When should you use ring-type joint (rtj) seal?

Class 900 and above flanged connections, and lower classes where the specification mandates RTJ for high-integrity service High-temperature, high-pressure hydrocarbon and refinery service where a spiral-wound gasket's soft filler is a weak point

Sealing & Emission Control Systems

Body / Joint Sealing

Ring-Type Joint (RTJ) Seal

A solid metal ring (octagonal or oval) seats into matching grooves machined into the flange faces, giving metal-to-metal sealing for the highest pressure classes and most demanding services - no soft filler to age or extrude.

How does ring-type joint (rtj) seal work?

Bolt load forces the metal ring to yield slightly into the groove profile on both flange faces, creating a metal-to-metal seal with no reliance on a compressible filler - the ring itself is treated as a one-time-use consumable, replaced at every joint break.

When to Use It

Class 900 and above flanged connections, and lower classes where the specification mandates RTJ for high-integrity service
High-temperature, high-pressure hydrocarbon and refinery service where a spiral-wound gasket's soft filler is a weak point

Limitations

Requires precision-machined grooved flanges (RTJ-specific flange facing) - cannot retrofit onto a raised-face flange without changing the flange itself
The ring is single-use; reusing a compressed RTJ ring is a known cause of joint leakage

Typical MaterialsSoft iron; stainless steel; Inconel (for high-temperature or corrosive service)

Used OnGate Valves Globe Valves Check Valves