Duplex & Super Duplex Steel Valves

VALVA is a leading specialist in Duplex and Super Duplex stainless steel valves. By combining the best properties of both Ferritic and Austenitic structures, these valves offer a unique “dual-phase” performance: the high strength of ferrite combined with the superior corrosion resistance of austenite.

The Duplex Advantage: Strength Meets Durability

Why choose Duplex steel for your flow control systems?

Double the Strength: The yield strength of Duplex steel is more than twice that of ordinary 316L stainless steel. This allows for wall thickness reductions of 30-50%, significantly lowering the overall project cost.
Superior Stress Corrosion Resistance: Even the most basic Duplex grades outperform standard austenitic steels in resisting stress corrosion cracking (SCC), especially in high-chloride and ammonia-rich environments.
Exceptional Localized Corrosion Protection: With higher resistance to pitting, crevice corrosion, and fatigue, our 2205 (4A) and 2507 (5A) series are engineered for the harshest industrial cycles.
Thermal Compatibility: The linear expansion coefficient is close to that of carbon steel, making it the ideal choice for composite plates, linings, and connections to carbon steel piping.

Engineered for High-Energy Impact

Whether under static or dynamic loads, Duplex steel has a higher energy absorption capacity than standard stainless steel. This makes VALVA Duplex valves safer and more reliable in structural applications where sudden impacts or pressure surges may occur.

Comprehensive Material Grades

We provide a full range of Duplex and Super Duplex alloys to meet international standards:

Series	Common Cast Grades	ASTM/UNS Designations
Standard Duplex	4A (CD3MN), 1A, 2A, 3A	F51, F60, S31803
Super Duplex	5A (CE3MN), 6A (CD3MWCuN)	F53, F55, S32750, S32760
Specialized Grades	CD4MCu, CD6MN, CE8MN	1B, 1C