HomeService by FluidEthylene (C₂H₄)
hydrocarbonC₂H₄CAS 74-85-1

Valves for Ethylene (C₂H₄) Service

Ethylene is the world's largest-volume petrochemical feedstock — produced by steam cracking of naphtha, ethane, or LPG, then used to manufacture polyethylene, PVC, ethylene oxide, styrene, and dozens of downstream chemicals. Ethylene is handled as a gas at ambient conditions and as a cryogenic liquid below −104°C. Major Indian ethylene producers include IPCL, Reliance Industries (Jamnagar), ONGC Petro additions (Dahej), and GAIL (Pata).

Pressure Range

Up to 40 bar (gas phase); near-atmospheric (cryogenic storage)

Temperature

−104°C (cryogenic liquid) to 50°C (gaseous pipeline)

Industries

Petrochemical ethylene cracker, Polyethylene plant, Ethylene oxide / glycol plant

INDICATIVE ONLY — Reference DisclaimerEthylene is a highly flammable gas with a wide flammability range. All equipment must comply with ATEX requirements, fire-safe standards, and applicable safety regulations. HAZOP review and quantitative risk assessment are mandatory for ethylene-handling facilities. Vajra Industrial Solutions accepts no liability for material selection decisions based on this guide.

Key Properties — Ethylene (C₂H₄)

  • Boiling point: −104°C (cryogenic liquid in storage and transport)
  • Gas at ambient conditions; highly flammable (LEL 2.7%, UEL 36%)
  • Wide flammability range — significant explosion risk
  • Operating pressure in crackers: up to 40 bar; storage: atmospheric (cryogenic)
  • Polymerisation inhibitor may be required to prevent fouling in heat exchange service

Material Compatibility — Ethylene (C₂H₄)

Ratings are indicative. Actual compatibility depends on concentration, temperature, velocity, and presence of contaminants. Always consult corrosion tables or a materials engineer.

MaterialRatingNotes
Carbon Steel (WCB/A105)GoodSuitable for gaseous ethylene above −29°C; not for cryogenic liquid.
A352 LCB (low-temp CS)GoodFor ethylene service down to −46°C.
SS 316 / CF8MExcellentSuitable across full temperature range including cryogenic ethylene storage at −104°C.
A350 LF2 (forged, low-temp)GoodFor forged valves in ethylene service to −46°C.
PTFE seatsGoodAcceptable for gaseous ethylene; cryogenic-grade PTFE for −104°C liquid service.

Recommended Valves

Trunnion Ball Valve (API 6D, fire-safe)

Mainline isolation in ethylene transfer and pipeline service — DBB, anti-static, fire-safe.

Cryogenic Ball Valve (A351 CF8M, extended stem, BS 6364)

Ethylene cryogenic storage and transfer at −104°C.

Gate Valve (API 600, fire-safe, ATEX)

Large-bore isolation on ethylene cracker and separation train.

Globe Valve (SS 316, with positioner)

Flow control on ethylene feed lines and recirculation.

Valves to Avoid

Standard CS valves in cryogenic ethylene service (brittle fracture risk below −29°C)

Copper alloy valves (ethylene can form explosive copper acetylide with trace acetylene impurity)

Non-fire-safe valves in any ethylene-carrying service

Elastomeric seated valves without ethylene compatibility verification

Special Considerations

Wide flammability range (2.7–36%) — explosion risk is greater than methane
Copper alloys must be avoided — trace acetylene in ethylene forms explosive copper acetylide
Cryogenic service requires BS 6364 type-tested valves and extended stems
ATEX Zone 1 classification for all electrical equipment in ethylene areas
Anti-static continuity essential for all quarter-turn valves

Applicable Standards

API 6D (pipeline)API 607 (fire-safe)BS 6364 (cryogenic)ATEX Zone 1 (electric actuators)NFPA 59A (LNG/cryogenic)

Shop Valves for Ethylene (C₂H₄) Service

Other Fluid Services

Need Valves for Ethylene (C₂H₄) Service?

Tell us your fluid, pressure, and temperature — we'll recommend the right valve, material, and standard.