Weidouli offers a comprehensive range of Duplex check valves for all types of applications and industries. As for dual plate check valves, they have JB/T 8937 & API 594 design, wafer type. As for the end connections: Flange RF, Wafer & Lug are all standard units.
The other available type of Weidouli Duplex check valves includes Duplex pressure seal check valve, Duplex nozzle check valve, Duplex single plate check valve, Duplex lift type check valve, Duplex swing check valve.
Duplex stainless steel is a steel that has half of the ferrite phase and half of the austenitic phase in its quenching structure, and generally, the minimum phase content must be up to 30%.
Excellent general corrosion resistance; superior to Stainless steel in most environments. Excellent resistance to localized corrosion including intergranular, pitting, and crevice corrosion; the CPT of Duplex steel is generally at least 35ºC. The grade is also resistant to chloride stress corrosion cracking (SCC) at temperatures of up to about 150ºC. Duplex steel will often perform well in environments that cause premature failure of austenitic grades. It has better resistance to seawater than Stainless steel.
Although Duplex steel has good high-temperature oxidation resistance, this grade - like other duplex stainless steels - suffers from embrittlement if held for even short times at temperatures above 300ºC. If embrittled, this can only be rectified by a full solution annealing treatment. Duplex stainless steels are almost never used above 300ºC.
A single check valve protects against the risk of backflow and back-siphonage contamination while a double check valve is typically two single check valves linked together. As the name of the two types of check valves suggested, a double check valve seems to function as two single check valves. In fact, a double check valve can provide safe backup if one of the single check valves fails for any reason. What is more, a double check valve even has screws on each side of a single check valve so that the valve port can be opened and cleaned, as debris can build up over time.
A duple check valve is made of a mixture of an austenitic phase and a ferrite phase. With strong corrosion resistance, a duple check valve can be used in various industrial applications such as pharmaceutical equipment, chemical equipment, seawater equipment, heat exchange, power generation, petrochemicals, gas processing, specialty chemicals, etc.