Ni-Mo-Cr-W alloy (Hastelloy C-276)
Nickel-molybdenum-chromium-tungsten alloy. The material for the most aggressive media that stainless steel and other nickel alloys cannot withstand, such as wet chlorine, hypochlorite and hot contaminated mineral acids.
- Rp0.2 · MPa
- —
- Rm · MPa
- —
- TEMPERATURE
- −196 … +675 °C
- COST
Chemical composition
%. Ni balance.
Mechanical properties
The values in this section are being verified.
Service temperature
ASME B16.34 group 3.8: −218 … 675 °C.
This is the limit of the material itself. A valve's service temperature is usually set by the seal and seat materials; product pages give it for each seal option.
Media suitability GENERAL TREND
Emsal assessment. The final choice is made from corrosion tables, taking concentration, temperature, chloride content and flow velocity into account.
Strengths and weaknesses
Strengths
- Resistant even to wet chlorine and hypochlorite
- Very low carbon: no sensitization in welding
- Resistant in both oxidizing and reducing media
Weaknesses
- One of the most expensive valve materials
- Very difficult to machine
Manufacturing and use
- ECONOMY
- Very high.
- MANUFACTURING METHODS
- Fabrication from plate and bar · Casting (CW-12MW)
- TYPICAL VALVE PARTS
- Body · Disc · Stem
Source: ASTM B575 / B574. Values compiled and verified by Emsal Vana; for binding values, refer to the current edition of the standard and the material certificate.