large diameter piping systems together in power plants, refineries, chemical plants – To connect and disconnect piping systems

Facilitating repairs in pipelines by making it easier to access them (e.g., when an emergency shutdown is required) or relocating a pipeline

Materials for Flanges

Stainless Steel

Mild Steel

Types of Flanges

Threaded Flange

Also known as a screwed flange, this style has a thread inside the flange bore which fits with the matching male thread on the pipe or fitting. The threaded connection means you can avoid welding in many use cases. Simply match the threading to the pipes you wish to connect.

Socket-Weld Flanges

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

Slip-on Flanges

Slip-on flanges are very common and are available in a large range of sizes to accommodate systems with higher flow rates and throughput. Simply match the flange to the outer diameter of the pipe you intend to connect. Installation is slightly more technical as you’ll need fillet weld both sides to secure the flange to the pipe.

Lap Joint Flanges

Featuring a two-piece design, lap joint flanges require butt welding of the stub end to the pipe or fitting with the use of a backing flange to create the flanged connection. This design makes this style popular for use in systems with limited physical space or systems which require frequent dismantling and maintenance.

Weld Neck Flanges

Like lap joint flanges, weld neck flanges require butt welding for installation. However, their integrity, performance in systems with multiple repeat bends, and the ability to use them in high-pressure and high-temperature systems make them a leading choice for process piping.

Blind Flanges

Used for terminating or isolating piping systems, blind flanges are essentially boltable blank discs. When installed properly and combined with the correct gaskets, they can achieve an outstanding seal which is easy to remove when needed.

Specialty Flanges

The flange types listed above are the most common. However, there is a range of additional specialized flange types available to suit a range of uses and environments. Other options include nipoflanges, weldoflanges, expanding flanges, orifice, long weld neck and reducing flanges.

Flange Dimensions and Common Considerations

Other than the functional design of a flange, its dimensions are the most likely factors which has an on the choices of impact flange while designing, maintaining and updating the piping system. Whereas one must consider the interfaces of flange with the pipe and the gasket which are in use in order to ensure the proper sizing. Other than this some of the common considerations are as follows:

Outside diameter

The outside diameter refers to the distance between the two opposing edges of the flange face.

Thickness

The thickness is measured from the outer side of the rim.

Bolt circle diameter

This is referred to as the distance between the opposing bolt holes which is measured from Centre to Centre.

Pipe size

Pipe size refers to as that dimension through which the flange gets corresponded.

Nominal bore size

Nominal bore size is the measurement of inner diameter of the flange connector.

Common face types include:

Making the Connection: Flange Facing Types

Flange design is only the start when considering the ideal flange for your piping system. Face types are another characteristic that will have a major impact on the final performance and service life of your flanges.

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

Applications of flanges

A flange is a method of connecting pipes, valves, pumps, and other equipment to form a piping system. It also provides easy access for cleaning, inspection, or modification. Flanges are usually welded or screwed.

In many applications, engineers need to find a way to close off a chamber or cylinder in a very secure fashion, usually because the substance inside must differ from the substance outside in composition or pressure.

They do this by fastening two pieces of metal or other material together with a circle of bolts on a lip. This “lip” is a flange.

Plumbing

Mechanics

Electronics

Enquire Now