When ordering pipe flanges and parts, it’s best to be as specific as you can. Include details such as:
These details are key to ordering the correct pipe flanges. If you’re replacing an existing flange, refer to the specifications stamped on the existing flange. Otherwise, you will need to provide some or all of the following details when you submit your order request.
What connection type do you require? Most pipe connection types are intended for specific jobs and may not be interchangeable. Specify your connection method or the intended application for the flanges you are purchasing.
The most common flange connection types are:
Measure the outside diameter (O.D.)—across the flange from one outside edge to the other. Then, measure the center hole of the flange—the inside diameter (I.D.)—which correlates with the pipe size.
Know the number of bolt holes necessary, as well as the bolt circle diameter—measured from the center of one bolt hole to the center of the bolt hole directly across from it. If you are using a reducing flange to connect a larger pipe with a smaller pipe, you will need pipe diameter measurements for both pipes you wish to connect. Consider dimensional tolerances to determine permissible limits in measurement differences.
Flanges aren’t selected by physical measurements alone. The required pressure class or pressure-temperature rating helps determine which flanges are required.
Pressure class and measurements can be related: The higher the class, the larger the outside diameter and bolt holes. The thickness of the flange also increases as size and pressure rating go up. It may be acceptable to choose a flange with a higher pressure rating (but not a lower one), as long as the other flange dimensions and specifications match.
Explore our catalog and contact us with questions or to submit an order or inquiry—we’re available to help answer your questions, help you decide which flanges are appropriate, or provide a quote for your order.
For more information about ordering flanges and pipe system components, explore our Resource Center.