What Is a Ring Gasket?

A ring gasket is a metal sealing ring used in high-pressure flange connections in oil and gas systems. In most cases, technicians install it in Ring Type Joint (RTJ) flanges to create a strong, reliable, and high-integrity seal.

Material Types

Manufacturers produce ring gaskets from different metals to match service conditions.
For example:

• Carbon Steel: Used in general service where corrosion risk stays low.
• Stainless Steel (304 / 316): Used when corrosion resistance becomes important.
• Alloy Steel: Used in higher temperature and higher pressure service.
• Special alloys (Inconel, Monel): Used in highly corrosive or extreme environments.

How It Works

First, technicians place the ring gasket into the machined RTJ groove on the flange face.
Next, they align the mating flange and install the bolts. Then, as they tighten the bolts, the gasket begins to deform slightly. As a result, it conforms tightly to the groove profile.
Finally, this controlled deformation creates a strong, leak-tight metal-to-metal seal.

RTJ Groove Function

The gasket seats inside a machined RTJ groove. In addition, this groove controls the compression and ensures the gasket stays centered during assembly. Therefore, the groove plays a critical role in achieving a reliable seal under high pressure.

Types of Ring Gaskets

• Oval RTJ: Used in traditional flange designs and legacy systems.
• Octagonal RTJ: Used in modern systems because it improves sealing efficiency.

Typical Applications

• First of all, high-pressure oil and gas production systems
• In addition, wellheads and Christmas trees
• Furthermore, subsea piping systems
• Also, high-temperature process piping
• Finally, refinery and petrochemical critical flange connections

Advantages

• To begin with, ring gaskets handle extremely high pressure and temperature conditions
• In addition, they provide excellent sealing integrity in critical service
• Furthermore, they resist extrusion under heavy flange loading
• Finally, they perform reliably in harsh operating environments when material selection is correct

Limitations

• They require precisely machined RTJ grooves
• They cost more than soft gasket options
• They do not tolerate flange face damage or misalignment well
• They require careful installation to achieve proper sealing

Summary

In summary, a ring gasket is a metal sealing ring, typically made from steel or stainless steel, that technicians install into an RTJ groove in a flange. Therefore, it forms a highly reliable seal in demanding oil and gas applications where pressure and temperature exceed the limits of
soft gasket materials.