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Fusion™ 935

Explosive Decompression Resistant

SEALING SOLUTIONS

Greene, Tweed’s Fusion™ 935 is a fluorocarbon elastomer specifically designed for ED (explosive decompression) resistance in compressor components, valves and pumps in hydrocarbon refining, pipeline and oilfield applications. ED is a phenomenon that often occurs when high-pressure gas molecules migrate into an elastomer at a compressed state. When the pressure surrounding the elastomer is suddenly released, the compressed gas inside the elastomer tries to expand and exit the elastomer, thus causing ED. Most elastomers experience
severe blistering or cracking when the forces of these expanding gases overcome the strength of the surrounding material, but 935 provides superior ED resistant properties. Fusion™ 935 offers superior ED properties, broader chemical compatibility and an improved lower temperature operating window. For example, much better resistance to methanol, sour gas, hot water, steam and corrosion inhibitors than conventional fluorocarbon elastomers. In addition, its compression set delivers improved sealing and leak prevention
unmatched by the leading competitive material.

Features & Benefits

  • Provides reliable ED resistance at low temperatures down to -35ºF (-37ºC) so parts maintain sealing properties and equipment life is extended
  • Offers reliable ED resistance with compression set values that are much lower than existing material while preventing leakage and contamination of the product
  • Extends the life of refining, pipeline and oilfield equipment exposed to unanticipated process upsets resulting in pressure drops
  • Reduces maintenance cost
  • Increases mean time between failure

APPLICATIONS

  • Compressor components
  • Valves
  • Pumps
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AVAILABILITY

  • O-rings
  • G-T® rings
  • Custom-molded shapes
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FKM 935 has been successfully tested under the following conditions:

TEST RESULTS

Because of the relationship of pressure and volume in near ideal gases, ED damage is realized near the lower end of a decompression cycle. If the gases trapped in the elastomer are assumed to be ideal, the damage due to ED is highly dependent on absolute pressures rather than the pressure change.

Test Details
Test A

  • Standard NACE TM0192-98.
  • Single cycle, 24-hour pressure soak with near instantaneous (3 seconds) pressure drop.
  • Seals are placed in a pressure vessel and are unrestrained with pressure on all sides.
  • Results*: -214 O-rings: Internal 1,1 External 1,1 (2 samples).
  • Results*: -325 O-rings: Internal 1,1 External 1,1 (2 samples).

Test B
• Test based on Shell DODEP 02.01B.03.02 requirements.
• -214 O-rings.
• 3 cycles, consisting of a 48-hour hold at elevated pressure and
temperature. Each decompression is at a rate no less than
1000 psi/min. Entire fixture is maintained @ ambient pressure
for a minimum of 1 hour between cycles.
• Seals are constrained as a face seal with no back-up ring. Nominal
squeeze and gland fill are 17% and 77% respectively.
• Fluid media is approximately 30% CO2 (by volume), balance N2.
• Results*: Internal: 1,1 External: 1,1 (2 samples tested).

Test C

  • Test based on Shell DODEP 02.01B.03.02 requirements.
  • -214 O-rings. 5 cycles, consisting of a 48-hour hold at elevated pressure and temperature. Each decompression is at a rate no less than 1000 psi/min. Entire fixture is maintained @ ambient pressure for a minimum of 1 hour between cycles.
  • Seals are constrained as a face seal with no back-up ring. Nominal squeeze and gland fill are 17% and 77% respectively.
  • Fluid media is approximately 30% CO2 (by volume), balance CH4 (Methane).
  • Results*: Internal: 1,1,1 External: 1,1,2 (3 samples tested).

Test D

  • Test based on Shell DODEP 02.01B.03.02 requirements.
  • -214 O-rings.
  • 5 cycles, consisting of a 48-hour hold at elevated pressure and temperature. Each decompression is at a rate between 1000 – 1200 psi/min. Entire fixture is maintained @ ambient pressure for a minimum of 1 hour between cycles.
  • Fluid media is approximately 5% CO2 (by volume), balance N2.
  • Results*: Internal: 1,1,1 External: 1,1,1 (3 Samples tested).



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