The excellent performance of the fully forged duplex stainless steel globe valve is determined by its material properties and the structural characteristics of the valve itself. Therefore, let's first understand the characteristics of duplex steel materials: the so-called "duplex stainless steel" is composed of approximately half ferrite and half austenite phases in its solid solution structure. Generally, a small amount of phase is not less than 30%. Due to the presence of ferrite and austenite in its structure, duplex stainless steel possesses the advantages of high strength, chloride stress corrosion resistance, and excellent toughness and weldability of ferritic stainless steel, as well as austenitic stainless steel.
Characteristics of fully forged duplex stainless steel globe valve
(1) The valve adopts integral forging processing or forging welding structure, and has passed non-destructive testing and solid solution treatment. The material structure is fine, and all surfaces are machined. The product has a beautiful appearance.
(2) Valve sealing pair spray welded with hard alloy. Materials such as nickel based welding powder, Stellite alloy, and tungsten carbide that can be sprayed and welded have a high hardness of HRC65 and excellent wear resistance, which improves the service life of valves.
(3) Due to the inherent characteristics of duplex steel materials, valves have strong resistance to hydrogen sulfide and chloride ion corrosion. (4) Fully considering the high-temperature deposition and scaling of coal water slurry medium. Requirements for the strength of ball valve stem due to the increase of opening and closing torque. Dual phase steel ball during design
The valve stem is made of 1740H precipitation hardened stainless steel. After precipitation hardening treatment, this material can achieve high strength and meet the practical requirements of valve use.
(5) The fully forged duplex stainless steel globe valve adopts a fixed ball form. The force exerted by the medium on the sealing pair is significantly reduced compared to the floating ball, resulting in a decrease in the opening and closing torque. The valve seat is designed as a closed structure, which can effectively prevent spring failure caused by sedimentation and scaling. The sealing ring is made of flexible graphite or plastic alloy. The material has excellent sealing performance and high temperature resistance (flexible graphite can reach 800 ℃, plastic alloy can reach 3000C), and the valve stem is made of precipitation hardened stainless steel.