Ring Type Joint Gasket (RTJ Gasket) Manufacturer, Supplier & Exporter
Jade Alloys is a precision manufacturer, supplier, and exporter of Ring Type Joint Gaskets (RTJ Gaskets) engineered for the most demanding high-pressure and high-temperature sealing applications across oil & gas, petrochemical, subsea, and power generation industries. Our ring joint gaskets comply to ASME B16.20 and API 6A standards and are manufactured in a wide variety of materials including stainless steel, duplex, super duplex, monel, inconel and hastelloy and in various profiles such as Type R (oval and octagonal), Type RX and Type BX.
All ring type joint gaskets made by us go through a strict dimension check and surface finish check to ensure the integrity of sealing between metal surfaces at pressures up to 20,000 psi, a performance which can’t be matched with traditional gasket solutions over the long-term.
Table of Contents
- ASTM F594 Stainless Steel Nuts Manufacturer & Supplier in India
- RTJ Gasket Types — Profiles, Pressure Classes & Standards
- Standard Stock Sizes of Plug Gaskets
- RTJ Gasket Materials — Grades, Hardness & Selection Guide
- Hardness Requirements per API 6A / ASME B16.20
- Detailed Material Pages
- Related Products
- RTJ Gasket Applications & Industries Served
- Manufacturing Standards & Certifications
- Why Choose Jade Alloys for RTJ Gaskets?
- Surface Finish Requirements for RTJ Gaskets
- Frequently Asked Questions — Plug Gaskets
What Is a Ring Type Joint Gasket (RTJ Gasket)?
A ring type joint gasket (RTJ gasket), also referred to as a ring joint gasket or RTJ flange gasket, is a solid metallic sealing element designed to be installed in machined grooves on mating flanges. When the flange bolts are tightened, the compressive axial load causes the ring gasket to plastically deform, forcing it to flow into the microscopic irregularities of the groove surface and creating a high-integrity metal-to-metal seal.
Unlike soft or semi-metallic gaskets, ring joint gaskets achieve sealing through controlled deformation rather than compressibility. Because the sealing load is concentrated over a very small contact area, surface stresses generated are significantly higher than the working pressure, making RTJ gaskets exceptionally effective at retaining high-pressure gases and fluids. This characteristic also means ring joint gaskets are single-use, the plastic deformation that creates the seal prevents reliable re-sealing on reuse.
RTJ Gasket Types — Profiles, Pressure Classes & Standards
Jade Alloys manufactures the full spectrum of ring type joint gasket profiles, each engineered for specific pressure classes and flange systems. Selecting the correct RTJ gasket type is critical to sealing performance, flange longevity, and system safety.
| Type | Profile | Pressure Class | Flange Standard | Notes |
|---|---|---|---|---|
| R Oval | Oval | ≤ 5,000 psi | API 6B / ASME B16.5 | Interchangeable with R Octagonal; soft-sealing |
| R Octagonal | Octagonal | ≤ 5,000 psi | API 6B / ASME B16.5 | Higher contact stress than oval; preferred for new installations |
| RX | Pressure-energized | ≤ 6,250 psi | API 6B / ASME B16.5 | Backward-compatible with R grooves; self-energizing under pressure |
| BX | Pressure-energized | Up to 20,000 psi | API 6BX | Non-interchangeable; pressure equalization hole; subsea & ultra-HP |
| SBX | Modified BX | Up to 20,000 psi | API 6BX | Special large-bore BX variant for subsea wellhead connectors |
Type R — Oval & Octagonal Ring Joint Gaskets
Type R ring gaskets are the most widely used RTJ profile in upstream and midstream oil & gas applications. Available in both oval and octagonal cross-sections, they are designed for ASME B16.5 and API 6B flanges operating up to 5,000 psi. Octagonal profiles offer a greater contact area and higher seating stress than oval profiles, making them the preferred choice for new installations. Both profiles are interchangeable within the same flange groove, providing flexibility during maintenance. Type R gaskets are manufactured per ASME B16.20 and API 6A with surface finishes of 63 µin Ra (1.6 µm Ra) maximum.
Type RX — Pressure-Energized Ring Joint Gaskets
Type RX ring gaskets feature a pressure-energized design where system pressure assists the sealing load, increasing sealing efficiency as operating pressure rises. RX gaskets are backward-compatible with standard R-type flange grooves and are rated to 6,250 psi per API 6A. They are an ideal upgrade for existing RTJ flange systems requiring enhanced sealing reliability without flange replacement. The RX profile is particularly suited for natural gas and hydrocarbon service where fugitive emissions compliance is essential.
Type BX — Ultra-High Pressure Ring Joint Gaskets
Type BX ring gaskets are engineered for the most extreme conditions: subsea wellheads, Christmas trees, blowout preventers, and other API 6BX flange systems rated up to 20,000 psi. BX gaskets incorporate a pressure-equalization hole that prevents hydraulic lock during assembly and equalizes pressure across both sealing faces, ensuring reliable make-up even in challenging offshore environments. BX gaskets are not interchangeable with R or RX grooves — dedicated API 6BX flanges with machined BX grooves are required. Surface finish requirements are more stringent at 32 µin Ra (0.8 µm Ra).
Standard Stock Sizes of Plug Gaskets
| OD (mm) | ID (mm) | Thickness (mm) | Plug Size (inch) | Availability |
|---|---|---|---|---|
| 27 | 21 | 2 | 7/8″ | Ready Stock |
| 36 | 30 | 2 | 1″ | Ready Stock |
| 42 | 36 | 2 | 1¼” | Ready Stock |
| 48 | 42 | 2 | 1½” | Ready Stock |
| Custom sizes | 20–80 | 1–5 | As required | 2–3 weeks lead time |
RTJ Gasket Materials — Grades, Hardness & Selection Guide
The choice of RTJ gasket material is the single most important factor in determining sealing performance and service life. Jade Alloys offers an extensive range of rtj gasket materials, each selected and tested to remain softer than the mating flange grooves — a fundamental requirement to ensure the gasket deforms under bolt load without damaging the flange. Per API 6A and ASME B16.20, gasket hardness must always be lower than the groove hardness to ensure the gasket — not the flange — yields during make-up.
| Material | Grade / Standard | Max BHN | Key Property |
|---|---|---|---|
| Soft Iron (Fe) | ASTM A105 / API 6A | 90 BHN | Low-pressure non-corrosive media |
| Low Carbon Steel | ASTM A105 | 120 BHN | General-purpose high-pressure |
| Stainless Steel 304 | ASTM A182 F304 | 160 BHN | Corrosion resistance, food & pharma |
| Stainless Steel 316 | ASTM A182 F316 | 160 BHN | Chloride & acid resistance |
| Stainless Steel 316L | ASTM A182 F316L | 160 BHN | Low-carbon weld-sensitive apps |
| Duplex Steel (UNS S31803) | ASTM A182 F51 | 220 BHN | High strength + corrosion resistance |
| Super Duplex (UNS S32750) | ASTM A182 F53 | 270 BHN | Seawater, offshore, aggressive media |
| Monel 400 (UNS N04400) | ASTM B164 | 150 BHN | Seawater, HF acid, alkalis |
| Inconel 625 (UNS N06625) | ASTM B446 | 220 BHN | Extreme heat & corrosion |
| Hastelloy C276 (UNS N10276) | ASTM B574 | 209 BHN | Highly corrosive chemical media |
Hardness Requirements per API 6A / ASME B16.20
| Gasket Material | Brinell Hardness (max) | Rockwell (max) | ID Mark |
|---|---|---|---|
| Soft Iron | 90 | 56 (HRB) | D |
| Low Carbon Steel | 120 | 68 (HRB) | S |
| 4-6% Cr / ½% Mo | 130 | 72 (HRB) | F5 |
| Stainless Steel 304 | 160 | 83 (HRB) | S304 |
| Stainless Steel 316 | 160 | 83 (HRB) | S316 |
| Stainless Steel 347 | 160 | 83 (HRB) | S347 |
Detailed material pages:
Stainless Steel RTJ Gaskets | SS 304 RTJ Gasket | SS 316 RTJ Gasket | Duplex Steel RTJ Gasket | Super Duplex RTJ Gasket | Soft Iron RTJ Gasket
Monel RTJ Gaskets | Inconel RTJ Gaskets | Hastelloy RTJ Gaskets
RTJ Gasket Applications & Industries Served
Ring type joint gaskets are specified wherever high-pressure, high-temperature, or zero-leak-tolerance sealing is mandatory. Jade Alloys supplies RTJ gaskets to the following industries:
Oil & Gas
- Wellhead assemblies, Christmas trees, and blowout preventers
- Pipeline flanges and manifold connections
- Oil refinery process piping (hydrocrackers, reformers, FCC units)
- Subsea and deepwater production equipment
Petrochemical & Chemical Processing
- High-pressure reactor vessel flanges
- Heat exchanger flange connections
- Sealing joints in storage tank nozzles
- Aggressive chemical media requiring Hastelloy or Monel RTJ gaskets
Power Generation
- High-pressure steam turbine flanges
- Boiler feed pump casing joints
- Supercritical and ultra-supercritical boiler systems
Marine & Offshore
- Seawater injection system flanges
- Subsea pipeline connectors and risers
- Ship engine high-pressure fuel and lubrication systems
Mining & Heavy Industry
- Slurry pump flanges
- High-pressure hydraulic system connections
- Process plant piping in aggressive environments
Manufacturing Standards & Certifications
All Jade Alloys ring type joint gaskets are manufactured, tested, and documented in accordance with the following international standards:
- ASME B16.20 — Metallic Gaskets for Pipe Flanges (primary dimensional and material standard)
- API 6A — Wellhead and Christmas Tree Equipment
- API 6B — Flanges for Wellhead and Christmas Tree Equipment
- API 6BX — Type 6BX Flanges for High-Pressure/High-Temperature Service
- NACE MR0175 / ISO 15156 — Sour service material requirements (H₂S environments)
- PED 2014/68/EU — European Pressure Equipment Directive (for export to EU markets)
Why Choose Jade Alloys for RTJ Gaskets?
- Precision machining: dimensional tolerances held to ASME B16.20 and API 6A requirements on every batch
- Full material traceability: mill test reports (MTRs) and material certificates supplied with every order
- In-house hardness testing to verify each gasket is softer than the corresponding flange groove specification
- Surface finish verification: profilometer-measured Ra values documented on inspection records
- Wide alloy range: carbon steel, stainless steel, duplex, super duplex, Monel, Inconel, Hastelloy and more
- Anti-corrosion protection: electrolytic zinc (yellow chromate) plating available to 0.0003″ thickness per API 6A
- Custom sizes and non-standard profiles manufactured to customer drawings
- Fast lead times with air freight options for urgent shutdowns and turnarounds
- Export packing with moisture-absorbing desiccant and individual gasket tagging for easy on-site identification
Surface Finish Requirements for RTJ Gaskets
Surface finish is critical to RTJ gasket sealing performance. Jade Alloys machines all ring joint gaskets to the following maximum surface roughness values, verified by calibrated profilometers:
- Type R Oval and R Octagonal: 63 µin Ra (1.6 µm Ra) maximum
- Type RX (Pressure-Energized): 63 µin Ra (1.6 µm Ra) maximum
- Type BX (Ultra-High Pressure): 32 µin Ra (0.8 µm Ra) maximum
All sealing faces are inspected to be free from indentations, tool marks, radial scratches, pits, and other surface defects that could compromise the metal-to-metal seal.
Frequently Asked Questions — Plug Gaskets
What is a ring type joint gasket (RTJ gasket)?
A ring type joint (RTJ) gasket is a solid metallic sealing element installed in precision-machined grooves on RTJ flanges. Under bolt load it plastically deforms to fill groove surface irregularities, forming a high-integrity metal-to-metal seal capable of holding pressures up to 20,000 psi. RTJ gaskets are used wherever conventional soft or semi-metallic gaskets would fail — primarily in oil & gas, petrochemical, and subsea applications.
What are the different types of RTJ gaskets?
The three main types are: Type R (oval or octagonal) for pressures up to 5,000 psi used with API 6B and ASME B16.5 flanges; Type RX (pressure-energized) compatible with R-type grooves rated to 6,250 psi; and Type BX (ultra-high pressure) for API 6BX flanges up to 20,000 psi. Jade Alloys also manufactures SBX type gaskets for special large-bore subsea connectors.
What is the best RTJ gasket material for sour gas service?
For H₂S-containing (sour) environments, soft iron and low-carbon steel RTJ gaskets meeting NACE MR0175 / ISO 15156 are standard. For higher corrosion resistance, Stainless Steel 316 or duplex steel RTJ gaskets are preferred. Inconel 625 and Hastelloy C276 are used where both sour conditions and highly corrosive media are present. Jade Alloys can supply NACE-compliant RTJ gaskets with full material certification.
Are RTJ gaskets interchangeable between types?
Type R oval and R octagonal gaskets are interchangeable within the same flange groove. Type RX gaskets are backward-compatible with R-type grooves. Type BX gaskets are NOT interchangeable — they require dedicated API 6BX flange grooves and must not be substituted with R or RX types.
Can ring joint gaskets be reused?
No. RTJ gaskets seal through plastic deformation — the gasket permanently yields to the flange groove during first make-up. Reusing a ring joint gasket is a serious safety risk as it cannot provide a reliable seal on reassembly. Always install a new gasket when opening an RTJ flange joint.
What standards govern RTJ gasket manufacturing?
RTJ gaskets are primarily manufactured to ASME B16.20 and API 6A. Flange compatibility follows API 6B for R and RX types and API 6BX for BX types. For sour service applications, NACE MR0175 / ISO 15156 material requirements apply. Jade Alloys supplies full material test reports and dimensional inspection records with every order.
How do I get a price for Plug Gaskets?
Contact us via the quote form below, by email at sales@jadealloys.com or by phone at +91 9987685906. Please provide the material, OD, ID, thickness, quantity and any coating requirement. We respond with a competitive price within 24 hours.
