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Supagraf® H2

Supagraf H2 is a high performance, unique combination, valve stem packing set designed for hydrogen service.

  • CO2
  • Fugitive emissions
  • Hydrogen
  • Valves

This packing solution incorporates Supagraf Premier, one of James Walker’s top-of-the-range fugitive emission control packings that has a long track record of exceptional performance in valves handling hydrocarbon liquid fuels and gases, lubricating oils or processing chemicals including hydrogen and CO2.

The performance of Supagraf Premier graphite packing rings are then enhanced by the use of precision machined carbon rings, inserted at the top and bottom of the stuffing box set and used as intermediary rings.

This product has been third party tested and is validated by James Walker for use in hydrogen service, including liquid hydrogen at cryogenic temperatures.

Supagraf H2 is designed specifically for the harsh operating conditions of all types of valves in hydrogen service, where exceptional tightness, safety and extended dynamic sealing performance is required, including cryogenic valves handling liquid hydrogen.

The product is also compatible with different blends of hydrogen and other liquid or gaseous media including CO2 as well as hydrocarbons or chemicals.

Valve stem duties

  • Maximum operating temperature in oxidising conditions: +450°C (+842°F)
  • Minimum Operating Temperature: down to cryogenic -253°C (-423°F)
  • Maximum System Pressure (Standard): 69 MPa/690 bar (10000 psi)

Contact us for advice where operating conditions are outside these limits.

Supagraf H2 combination packing set has been 3rd party tested and certified for hydrogen service. The test regime has been adapted from ISO 15848-1 standard and modified with the use of 99% hydrogen test media as opposed to ISO 15848-1 specified helium gas. The product has been tested at room temperature and to CO1 endurance class reaching class BH* leakage performance (with no adjustment).

The product has also been tested according to ISO 15848-1 standard (with helium test media) in configuration of Supagraf Premier graphite rings with single bottom stuffing box machined carbon ring, achieving class BH tightness at CO1 endurance class and temperature range from -196°C [-321°F] up to +400°C [752°F] (with no adjustment).

In addition, the stand-alone Supagraf Premier packing set has been tested and certified to:

  • ISO 15848-1 Class AH (fugitive emissions): Certified by ITIS BV at 69 MPa (static) with a five-ring set in a BSM valve. Emission level at 69 MPa/690 bar (10,000 psi) was ≤5 ppmV
  • API 622: average emission level of 10.5 ppmV, with a maximum of 37 ppmV over five thermal cycles and 1510 mechanical cycles
  • TA Luft Rev 07.2002 requirements/VDI 2440
  • Shell specification SPE 77/312 Class A, Rev 16.10.2002
  • Shell specification SPE 77/312 Rev 06.2007: Class B rating with 47.4 MPa/474 bar (6875 psi) helium in Class 2500 valve
  • API 607 Edition 4 Fire Safety
  • Base graphite material complies to Shell MESC SPE 85/204.

*Note: BH volumetric leak rate used for Hydrogen gas.

Compatible with media in the range of pH 0-14 excluding strong oxidising agents. The product has negligible volatile content.

As preformed graphite rings with a single split combined with precision machined carbon rings supplied endless or split in two matched halves with cut of 45 degrees. Product made to order to suit application requirements.

Related Downloads

Supagraf H2 datasheet

English pdf (350 KB) Download

Supagraf H2 fitting guide

English pdf (650 KB) Download

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