Buying Guide to Stainless Steel Flanges


A flange is a cast ring that is designed to connect sections of a pipe or any other machinery that requires a connecting joint.  Before buying flanges, it is important to note that these flanges come in different materials, types/forms, sizes, diameters, and measurements.

Different types of Flanges are available for different types of applications. All you need to do is choose your product based on the project. When it comes to which materials should be used in your applications the following factors come into play and therefore, some important aspects that need to be considered while buying stainless steel flanges are discussed in this article:-

How to choose the correct Stainless Steel Flanges

Firstly it is important to note the diameter of pipes to which the flanges will be connected. Also, knowing whether these pipes are seamless, welded, ERW, etc. would help to choose the required flanges. As for stainless steel pipe flanges, discs and rings that attach to pipe in order to increase support or strength. These are generally screwed or welded to the pipe end. These pipes flanges are designed according to specifications and could be customized by manufactures.

Choose Flanges Based On Design of the Project

SS Flanges are accessible in numerous grades. The client’s selection of products should rely upon your budget and project need. Although top-quality products may be costly, they are indeed extremely sturdy. Both SS 304L Flanges and SS 316L Flanges are iron alloys having a very high, around 95 percent of alloy composition. SS 304 and SS 316 belong to the chromium-nickel category and are grades that withstand standard corrosion, are sturdy, resists most chemicals and holds greater resistance to numerous types of deterioration. Stainless steel 317 Flanges are hardened matching, low carbon with high additions of chromium and nickel. Stainless steel 347 Flanges should be considered for applications requiring intermittent heating between 800 degrees F (427 degrees C) and 1650 degrees F (899 degrees C).

Selection of Various Types of SS Flanges Available In Market:

SS Slip-on Flanges

The bore size of a slip-on flange is larger than the outside diameter of the connecting pipe, as the pipe has to slide inside the flange to be connected by the execution of a fillet weld. Applied in applications engaging in low pressure. When cost or space is an issue, this type is used instead of a weld neck.

SS Weld Neck Flanges

SS Weld Neck Flanges is used in high-pressure and high/low temperatures applications that require an unrestricted flow of the fluid conveyed by the piping system (the bore of the flange matches with the bore of the pipe).

SS Blind Flanges

Ideal for the piping system, requiring regular inspection. Handling high stress caused due to internal pressure and pressure of the liquid flowing through the pipe. Used to ‘blank off’ pipelines, valves, etc.

SS Threaded Flanges

Assembled without welding and hence, can be removed easily. Not necessarily used for applications where bending stresses, involving high temperature or pressure. A seal weld is used in conjunction with times. To make it cost-effective, this could be supplied without a hub, or in treated coated carbon steel.

SS Lap Joint Flanges

A type of slip-on flange. Helps in the maintenance of low alloy steel/ carbon pipes. These flanges are seen to be very similar to slip-on flanges but are characterized by the rounded interior edge of the flange face.

SS Socket -Weld Flanges

Smaller diameter handling applications with high pressure such as steam lines. Possess internal welds, ensuring durability. The bore of the pipe and the flange match thus providing, good flow connection.

SS Orifice Flanges

To provide access to a line for metering liquids or gases. The range of SS orifice flanges covers all standard sizes and range and is common to all flange materials.

SS Forged Flanges

Helps combine two machinery parts together making objects stronger, providing easy access for cleaning, inspecting and modifying. Types vary according to their use. Used mainly in high-pressure applications.