AWWA C515 Reduced-Wall Ductile Iron Gate Valves

SJZ Metalsin supplies a series of AWWA C515 reduced-wall ductile iron gate valves for water supply service having a PH range of 6.5 to 8.5 and a temperature from 0.6°C to 52°C [33°F to 125°F]. They are resilient-seated gate valves with non-rising stems (NRS) or outside screw-and-yoke (OS&Y) rising stems. The AWWA C515 reduced-wall ductile iron gate valves may be furnished with the operation method such as handwheel, stem cap (wrench cap), gearbox, electrical or pneumatic actuators. The valve end connection types can be classified as flanged ends, mechanical-joint ends, and push-on joint ends.

AWWA C515 resilient seated gate valves made from ductile iron ASTM A536 Gr.65-45-12. Non-rising stem design, handwheel operated, fusion-bonded-epoxy (FBE) coating according to AWWA C550.

AWWA C515 resilient seated gate valves are designed with reduced-wall and both its body and bonnet shall be made from cast ductile iron. AWWA C515 gate valves are designed with reduced-wall thickness due to the enhanced properties of ductile iron compared to the gray cast iron used in AWWA C509 gate valves. Ductile iron offers significantly higher tensile strength and yield strength, along with superior ductility, allowing for thinner walls while maintaining structural integrity and performance. This reduced-wall design is achieved through advanced engineering methods, such as finite element analysis, which ensures that the valves can withstand operational stresses despite having thinner walls. Additionally, ductile iron’s resilience to fracture under stress and its ability to yield without breaking enhance the valve’s durability. The reduced-wall thickness results in lighter valves, simplifying transportation, handling and installation. Moreover, the use of fusion-bonded epoxy (FBE) coatings further protects these valves from corrosion, ensuring their longevity in various environments.

AWWA C515 rising stem resilient seated gate valves, ductile iron, flanged ends.

The body and bonnet of a AWWA C515 reduced-wall gate valve shall be made from cast ductile iron. The microstructure of ductile iron is characterized by the presence of spheroidal graphite nodules embedded within a matrix of ferrite and/or pearlite, which distinguishes it from the flake graphite structure found in gray cast iron. This nodular graphite formation is achieved through the addition of magnesium or cerium to the molten iron, which modifies the graphite’s shape. The spheroidal nodules minimize stress concentration points, thereby enhancing the material’s strength and ductility. This unique microstructure provides ductile iron with a combination of high tensile strength, good yield strength, and excellent elongation, making it an ideal material for applications requiring robust mechanical properties and resistance to fracture. AWWA C515 reduced-wall gate valves are typically made from ductile irons of ASTM A536 Grade 65-45-12 or ASTM A395 Grade 65-45-15, both of which feature the minimum 65000 tensile strength and 45000 yield strength. The difference between these two ductile iron grades lies in their respective minimum elongation values: one is 12%, while the other is 15%.