Gate Valve Seat Seals Explained


Learn more about how ID and OD face seals are constructed to handle use out in the field.

The Inner Diameter (ID) face seals and Outer Diameter (OD) face seals used in type FLS and FLS-R slab gate valves are some of the most commonly replaced parts for these types of valves. The seals sit inside the grooves of the seat and seal onto the seat pockets on either side of the valve. They prevent any contaminants from entering the valve body which otherwise would cause damage and make for much more costly repairs.

Find out how ID and OD face seals are made so that they can handle the task of keeping contaminants out.

Face Seals for All Sizes of Valves

The first thing that should be considered is the size of the valve. FLS ID and OD face seals are used in all sizes of valves ranging from 1-13/16” to 7-1/16”. Regardless of size, both an ID and OD face seal are required on each seat in the valve. Heshka Oil has an extensive selection of ID and OD face seals for FLS and FLS-R style valves of all sizes.

Pressure Ratings for Face Seals

The next thing to look at is the pressure rating. Face seals from Heshka Oil have been qualified for pressures ranging from 5,000 PSI all the way to 22,500 PSI. A wide pressure range gives you peace of mind that when you install them in your equipment they’ll seal the first time.

Materials Used to Construct ID and OD Face Seals

In addition to the multiple sizes and pressures, ID and OD face seals can be made from various materials depending on the application that’s needed. Are you operating in conditions where there is H2S, CO2, brine, acids or other harsh media? Then you’ll need highly durable materials like Teflon. For other applications you may be able to use face seals made of more cost effective Glass Fiber Moly PTFE.

Heshka Oil has a material solution for any face seal application. Our face seal assemblies for the FLS series come standard with a Carbon Moly filled PTFE Jacket with a Cantilever Spring in either 300 Series Stainless or Elgiloy. We also have a proprietary blend of Teflon and PEEK materials that can be tailored to your operating conditions and can handle exposure to the harshest substances.

If your application is appropriate for Glass Fiber Moly PTFE we have these in stock and ready to ship as well.

ID and OD Face Seals in Repair Kits

ID and OD Face seals can be sold separately or in kits. Both types of face seals come in our major and minor repair kits for FLS and FLS-R style valves.

If you are looking for FLS Gate Valve ID and OD face seals for any type of application, you don’t need to look any further than Heshka Oil. We keep stock in all different sizes of ID and OD face seals because we know how important they can be to our customers' projects. Call us today to speak to one of our experienced sales reps or visit our website and buy them directly through

Save Time and Money - Buy ID and OD Face Seals Online!

Have questions about our ID or OD face seals? Want to know about other replacement parts for FLS and FLS-R style valves? The Heshka Oil blog has the answers about these parts and many more.

Posted On:

26th Feb 2022