How to Select Pipe Flanges for Steel Water Pipes

Pipe flanges are mechanical components used to close, connect, cover, or support pipes and pipeline systems.

Choosing the right flange for your project depends upon the application, pressure rating, and the pipeline material to ensure reliable performance, prevent leakage, and maintain performance.

Application

Ring Flanges

Ring flanges are a type of slip-on flange that slides over the end of a pipe and welded into place. These are the most common waterworks application flange for low pressure situations.

Blind Flanges

Blind flanges are used to seal off a piping system. Blind flanges block the flow of fluid and have no opening.

Pressure

The pressure rating specifies the maximum amount of pressure the flange can withstand without leakage or failure. Therefore, it is vital to ensure a flange pressure rating exceeds the system’s maximum output to prevent rupture.

Material

Flange material selection can be based on pressure, sustainability, or versatility of the matching piping system. Carbon steel is a cost-effective option for moderate temperatures and pressures. Stainless steel is preferred for environments requiring corrosion resistance applications. Stainless steel flanges are more durable and have a longer lifespan compared to the economical options of carbon steel.

Industry Standards

Pipe flange specifications are set by associations and industry standards to ensure the safety and reliability of a pipeline system. The frameworks provided by the association outline the dimensions, pressure tolerance, and design criteria. Common industry guidelines used for flanges include AWWA, ANSI, and ASME.