Flange

Flange

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 into such systems and then joined with bolts.

Types of Flanges

There are several types of flanges, each serving different purposes and applications:

• Weld neck flange: This type of flange is designed to be welded to the pipe. It is known for its high strength and is used in high-pressure applications.
• Slip-on flange: This flange is slipped over the pipe and then welded both inside and outside to provide sufficient strength and prevent leakage.
• Socket weld flange: This type of flange is used for small-diameter, high-pressure pipes. The pipe is inserted into the socket end and then fillet welded around the top.
• Lap joint flange: This flange is used with a stub end, which is welded to the pipe. The flange itself is not welded or fixed to the pipe, allowing it to rotate for easy alignment.
• Threaded flange: This flange is screwed onto the pipe, making it suitable for low-pressure applications where welding is not feasible.
• Blind flange: This is a solid flange used to close off the end of a piping system or a vessel opening.

Materials

Flanges are made from various materials, depending on the application and the environment in which they will be used. Common materials include:

• Stainless steel
• Carbon steel
• Alloy steel
• Aluminum
• Brass
• Plastic

Applications

Flanges are used in a wide range of industries, including:

• Oil and gas industry
• Chemical industry
• Water treatment
• Power generation
• Food and beverage industry
• Pharmaceutical industry

Standards

Flanges are manufactured according to various international standards to ensure compatibility and reliability. Some of the most common standards include:

• American Society of Mechanical Engineers (ASME)
• International Organization for Standardization (ISO)
• Deutsches Institut für Normung (DIN)
• British Standards (BS)

Installation

Proper installation of flanges is crucial to ensure the integrity of the piping system. The process typically involves:

• Aligning the flanges
• Inserting the gasket between the flanges
• Tightening the bolts in a star pattern to ensure even pressure distribution

Maintenance

Regular maintenance of flanges is essential to prevent leaks and ensure the longevity of the piping system. This includes:

• Inspecting for signs of wear or damage
• Replacing gaskets as needed
• Ensuring bolts are properly tightened

See Also

• Gasket
• Pipe (fluid conveyance)
• Valve
• Piping and plumbing fittings