ACCELERATED LIFE TESTING

Pressurized Testing of Heat Exchangers

Touchstone Research installed systems on all corrosion cabinets (B 117, SWAAT, CASS, SO2) that allow us to pressurize complete heat exchanger assemblies (i.e. radiators, evaporators, condensers, etc.) to simulate use conditions while exposed to corrosive environments. Typically the systems use either compressed nitrogen or helium gas which is supplied through a regulator/manifold assembly from a high-pressure cylinder. Each test specimen is isolated from the others (up to 12 per cabinet) so leaks that develop from corrosion are easily detected. After the heat exchanger has failed it is re-pressurized to allow location of the actual failure site. This site, along with other typically corroded areas is examined metallographically to clearly understand the failure mechanism. This test has been used successfully with radiators (20 psi), evaporators (100+ psi) and condensers (400 ­ 600 psi). Using this method Touchstone has tested both the heat exchangers as individual parts and entire heat exchanger assemblies like the HVAC units for automobiles.

Index of Accelerated Life Testing