The Ring Type Joint, or RTJ, is the type of gasket required for the flange. The Ring Type Joint was created for the petroleum and petrochemical sectors, where greater pressures and temperatures exist. The sealing surface is a high tolerance groove carved into the face of the Flange, having a maximum finish of 63 RMS. When the bolts are torqued down, the RTJ ring compresses into the groove of the flanges, forming a seal.

It is always advised that the gasket material be softer than the mating flange. RTJ gaskets are available in various materials, including soft iron, low carbon steel, stainless steel, titanium, Hastelloy, and super duplex.

The three-ring type Joint Gasket designs are R Type, RX Type, and BX Type. The R Type is the most often used and comes with two distinct profiles: oval or octagonal. The oval type was the original design, including an oval-shaped groove machined into the Flange Face.

UKL Ring Joint Gasket (RTJ) creates a robust and long-lasting metal-to-metal seal between two mating RTJ flanges. As the flanges are bolted together, the softer material of the ring joint gasket is "squeezed" into the flange grooves (which are formed of a more complex substance), sealing the connection firmly.

When the metal is suitably selected, RTJ gaskets can tolerate strong chemicals and temperatures up to 1,000°C (1,832°F). All gaskets have a thin protective layer to prevent oxidation from air contact.

The ring joint gasket is a solid metal gasket with an oval cross-section manufactured from metal materials by forging, heat treatment, and machining. It is a conventional R-type metal ring gasket with radial self-tightening sealing properties.