implosion

I use this word quite often when trying to explain taht my condensate pump is a hallow body with no moving part or impeller and hence not damage by pump cavitation. Pump cavitation occurs due high temperature condensate return water >80 C. Above 80 C the condensate converts to flash steam which enters the impeller slots and "IMPLODES" (someting like bursting out explaining with both hands for the client to understand what is imploding ....then forgetting for the rest of his life what is exploding ) resulting in pump cavitation ....and blah....blah