Cavitation cautions

Caution When a pump completely loses flow, it runs smooth, steady, and quiet. Its discharge pressure is stable. Its discharge flow is also stable and steady—a steady zero. This is not cavitation. The pump impeller is just spinning, to no particular purpose in the empty impeller case.)... 

The GRP generally showed higher cavitation erosion rates than 6 Mo-steel, titanium or high-density polyethylene. Damage incubation times for GRP ranged from a few minutes to almost 2h. No detectable erosion loss was recorded for the other three materials after more than 20 h. However, the author cautions that there are no scaling methods available to relate the high intensity accelerated cavitation test results to in-service performance. 

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