eli5: If water is non-compressible, then why not use it in hydraulic machines instead of hydraulic oil?

Question

eli5: If water is non-compressible, then why not use it in hydraulic machines instead of hydraulic oil?

In: 1817

Answer 1

The main reason water is unsuitable for modern hydraluic applications is because modern systems run at high pressures and high temperatures. Under the conditions most modern hydraulics run, water would cavitate (convert to a gas). Once there is gas in a hydraulic system it can not function.