NORSOK IX Seal Ring Gaskets | Compact Flange Metal Seal Rings

NORSOK IX seal ring gaskets are high-integrity metal sealing rings designed for compact flange connections in offshore, subsea and high-pressure piping systems.

The IX-rings are designed and used where the NORSOK CFC (Compact Flange Connections) are in use. The rings come in three different kinds of steel and are coated with PTFE in varying colours in order to distinguish between them. Standard identification NORSOK STANDARD L-005 (NCF5). All markings should be on the inside of the ring.

Manufactured according to:

  • NORSOK L-005
  • ISO 27509

IX seal rings provide:

  • reliable metal-to-metal sealing
  • high-pressure sealing integrity
  • superior fatigue resistance
  • excellent corrosion resistance

      We are a professional manufacturer and exporter of:

      • NORSOK IX Seal Ring Gaskets
      • Compact Flange Seal Rings
      • ISO 27509 Seal Rings
      • Metal Seal Rings
      • Offshore Compact Flange Gaskets

      in China.


      What is a NORSOK IX Seal Ring Gasket?

      A NORSOK IX seal ring gasket is a precision-machined metal sealing ring designed for compact flange systems used in critical offshore and high-pressure applications.

      The IX seal ring creates:

      • metal-to-metal sealing
      • dual sealing action
      • pressure-energized sealing performance

      Unlike conventional soft gaskets, IX seal rings rely on:

      • elastic deformation
      • axial preload
      • radial sealing force

      to achieve:

      • leak-tight sealing
      • high-integrity pressure containment

      IX seal rings are specifically developed for:

      • offshore compact flange systems
      • subsea piping systems
      • high-pressure transmission lines

      NORSOK L-005 Standard

      NORSOK L-005 is the Norwegian offshore standard covering:

      • compact flange connections
      • seal ring geometry
      • flange sealing systems
      • offshore piping systems

      The standard defines:

      • sealing dimensions
      • preload requirements
      • material compatibility
      • inspection requirements

      NORSOK compact flange systems are widely used in:

      • North Sea offshore projects
      • subsea oil & gas systems
      • offshore production facilities

      ISO 27509 Compact Flange Standard

      ISO 27509 is the international standard for:

      • compact flange systems
      • metal seal ring connections
      • high-integrity flange sealing systems

      The standard harmonizes compact flange design requirements for global offshore projects.


      How IX Seal Rings Work

      IX seal rings operate through:

      • axial bolt preload
      • elastic compression
      • radial sealing force

      During flange assembly:

      • bolt load compresses the seal ring
      • sealing force is transferred into radial pressure
      • compact flange faces achieve metal-to-metal contact

      The system creates:

      • primary seal at the flange heel
      • secondary seal at the IX seal ring

      This dual sealing mechanism improves:

      • leak prevention
      • operational reliability
      • offshore safety performance

      Advantages of NORSOK IX Seal Ring Gaskets

      High Integrity Sealing

      Designed for:

      • critical offshore systems
      • high-pressure piping
      • subsea production equipment

      Excellent Pressure Resistance

      Suitable for:

      • HPHT applications
      • offshore manifolds
      • subsea pipelines

      Superior Corrosion Resistance

      Available in:

      • Inconel 625
      • Duplex stainless steel
      • Super Duplex alloys

      Improved Fatigue Resistance

      Ideal for:

      • offshore vibration service
      • dynamic loading conditions
      • subsea systems

      Reduced Leakage Risk

      The pressure-energized design improves:

      • sealing reliability
      • long-term integrity
      • environmental safety

      NORSOK IX Seal Ring Specifications

      Specification Details
      Product Type IX Seal Ring Gasket
      Standard NORSOK L-005 / ISO 27509
      Seal Type Metal-to-Metal Seal
      Application Compact Flange System
      Service Offshore / Subsea / High Pressure
      Design High Integrity Seal Ring

      NORSOK-IX-SEALING-RING-DIMENSION

      NORSOK-IX-SEALING-RING-DIMENSION

      DN NPS IX size DG1 mm DG2 mm DG3 mm DG4 mm DG5 mm DG6 mm DG7 mm DG8 mm HG1 mm HG2 mm HG3 mm HG4 mm HG5 mm RG1 mm Weight kg
      15 1/2 IX15 22.2 27.91 28.46 28.66 27.47 29.14 30.19 24.7 0.35 1.2 3.3 3.8 10 0.5 0.02
      20 3/4 IX20 27.2 32.93 33.47 33.67 32.48 34.16 35.2 29.7 0.35 1.2 3.3 3.8 10 0.5 0.03
      25 1 IX25 34.2 39.95 40.49 40.69 39.5 41.18 42.22 36.7 0.35 1.2 3.3 3.8 10 0.5 0.03
      40 1 1/2 IX40 49.3 55.84 56.38 56.58 55.34 57.11 58.21 51.9 0.35 1.27 3.48 4 10.56 0.5 0.05
      50 2 IX50 61.3 68.43 69.08 69.32 67.92 69.89 71.13 64.4 0.42 1.41 3.89 4.5 11.78 0.6 0.08
      65 2 1/2 IX65 74.4 82.14 82.79 83.03 81.52 83.69 85.05 77.8 0.42 1.56 4.28 4.9 12.98 0.6 0.12
      80 3 IX80 89.5 97.74 98.49 98.77 97.09 99.47 100.96 93.3 0.49 1.71 4.7 5.4 14.24 0.7 0.17
      100 4 IX100 115.7 125.17 126.04 126.36 124.44 127.15 128.85 120.1 0.56 1.94 5.34 6.2 16.19 0.8 0.28
      125 5 IX125 142 152.66 153.64 154 151.87 154.87 156.75 146.7 0.63 2.15 5.92 6.8 17.94 0.9 0.42
      150 6 IX150 170.2 182.17 183.25 183.66 181.32 184.61 186.66 175.4 0.7 2.36 6.48 7.5 19.64 1 0.62
      200 8 IX200 220.5 233.46 234.66 235.1 232.45 236.19 238.54 226.5 0.77 2.68 7.38 8.5 22.36 1.1 0.99
      250 10 IX250 274.9 292.64 294.05 294.57 291.57 295.78 298.42 281.7 0.91 3.02 8.31 9.6 25.2 1.3 1.85
      300 12 IX300 325 341.13 342.65 343.21 339.97 344.52 347.36 332.5 0.98 3.26 8.96 10.4 27.15 1.4 2.18
      350 14 IX350 357.1 373.87 375.38 375.94 372.58 377.34 380.32 365 0.98 3.42 9.39 11 28.46 1.4 2.6
      400 16 IX400 409.3 427.36 428.98 429.58 425.98 431.08 434.27 417.9 1.05 3.66 10.05 11.9 30.47 1.5 3.43

      Available Materials for IX Seal Rings

      Inconel 625 (UNS N06625)

      Duplex Stainless Steel UNS S32205

      Super Duplex Stainless Steel UNS S32750

      AISI 4130

      AISI 4140


      Corrosion Resistant Coating

      IX seal rings are often supplied with:

      • PTFE coating
      • anti-galling coating
      • corrosion-resistant surface treatment

      PTFE coating provides:

      • improved corrosion resistance
      • easier installation
      • reduced galling risk
      • visual identification

      Pressure Ratings of IX Seal Rings

      NORSOK IX seal ring gaskets are commonly used for:

      • high-pressure compact flange systems

      Available Pressure Classes

      • Class 150
      • Class 300
      • Class 600
      • Class 900
      • Class 1500
      • Class 2500

      Available PN Ratings

      • PN50
      • PN260
      • PN420

      Pressure capability depends on:

      • flange design
      • material grade
      • operating temperature

      Compact Flange Applications

      IX seal rings are specifically designed for:

      • compact flange systems
      • NORSOK flange connections
      • ISO 27509 flange systems

      Compact flanges provide:

      • reduced flange size
      • lower system weight
      • improved sealing integrity

      making them ideal for:

      • offshore installations
      • subsea applications
      • weight-sensitive projects

      IX Seal Ring vs RTJ Gasket

      Property IX Seal Ring RTJ Gasket
      Flange Type Compact Flange RTJ Flange
      Sealing Mechanism Metal Compact Seal Ring Joint
      Offshore Use Excellent Good
      Weight Reduction Better Standard
      Fatigue Resistance Higher Moderate

      IX seal rings are preferred for:

      • offshore compact flange systems
      • subsea piping
      • high-integrity sealing applications

      Manufacturing Process of IX Seal Rings

      Typical manufacturing process includes:

      • forging
      • CNC machining
      • precision profiling
      • coating application
      • dimensional inspection
      • surface inspection

      Strict quality control ensures:

      • sealing profile accuracy
      • dimensional precision
      • reliable sealing performance

      Inspection and Testing

      IX seal rings may undergo:

      • dimensional inspection
      • visual inspection
      • PMI testing
      • hardness testing
      • material verification

      Optional third-party inspection:

      • DNV
      • BV
      • ABS
      • SGS
      • TUV

      Products can be supplied with:

      • EN 10204 3.1 certificates
      • full material traceability

      NACE MR0175 Compliance

      IX seal ring gaskets can be manufactured according to:

      • NACE MR0175
      • ISO 15156
      • offshore sour service requirements

      Suitable for:

      • H₂S environments
      • sour gas pipelines
      • offshore production systems

      Applications of NORSOK IX Seal Ring Gaskets

      Offshore Oil & Gas Platforms

      Used in:

      • topside piping systems
      • compact flange connections
      • process piping

      Subsea Systems

      Applied in:

      • subsea manifolds
      • subsea connectors
      • subsea pipelines

      FPSO Systems

      Suitable for:

      • compact piping layouts
      • high-integrity flange systems

      High Pressure Pipelines

      Used in:

      • gas transmission systems
      • offshore pipelines
      • process piping systems

      Their high-integrity sealing design makes IX seal rings ideal for critical offshore applications.


      Why Use IX Seal Rings in Offshore Systems?

      IX seal rings provide:

      • superior leak prevention
      • excellent fatigue resistance
      • compact flange compatibility
      • reduced maintenance requirements
      • enhanced operational safety

      These advantages reduce:

      • offshore downtime
      • maintenance cost
      • environmental leakage risk

      Frequently Asked Questions

      What is a NORSOK IX seal ring gasket?

      It is a high-integrity metal seal ring used in compact flange systems according to NORSOK L-005.

      What is the purpose of IX seal rings?

      IX seal rings provide leak-tight metal-to-metal sealing for offshore and high-pressure piping systems.

      What materials are used for IX seal rings?

      Common materials include:

      • Inconel 625
      • Duplex stainless steel
      • Super Duplex
      • carbon steel

      What is the difference between IX seal ring and RTJ gasket?

      IX seal rings are used in compact flange systems, while RTJ gaskets are used in conventional RTJ flanges.

      Are IX seal rings suitable for subsea systems?

      Yes. IX seal rings are widely used in subsea oil & gas systems.

      Can IX seal rings meet NACE MR0175 requirements?

      Yes. NACE compliant IX seal rings can be supplied for sour service applications.


      Related Products

      Compact Flange Systems

      • Compact Weld Neck Flanges
      • Compact Blind Flanges
      • ISO 27509 Flanges

      Offshore Flanges

      • ASTM A694 F65 Flanges
      • ASTM A350 LF2 Flanges

      High Yield Pipe Fittings

      • ASTM A860 WPHY 65 Elbow
      • ASTM A860 WPHY 70 Tee

      Offshore Fasteners

      • ASTM A453 Grade 660 Stud Bolts
      • ASTM A193 B7M Stud Bolts

      Why Choose Our NORSOK IX Seal Ring Gaskets?

      We provide:

      • precision machined seal rings
      • offshore project experience
      • NORSOK compliant manufacturing
      • corrosion-resistant alloy materials
      • NACE compliant products
      • strict dimensional inspection
      • export seaworthy packing
      • worldwide delivery support

      Our NORSOK IX seal ring gaskets are manufactured according to international offshore standards for reliable high-integrity sealing performance.