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Weather-Resistant EPDM Seals for Offshore Topside Equipment

Safety is paramount in offshore drilling, which is why many critical hydraulic systems utilize Fire-Resistant Hydraulic Fluids (Phosphate Esters) like Skydrol®, Hyjet®, or Fyrquel®. Standard oilfield seals (NBR, HNBR, FKM) will swell uncontrollably and fail instantly in these fluids. Our Specialty EPDM O-Rings are chemically engineered for full compatibility with Phosphate Ester fluids, ensuring the reliability of Motion Compensators, Tensioners, and BOP Control systems where fire safety cannot be compromised.

Technical Specifications

  • Pressure Rating: normal
  • Temperature Range: -65°F to +350°F (+400°F Intermittent)
  • Material: EPDM (Ethylene Propylene Diene Monomer)

Applications

  • Downhole Tools, Used in MWD/LWD tools, packers, and bridge plugs where temperatures exceed 300°F and chemical resistance to drilling muds is required.
  • Chemical Injection, Seals for pumps and valves injecting corrosion inhibitors, methanol, or biocides (Requires Viton® GF).
  • Subsea Equipment, Christmas trees, manifolds, and risers requiring long service life and cold resistance (Requires Viton® GLT).
  • Gas Processing & Transmission, Compressors, dehydration units, and gas valves handling high-pressure gas, requiring RGD/AED resistance.
  • Refineries, Mechanical seals, flange gaskets, and heat exchanger gaskets handling hot crude oil, fuels, and hydrocarbon solvents.
  • Wellhead Control, Hydraulic control panels and actuator seals.

EPDM O-Rings for Phosphate Ester Hydraulic Fluids (Skydrol Compatible)

Technical Deep Dive: The Chemistry of Fire Resistance

The “Polar” Opposite

Hydraulic sealing follows the rule “Like Dissolves Like.”

  • The Problem: Phosphate Ester fluids are “Polar” fluids. NBR and FKM are also polar materials. If you mix them, the seal absorbs the fluid like a sponge (swelling 100-200%).

  • The Solution: EPDM is a “Non-Polar” material. It is chemically inert to Phosphate Esters, maintaining its volume, hardness, and tensile strength even under high-pressure dynamic cycling.

Critical Applications: Motion Compensation

Drillships and Semi-Submersibles rely on active heave compensation to keep the drill bit steady while the ship moves with the waves.

  • Heave Compensators: Dynamic piston seals and static O-rings in the main hydraulic cylinders utilizing fire-resistant fluid.

  • Riser Tensioners: Seals ensuring the constant tension of the marine riser system.

  • BOP Control Systems: For systems using water-glycol or synthetic fire-resistant fluids.

Fluid Compatibility List

Our EPDM O-Rings are Approved for use with:

  • Phosphate Esters: Skydrol® (LD-4, 500B), Hyjet®, Fyrquel®.

  • Water-Glycol Fluids: HFC Fluids.

  • Brake Fluids: DOT 3, DOT 4, DOT 5.1.

❌ DANGER: Do NOT use with Mineral Hydraulic Oil (Hlp), Grease, or Diesel.

Identification & Safety

To prevent catastrophic mixing of seals on the rig floor (mistaking EPDM for NBR), we offer visual identification options:

  • Color Coding: Available with Purple or White dots/stripes.

  • Packaging: Clearly labeled “EPDM – PHOSPHATE ESTER ONLY”.

Specifications

Property Specification
Material Peroxide-Cured EPDM
Hardness 80 or 90 Shore A (For High Pressure)
Pressure Rating Up to 5,000 PSI (With Backup Rings)
Temp Range -65°F to +300°F