Ring Type Joint Flange
A Ring Type Joint Flange is a type of flange that uses a metal ring that sits in a hexagonal groove as a gasket to seal the flange pair. The flanges seal when the bolts are tightened and the gasket is compressed into the groove making a metal to metal seal. An RTJ flange usually has a raised face with the groove machined into the face of the flange. The raised face doesn’t serve as a way to contain the pressure.
RTJ Flanges are used for high pressure applications up to pressures as high as 15,000 psi (103 MPa). It is only furnished only on steel or alloy valve bodies and usually need to specified when ordering. The flanges usually come in blind, slip-on, threaded and weld neck.
The benefits of using an RTJ flange and ring is that the gasket is confined to a groove and has two sealing surfaces. The groove assures that the ring centers itself when the bolts are tightened. It also is self actuating meaning that the sealing pressure increases when the process pressure increases.
The disadvantages of using RTJ Flanges is that ring type joint grooves can accumulate dirt or moisture when the flange is open. Since the seal is a metal on metal connection, a small amount of damage on the narrow sealing surface(s) may lead to a leak. Additionally, the grooves and gasket must align properly in order to assemble the flange and obtain a seal. They must stay aligned throughout the operating cycle. This is important if you are flanging up to dissimilar metals like stainless steel to carbon steel flanges.
Description of Ring Type Joint Flange
- ANSI, MSS, API, AWWA, DIN, JIS, BS and GB.
- from 150lbs to 2,500lbs.
- From 1/2″ to 84″.
- Carbon steel, stainless steel and alloy steel.
- Carbon steel and alloy steel with yellow print, black print, oil or zinc.
- Plywooden case.
- Usage: Oil Field, Offshore, Water System, Shipbuilding, Natural Gas, Electric Power, Pipe Projects, etc.
- NICKEL – Nickel 200/201.
- INCONEL – Inconel 600, Inconel 601, Inconel 617, Inconel 690, Inconel 690, Inconel 713C, Inconel 718, Inconel X-750, Inconel
X-751, Inconel 800, Inconel 800H, Inconel800HT, Incone825, Inconel 890, Inconel 925, Inconel SX300.
- HASTELLOY – Hastelloy C-276, Hastelloy C-22, Hastelloy C-2000, Hastelloy-X, Hastelloy B-2, Hastelloy B-3, Hastelloy
C-4, Hastelloy G-30, Hastelloy G-35, Hastelloy N.
- MONEL – Monel 400, Monel K-500.
- DUPLEX & SUPER DUPLEX – Duplex 2205, Duplex 2207, Duplex 31803, Super
Duplex 32750, Super Duplex 32760, Super Duplex 32550, 253MA, SMO 254, AL-6XN.
- TITANIUM – Titanium Gr.1, Titanium Gr.2, Titanium Gr.3, Titanium Gr.4, Titanium
Gr.5, Titanium Gr.7, Titanium Gr.11, Titanium Gr.12.
- NIMONIC – Nimonic 75, Nimonic 80A, Nimonic 81, Nimonic 90, Nimonic 105,
Nimonic 115, Nimonic 901.
- SPECIAL ALLOYS – Alloy 20, Alloy 286, Invar 36, Invar 42, Kovar, Stellite Gr.6,
Stellite Gr.25, Alloy 230, Alloy 28, Maraging Steel, Cobalt, Tantalum.
- STAINLESS STEEL – SS 303, SS 304, SS304L, SS310, SS316, SS316L, SS317, SS317L, SS321, SS347, SS 17-4PH, SS 15-5PH, SS 904L, XM-19, Nitronic 50, Nitronic 60.