Stainless steel valve elements refer to valve parts made of stainless steel. Stainless steel valves are widely used in chemical, petrochemical, petroleum, papermaking, mining, electric power, liquefied gas, food, pharmaceutical, water supply and drainage, municipal, mechanical equipment, electronic industry, urban construction and other fields. The valve is a control component in the pipeline fluid conveying system, which is used to change the passage section and flow direction of the medium, and has functions such as diversion, cutoff, regulation, throttling, check, shunt or overflow pressure relief. . Valves for fluid control range from the simplest globe valve to the most complex automated systems. Stainless steel valves can be used to control the flow of water, steam, oil, gas, mud, various corrosive media,

Stainless steel casting of valve components

Stainless steel is characterized by corrosion resistance, toughness and weldability. The valve parts made of stainless steel are durable and not easy to rust. In addition, stainless steel is affordable, so the main valve components are mainly produced by stainless steel investment casting.

Stainless Steel Types for Valve Castings:
304 stainless steel: 18% chromium and 8% nickel, commonly known as 18-8 stainless steel. This stainless steel contains nickel to create valve elements with good corrosion resistance
410 stainless steel: 13% chromium, less than 0.15% carbon and a small amount of other elements. But it does not contain nickel, and its corrosion resistance is relatively poor.
430 stainless steel: 16%~18% chromium, low carbon content, no nickel element, low price.
Hardened stainless steel: In addition to chromium and nickel, it also contains hardening elements such as copper, aluminum, and titanium, which can harden the material and increase the strength of valve components.
Duplex Stainless Steel: A typical grade is 2205, which is 22% chromium and 5% nickel.

Main valve components of stainless steel castings:
Body: The main valve component that connects directly to the pipeline and controls the flow of the medium.
 valve bonnet: the key component of butterfly valve.
Bonnet: The valve part that is connected to the valve body and forms a pressure chamber with the valve body.
Valve Handwheel: A common valve component used to override control systems and manually operate valves.

Stainless steel casting process for valve components
Pattern Creation - Wax molds are usually injection molded into aluminum molds and formed as a whole. Ceramic cores can be used to form any internal feature on the pattern. Some of these patterns are connected to a central wax gating system (runners, runners and risers) to form tree-like assemblies. The gating system forms the channels through which the molten metal will flow into the mold cavity.
Mold Creation - This "pattern tree" is dipped into a slurry of finely fused silica, ceramic particles, coated with coarser particles, and dried to form a ceramic shell around the pattern and gating system. Repeat this process until the shell is thick enough to withstand the molten metal it will encounter. The shell is then placed in an autoclave and the wax is melted, leaving a hollow ceramic shell as a one-piece mold, hence the name "lost wax" casting.
Pouring - The mold is preheated in a furnace to approximately 1800°F – 2000°F, and molten metal is poured from a ladle into the mold's gating system, filling the mold cavity. Pouring is usually done manually under gravity, but other methods such as vacuum or pressure are sometimes used.
Cooling - After the mold is filled, the molten metal is allowed to cool and solidify into the shape of the final casting. The cooling time depends on the thickness of the part, the thickness of the mold and the material used.
Casting Removal - After the molten metal cools, the mold can be broken and the casting removed. Ceramic molds are usually removed using pneumatic vibrating water jets, but several other methods exist. Once removed, the part is separated from the gating system by sawing or cold breaking (using liquid nitrogen) in some cases.
Finishing - Typically, finishing operations such as sanding or sandblasting are used to smooth the part at the gate. Heat treatment is also sometimes used to harden the final part.