Flanges are a crucial component used to join valves, pipes, and pumps within a piping system. They are the most commonly used connection (after welding), and offer a range of benefits  – primarily in providing access for intervention (inspection, maintenance, or repair), or as end-points in a system.

Flanges are an integral part of pipe system solutions, and are second only to welding to join pipes together. Your steel pipe stockist will offer various options on the best flange type to use for your specific application. Flanges are especially relied on in situations where solvent cementing cannot hold, as well as in situations such as dismantling a piping system, using a temporary or mobile installation, or when two materials have to transition into one another.

 The global market size for flanges was valued at $4.50 billion in 2021, and is estimated to reach $7.39 billion by 2031, growing at a CAGR of 5% from 2022 to 2031. In addition to the continued strength of the manufacturing, oil & gas, and process industries, a key driver of this growth is the adoption of control technologies for reducing costs from wastage of liquids passing through piping systems in facilities across energy, power, civil, and process industries1. Underlying this growth and making it possible is the adoption of international standards that allow for the connection of different pipe system materials from different manufacturers across the globe.


Flanges are rated according to the type of service, material requirement, weight, pressure, and temperature, as well as other safety and application considerations of the system they are used for. These standards define certain criteria that must be met to facilitate the use of products from various manufacturers across a piping system. Flanges are typically installed on valves larger than DN50 (2’’), while, threaded-type valves are typically used for sizes smaller than DN50 (2’’).

Flanges are typically built to the American National Standards Institute (ANSI) ANSI Standard B16.5 (or DIN or other equivalent international standards). Together with the ASME (American Society of Mechanical Engineers), they have developed and published the definitive standard for flange connections: ASME/ANSI B16.5. Although not exactly the same, the equivalent European standard is DIN (an acronym for the German translation of “German Institute for Standardization”). The DIN standard for pipe flanges is DIN EN 1092-1. This standard is also recognized by the International Standards Organization (ISO) under ISO 7005.

Types of Flanges

Flanges come in a wide range of materials, including brass, copper, and iron, as well as in carbon, alloy, and stainless steel. They can also be adapted to different applications and functions. Among the most commonly used types of flanges are:

  • Flange Blind
  • Flange Socketweld
  • Flange Slip On
  • Flange Spectacle
  • Flange Weldneck
  • Flange Threaded
  • Flange Spacer
  • Flange Long Weldneck
  • Flange Orifice Weldneck
  • Flange Spade
  • Flange Reducing Slip On
  • Flange Lap Joint
  • Flange Reducing Threaded
  • Nipo Flange
  • Weldo Flange
  • Flange Reducing Socket Weld
  • Flange Reducing Weldneck
  • Flange Orifice Slip On
  • Flange Orifice Threaded

Depending on the pipe system requirements, flanges offer safety, flexibility, and versatility in joining various parts of a network to each other.

Flanges Connections

Gerab National Enterprises

As one of the most trusted pipe suppliers in the UAE, Gerab supplies a wide range of ASME flanges in classes from 150 to 2,500 and API flanges in classes from 2,000 to 20,000. Flanges such as swivel, orifice assembly, anchor, and long weld-neck flanges in standard dimensions can also be sourced and supplied on request3. 

Crucially, Gerab also supplies the necessary experience and expertise in handling flanges and supports its clients with a comprehensive range of services for their proper functioning. This includes help with selecting the appropriate equipment, installation (where care should be taken to line the flanges and tighten the bolts with the same torque in order to create a strong seal), machining, and repair. As steel pipe stockists of high regard, Gerab also provide the ancillary materials required for their installation, such as gaskets and the sealing components used to ensure tightness, all under a Quality Management System that ensures compliance with the highest local and international standards.