How to choose the best flange for your project

An engineering project involves many decisions. Some of those involve the materials to be used, such as the most suitable type of flange.

What are metal flanges and what are they used for?

Forged flanges are used to connect elements such as pipes, valves, pumps or the various components of a piping system. Pairs of forged flanges are held together with bolts and a gasket located between the two. The aim is to achieve a solid system that guarantees watertightness, but can be opened to facilitate cleaning, or inspection and maintenance tasks.

Applications for forged flanges

Due to their strength and load capacity, forged flanges are used in many industries. They are commonly used outdoors in industries such as petrochemicals, solar energy or waste water treatment, and also in medicine and the food industry.

How do you choose the best material for the flanges?

Forged flanges can be made of different materials. When deciding between them, you need to keep in mind the environmental conditions and stresses that the flange will be subjected to. 

  • Carbon steel flanges, for example, are suitable for environments with moderate temperatures.
  • If the flange will have to withstand more extreme conditions, however, either in terms of temperature or pressure, alloy steels are recommended.
  • If the flange is to come into contact with corrosive liquids or gases, alloys made of metals such as nickel, chrome and molybdenum are often used.

Metal flanges can be produced by various methods, such as casting or forging.

How do you choose the right type of flange?

Welding neck, slip-on, armor… There are many types of metal flanges, and they can be used for completely different purposes. Here are some examples.

Welding neck flanges:

These have a long neck of the same diameter as the pipe to facilitate butt-welding. They are recommended for extreme conditions, i.e., high temperature or high pressure, with flammable or corrosive liquids, or in those environments where leakage must be kept to a minimum.

Slip-on flanges:

In this case the pipe is not butt welded, but goes inside the flange. They are easier to install, but their mechanical durability with respect to resistance and fatigue are lower than welding neck flanges, so they are used for low pressure fluids that are low-risk in case of leakage.

Socket welding flanges:

These flanges have a pipe that goes into the flange until it comes to rest on a seat with the same internal diameter as the pipe. Their wider range of application facilitates their use in small size pipes for high pressure fluids.

Threaded flanges and Lap-Joint flanges

These two types of flanges have holes through which connecting bolts are attached, which facilitates disassembly. Therefore they are used in structures that need to be opened frequently.

Blind flanges

These are flanges without a hole in the middle that are used to close off the ends of piping systems or pressure vessels. They are mainly used in high pressure applications, to prevent the flow of liquids or gases.

Reducing flanges

These are designed to connect pipes of different sizes.

The above are just a few examples of forged flanges, but in case of doubt, it is always recommended to seek the advice of experts in the field.

Flanges from ULMA Forged Solutions Flanges

At ULMA Forged Solutions, we manufacture a wide variety of forged flanges. In our catalog you can find parts ranging from 0.5 to 102 inches, covering all pressure ranges and all kinds of different alloys.

Although our product range is very wide, we are aware that each engineering project has specific needs, so we also design, engineer and produce custom-made flanges based customer and project needs.

All flanges from ULMA Forged Solutions comply with ASME B16.5, ASME B16.47 and MSS SP-44 standards, so their functionality is guaranteed and replacement is facilitated in case of defects.