To achieve such high reliability, please use the best brands, either Rexroth in Germany or Viggs in America. Suction 100 times is not a problem, and many valves can do it. The oil temperature and cleanliness of hydraulic oil must be strictly controlled to prevent the valve core from being stuck.
For this highly reliable system, I suggest to use the stop valve, that is, the setting valve, which is more reliable than the slide valve and the valve core is not easily stuck.