Study on the contamination wear failure of hydraulic valve and the influencing factors

The contamination wear failure of hydraulic valve is one of the common faults of tracked vehicle. The contamination wear process of hydraulic valve is analyzed from a micro point of view. A model of contamination wear process is established using the theory of three-body abrasion and oil analysis, and then the model is verified by an example. At last, the influencing factors of the hydraulic valve contamination wear are analyzed. Results show that the model is reliable. A lower hardness difference between the spool and the body, a shorter spool contact length and a smaller spool diameter lead to a longer contamination wear life; a higher oil contamination level, a larger proportion of big particles, a higher operating pressure and a higher operating temperature cause a shorter contamination life.