Isolation Kits for Bolts: The Gasket Isn't the Only Thing Doing the Isolating, and That's the Problem
A flange gasket may be the most visible insulating component in a connection, but it is not working alone. Bolts, washers and sleeves can create conductive paths if the full assembly is not isolated correctly. At Step-Ko Products, we build isolation kits for bolts around the complete connection rather than treating the gasket as the entire solution. Electrical isolation depends on preventing metal-to-metal contact across the joint.
Why Isolation Kits for Bolts Matter Beyond Gaskets
Step-Ko flange isolation gasket kits include gaskets, sleeves and washers. The gasket separates the flange faces while sleeves help keep bolts from contacting the flange bore. Insulating washers separate metallic hardware at the bolt ends.
If one path is overlooked, the connection may lose the electrical separation the gasket was selected to provide.
The Bolt Path Deserves Equal Technical Attention
A flange connection depends on metallic fasteners for clamping force. A gasket can separate flange faces, yet conductive contact through the hardware can work against that separation.
Step-Ko kits are designed to eliminate metal-to-metal contact and halt static current between flanges while supporting cathodic protection.
The complete assembly addresses three areas:
·The gasket separates and seals flange faces
·Sleeves isolate bolts through the flange holes
·Insulating washers separate hardware from flange surfaces
How Flange Bolt Insulation Kits Break Conductive Paths
Flange bolt insulation kits keep necessary fasteners from becoming an unintended electrical bridge across an isolated joint. Step-Ko uses insulating materials with high dielectric properties and low water absorption in its kits to support electrical separation and sealing.
Selection should therefore go beyond gasket type. Bolt arrangement, flange configuration and the matching sleeve and washer components all matter.
Different Gasket Styles Change The Isolation Picture
Step-Ko offers Type D, Type E, Type F and Warrior gasket configurations. Type D fits the ring groove of RTJ flanges. Type E is a full-face gasket with the same outside diameter as the flanges. Type F fits the raised face area inside the bolt circle. Warrior gaskets add sealing elements and are offered in Type E and Type F styles.
Flange bolt insulation kits make the most sense when sleeve washers and gasket type are specified as a coordinated assembly.
Foreign Material Can Shorten Electrical Isolation Performance
Step-Ko notes that foreign material can create a bridge across an isolated flange. Type E gaskets help reduce this concern through their full-face design. With Type F gaskets, Step-Ko recommends flange band protectors to help prevent foreign material from collecting and shortening cathodic isolation.
The connection must continue to avoid conductive bridging after the components are assembled.
Put The Whole Flange Connection Under Review
At Step-Ko Products, we treat sealing and electrical separation as connected requirements. Our flange isolation gasket kits are available from 1/2 inch through 144 inches across ANSI and API classes, with custom and special sizes available.
If you are specifying or replacing an isolation kits for bolts assembly, talk with our team about the complete joint. We can review the flange size, gasket style and matching insulating components so the gasket sleeves and washers are considered together rather than as unrelated parts. A complete specification keeps the isolation approach centered on the connection as a whole and helps avoid overlooking the bolt-side components during product selection and installation planning.
Frequently Asked Questions
1: What Parts Are Included In A Flange Isolation Kit?
Step-Ko kits include gasket sleeves and washers. These components work together to support sealing and reduce metal-to-metal contact across the flange.
2: Why Are Bolt Sleeves Used In Isolation Kits?
Sleeves help keep metallic bolts from contacting conductive flange surfaces through the bolt holes and support electrical separation across the joint.
3: What Do Insulating Washers Do On Flange Bolts?
Insulating washers separate metallic bolt hardware from the flange surface and work with the gasket and sleeve to limit conductive contact.
4: Are Flange Bolt Insulation Kits Only About Corrosion?
No. Step-Ko positions flange bolt insulation kits around electrical isolation, sealing support and cathodic protection rather than treating corrosion control as a gasket-only function.
5: Can One Isolation Kit Fit Every Flange Connection?
No. Step-Ko offers multiple gasket types, sizes and ANSI or API classes. Selection depends on the actual flange configuration and application requirements.
