Duplex Steel Valve Manufacturer in Europe

ValvesOnly Europe manufactures and supplies duplex and super duplex steel valves for corrosive, chloride rich, and high pressure applications. Our range includes ball, gate, globe, butterfly, check, plug valves, and basket strainers manufactured in UNS S31803, S32205, S32750, and S32760 grades for offshore, desalination, marine, chemical processing, and oil & gas industries.

What is a Duplex Steel Valve?

Duplex steel valves are devices that control the flow of liquid in a pipeline, and they are made of duplex stainless steel, which is an alloy composed of a mixed microstructure of austenite and ferrite. The duplex steel has superior properties over conventional austenitic stainless steel in terms of strength and chloride pitting and stress corrosion cracking.

Types of Duplex Steel Valve:

• Hastelloy C276/B3 Ball Valve – Uses a rotating bored ball for quarter turn shut off in corrosive service lines.
• Hastelloy C276/B3 Butterfly Valve – Uses a rotating disc in order to perform a quarter turn valve action.
• Hastelloy C276/B3 Check Valve – Enables one way flow and shuts automatically when there is an attempt of flow reversal in corrosive fluids.
• Hastelloy C276/B3 Globe Valve – Uses a disc and seat mechanism to throttle and regulate flow in corrosive process lines.
• Hastelloy C276/B3 Gate Valve – Uses a sliding gate for full open or full closed operation with minimal flow restriction.

Technical Specifications:

Selection Criteria for Duplex Steel Valve:

• Chloride content and risk of pitting or stress corrosion cracking
• Operating temperature and pressure at the valve location
• Requirement for shut-off, throttling, backflow prevention, or filtration
• Compatibility of seat and seal material with the process fluid
• Connection type matching upstream and downstream piping
• Mechanical strength requirement compared to standard austenitic grades

Benefits of Duplex steel valve:

• Corrosion Resistance – Can resist chlorides, oxidizing, and reducing acids based on type.
• Resistance To Pitting – The high amount of molybdenum prevents pitting corrosion in chloride containing mediums.
• High Temperature Resistance – Retains strength and corrosion resistance up to 450°C.
• Stress Corrosion Crack Resistance – Nickel based composition reduces cracking under tensile stress.
• Wide Chemical Compatibility – Handles both oxidizing and reducing acid environments.
• Long Service Life – Resists acid attack, extending valve life in corrosive duty.
• Weldability – Retains corrosion resistance in the heat affected zone after welding.
• Wide Operating Range – Performs from -40°C to 450°C without loss of integrity.

Installation Points for Duplex Steel Valve:

• Seawater intake and outfall lines
• Offshore platform process piping
• Desalination plant process lines
• Chemical injection and dosing systems
• Subsea and topside piping in corrosive environments
• Strainer installation ahead of pumps and control valves in chloride service

Materials of Construction:

Our duplex steel valves are manufactured in UNS S31803, S32205, and S32750 body construction, with internal trim in matching alloy or Stellite faced components for erosion resistance. Seat and sealing materials are selected from PTFE, reinforced PTFE, and graphite based on the operating temperature and process fluid.

Why Duplex Steel Valve?

• Manufactured in duplex and super duplex grades for chloride and corrosive service lines
• Available across gate, globe, butterfly, check, plug, basket strainer, and ball configurations
• Multiple end connections including flanged, butt weld, socket weld, and threaded
• Hydrostatic and pneumatic testing carried out prior to dispatch
• Material test certificates and traceability documentation provided on request
• Custom sizing, trim material, and pressure class configuration available for project specific requirements