Ring Type Joint Gaskets

Ring Type Joint (RTJ) Gaskets: High-Pressure Flange Seals

Arabian Gulf supplies premium Ring Type Joint (RTJ) gaskets in R (oval/octagonal), RX, and BX styles, manufactured from low-carbon mild steel, Stainless Steel 304 (1.4301), and Stainless Steel 316 (1.4401) for sour service compliance (NACE MR0175). These metal-to-metal seals deliver zero leakage at pressures up to 20,000 psi (138 MPa) and temperatures from -46°C to 400°C, conforming to API 6A PSL 2-4, ASME B16.20, and ASTM A105/A182 specifications.

In addition to standard RTJ gaskets, Arabian Gulf stocks valve test gaskets in urethane-coated and rubber-coated (HNBR) configurations for low-pressure hydrostatic testing (up to 1,500 psi). Our premium BoKure™ urethane RTJ gaskets (RTJU) provide corrosion protection and reusability for high-cycle applications, while rubber-coated variants offer enhanced conformability on imperfect flange faces.

RTJ Gasket Styles and Applications

StyleProfilePressure Rating (psi)Seating TypeTypical Applications
R OvalOval ring5,000-10,000Initial soft seatStandard wellhead flanges
R OctagonalOctagonal ring10,000-20,000Metal-to-metalHigh-pressure API 6A flanges
RXRX profile10,000-15,000Energized taperReplacement for R in worn grooves
BXBX profile15,000-20,000Parallel taperSubsea/high-temp wellheads

Material Specifications

MaterialYield Strength (ksi)Hardness (HB)Temp Limit (°C)H2S ServiceCorrosion Resistance
Soft Iron/Mild Steel30-40120-150425NoFair
SS 304 (A182 F304)30 min140-190540YesGood
SS 316 (A182 F316)25 min140-190540YesExcellent
BoKure™ UrethaneN/A85 Shore D120LimitedSuperior

Standard Dimensions Table – R Style (ASME B16.20/API 6A, inches)

ASME Class/SizeR Oval ID x OD x CSR Octagonal ID x OD x CS
900# 2″1.88 × 3.01 × 0.1801.88 × 3.01 × 0.207
1500# 3″2.88 × 4.25 × 0.2372.88 × 4.25 × 0.275
2500# 4-1/16″3.78 × 5.43 × 0.3173.78 × 5.43 × 0.366
5000# 4-1/16″3.78 × 6.00 × 0.5303.78 × 6.00 × 0.612
10000# 7-1/16″6.38 × 9.81 × 0.8116.38 × 9.81 × 0.937

RX/BX Dimensions Selection Guide (API 6A)

Flange Size (inches)RX Ring No.BX Ring No.Cross Section (inches)Pressure Rating (psi)
2-1/16RX 44BX 1550.2505,000
4-1/16RX 66BX 1770.37510,000
7-1/16RX 88BX 1990.50015,000
11RX 110BX 2110.62510,000

Valve Test Gaskets and Specialty Coatings

TypeMaterial/CoatingTest Pressure (psi)ReusabilityApplications
Urethane CoatedUrethane on steel1,5005+ cyclesGate valve body tests
Rubber CoatedHNBR on steel1,0003-5 cyclesCheck valve pressure tests
BoKure™ RTJUPure urethane75010+ cyclesNon-metallic RTJ replacement

RTJ gaskets feature precision-machined profiles ensuring 100% metal-to-metal contact, with dimensional tolerances ±0.005″ on critical seating surfaces. BX styles provide superior extrusion resistance (up to 30% higher contact stress) for subsea and HP/HT environments.