The requirement is less than 2.5% rust after completion.
The valves were placed in ammonia for 14 days at 25°C (with pressure of approximately 4 bar) and then in salt mist for 96 hours (35°C and 5% saline).
After exposure of ammonia and salt mist the valves were inspected carefully. The test results showed little or no rust after ammonia exposure, but severe rust attack after exposure to salt mist.
Standard sample before testing chamber.
After exposure of ammonia for 14 days.
After 96 hours in salt mist.