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Salt Spray Temperature and Pressure

If operating outside the pressure requirements ( ASTM B117) for the tower and air for atomization, is there an equation to calculate the appropriate temperature to use?

Thomas Brown
plating shop employee - Colorado Springs
May 23, 2008

Why are you salt spray testing? You can not operate the system out of specifications and certify it to passing salt spray B117 testing.

James Watts
- Navarre, Florida
May 28, 2008

ASTM B117 states "If the tower is run outside of these suggested temperature and pressure ranges (Table 2) to achieve proper collection rates other means of verifying proper corrosion rates should be investigated..." At 12 PSI the suggested temperature is 114 °F. The method used to calculate this temperature probably involves the enthalpy of vaporization of water. I believe the temperature of the vaporized water will be lower and I suspect the target temperature is 95°F for the vaporized water.

Thomas Brown
plating shop - Colorado Springs, Colorado
May 29, 2008

Semantics, but it is atomized solution, not vaporized, a big difference.

James Watts
- Navarre, Florida
May 30, 2008

Thanks for the advice. I was able to get the proper collection rate at the correct PSI and temperature. I think the temperature of the bubble chamber and pressure will effect droplet size.

Thomas Brown
- Colorado Springs, CO
July 14, 2008