An ASTM A351 CF8M Control Valve is a fluid control device made from stainless steel SA-351 CF8M, which is a molybdenum-bearing modification of CF8 austenitic steel alloy. This material is the cast equivalent of wrought AISI 316 stainless steel, known for its enhanced general corrosion resistance and resistance to pitting by chlorides due to the presence of molybdenum. The control valve operates by adjusting the size of the flow passage based on signals from a controller, allowing precise regulation of flow rate and enabling control over process variables such as pressure, temperature, and liquid level.