5 products in this product line

Valtec welcomes you to explore our cutting-edge Seawater Valves (Duplex Stainless Steel), specifically engineered for seawater environments, this variant of stainless steel seamlessly combines cost-effectiveness with unparalleled corrosion resistance. Tailored to withstand harsh conditions, our super duplex steel valves ensure the necessary strength and durability for an extended service life.

Explore a diverse range of Duplex Stainless Valves for various applications: 3-way ball valves, 2-pc ball valves, butterfly valves, gate valves, swing check valves, and more. Contact us to discuss your specific Seawater valve requirements today!

For detailed technical specifications, contact us at valtec@valtec.com.tw or fill out the contact form on our website.

Valtec_Super Duplex 5A 2PC Ball Valve


  • Seawater
  • Sulfuric acid
  • Steam
  • Pulp water
  • Pulp liquors at 220°F (104°C)
  • Potable water
  • Offshore oil and gas platforms
  • Offloading vessels
  • Floating storage
  • Fatty acids
  • Desalination plants
  • Concentrate brine
  • Chlorides used in flue-gas cleaning

Material Table

Welcome to view our complete material table here for international standards of DIN EN, ASTM, JIS, and UNS.

  • Duplex Stainless Steel
  • Super Duplex Stainless Steel
  • Duplex 1B: ASTM A890/A955 Grade 1B (CD4MCuN)
  • Duplex 1C: ASTM A890 Grade 1C (CD3MCuN)
  • Duplex 2A: ASTM A955 Grade 2A (CE8MN)
  • Duplex 3A: ASTM A890 Grade 3A (CD6MN)
  • Duplex 4A: ASTM A890/A995 Grade 4A (CD3MN)
  • Super Duplex 5A: ASTM A890/A955 Grade 5A (CE3MN)
  • Super Duplex 6A: ASTM A890/A955 Grade 6A (CD3MWCuN)
  • Super Duplex 329

Standards / Corrosion Tests

A meticulous valve assembly process is employed to eradicate hydrocarbon oil, grease, metal chips, and other ignition hazards that may arise from suboptimal deburring processes or contaminants in the shop environment. The cleaning and inspection protocols for valve components used in oxygen service are seamlessly extended to cryogenic service, adhering to all relevant international standards and corporate specifications.

All Valtec valves undergo testing in accordance with EN 12266-1, achieving leakage rate A and Bubble Tight Shutoff, with the option for testing according to ISO 5208 or API 598 upon request.

Our Seawater Valves series adheres to stringent standards and testing procedures. Notably, upon request, we follow the industry-respected ASTM G48 standard. This ensures that our valves undergo thorough corrosion resistance testing, meeting the highest benchmarks for performance in challenging seawater environments. By incorporating ASTM G48 testing, we assure our customers of the superior durability and functionality of our seawater valves with duplex, aligning with our commitment to delivering high-quality products that excel in demanding conditions.