In industries where safety, pressure, and temperature meet at extreme levels—like oil & gas, petrochemical, and offshore drilling—having a dependable sealing solution is not optional, it's essential. One of the most trusted and proven solutions in such high-demand environments is the API Ring Joint Gasket.
What is an API Ring Joint Gasket?
An API Ring Joint Gasket is a metal-to-metal sealing gasket designed specifically for use in high-pressure, high-temperature (HPHT) systems. These gaskets are precision-machined from solid metal and are used in conjunction with RTJ flanges. Their primary job is to form a tight, leak-proof seal between flanges, which is especially critical in fluid and gas pipelines.
What makes these gaskets stand out is their ability to deform slightly under pressure—just enough to create a solid metal seal, without compromising strength. This plastic deformation is the key to their efficiency: it ensures that the gasket fits perfectly into the flange groove and creates a seal that can withstand extreme operating conditions.
Types and Variants
API Ring Joint Gaskets come in a few standard shapes and pressure ratings:
R-Type: The basic and widely used type, available in oval or octagonal cross-section. Suitable for pressures up to 5,000 psi.

RX-Type: Designed to fit the same groove as R-type but provides improved sealing. Ideal for pressures up to 6,250 psi.

BX-Type: Specifically built for the most extreme conditions—up to 20,000 psi—offering enhanced pressure performance due to its pressure-energized design.

Each type is manufactured in line with strict standards such as API 6A and ASME B16.20, ensuring compatibility and safety across the industry.
Materials and Durability
Depending on the application, API gaskets are made from various metals, including:
Stainless Steel

Soft Iron

Inconel

Monel

Duplex and Super Duplex alloys

These materials are selected based on chemical compatibility, pressure levels, and the type of fluid or gas being handled. The durability and resistance of these materials allow API gaskets to function over long periods without the risk of failure—minimizing downtime and enhancing operational safety.
Where Are They Used?
API Ring Joint Gaskets are primarily found in:
Oil & gas exploration rigs

Refineries

Petrochemical plants

Power plants

Subsea pipelines

Valve connections in high-pressure systems

Their ability to handle fluctuating pressures and temperatures makes them essential in any system where sealing failure can lead to dangerous consequences.