Which material is recommended for piping ammonia refrigerant R-717?

Which material is recommended for piping ammonia refrigerant R-717?

• A. Copper
• B. Carbon steel
• C. PVC
• D. Aluminum

Answer: (B)

Ammonia (R-717) piping requires materials that won’t corrode in contact with NH3. Ammonia is highly aggressive toward nonferrous metals, so copper, aluminum, and their alloys are avoided in piping because they can suffer corrosion and leaks over time. Carbon steel is a standard, cost-effective choice that resists ammonia under typical refrigeration conditions and handles the pressures and temperatures involved in industrial systems. PVC can't withstand the pressures or the chemical environment of ammonia service, and aluminum is susceptible to ammonia-related attack. So carbon steel is the best material for R-717 piping.

Ammonia (R-717) piping requires materials that won’t corrode in contact with NH3. Ammonia is highly aggressive toward nonferrous metals, so copper, aluminum, and their alloys are avoided in piping because they can suffer corrosion and leaks over time. Carbon steel is a standard, cost-effective choice that resists ammonia under typical refrigeration conditions and handles the pressures and temperatures involved in industrial systems. PVC can't withstand the pressures or the chemical environment of ammonia service, and aluminum is susceptible to ammonia-related attack. So carbon steel is the best material for R-717 piping.