Dual phase steel globe valve

双相钢截止阀 is a valve made of ferritic and austenitic duplex stainless steel (such as 2205, 2507, etc.), which combines high strength and excellent corrosion resistance, especially suitable for high corrosion conditions such as chloride ions. Its main characteristics are as follows:
1、 Core advantages
Mechanical properties
The yield strength reaches 400-550MPa, which is twice that of ordinary austenitic stainless steel.
High toughness and stress corrosion resistance significantly reduce the risk of failure in chloride environments.
Corrosion resistance
The resistance to pitting and crevice corrosion is superior to 316L austenitic steel, and it is suitable for scenarios such as seawater and chemical media.
Super duplex steel 2507 (PREN ≥ 40) is resistant to strong corrosive media such as high concentrations of chloride ions and hydrogen sulfide.
2、 Key points of design and process
Structural optimization
The duplex steel globe valve adopts a top guide or cage structure to ensure the coaxiality of the valve stem and seat (error ≤ 0.05mm).
The streamlined flow channel reduces the flow resistance coefficient (K value ≤ 5) and reduces energy consumption.
Sealing technology
Metal hard seal+soft seal composite: Welding with Stellite alloy ensures high temperature and high pressure sealing, with PTFE or corrugated pipe auxiliary sealing.
Double sealing design: V-shaped packing (flexible graphite) is heat-resistant, and the corrugated tube structure achieves zero leakage.
Manufacturing process
Welding requires strict control of heat input (≤ 1.5kJ/mm) to avoid high temperatures causing an imbalance in the two-phase ratio.
The machining accuracy of the sealing surface needs to reach Ra0.8 μ m or above to prevent residual corrosion of the medium.
3、 Application scenarios and selection
Recommended materials for scenes and precautions
Seawater desalination/sewage treatment 2205 (PREN ≥ 34) requires a built-in filter screen to prevent impurities from jamming
High corrosion chemical medium 2507 super duplex steel to avoid transporting mud like media
Toxic/flammable environment corrugated pipe sealing model such as J41F soft seal globe valve
Standard: Pressure bearing parts can be selected from American standard A995 castings (such as GR.4A/CD3MN) or A182 forgings (such as F53/S32750).
Operation tip: It is recommended to match electric actuators for frequent opening and closing situations, and accurate calculation of torque and stroke parameters is required.

截止阀