Tribological properties of the seat insert - valve - guide assembly for valve driven magnetoelectrically

The researches have been carried out, where the object has been the set of two friction couples: valve stem - valve guide and valve seat - seat insert. The camless driven valve has been common for each of such cases. The analyzed valve has been driven by magnetoelectrical drive. The speciał research stand has been elaborated and its scheme has been presented in the article. It has been measured the valve lift and valve acceleration, the impact force, the friction force, temperature values for valve guide and for seat insert, sound level during impacting on the stand. The aim of researches has been to determine the dynamic parameters, the friction force between valve stem and valve guide, the impact force for valve impacting seat insert vs. frequency and valve lift. The analyzed valves have mated with seat inserts and valve guides made of cast iron, in oil absence. The valves have been made of TiAl6Zr4Sn2Mo2 alloy. The researched friction couples have operated in temperature equal 293 K. The increase of frequency has resulted in small changes for values of lift and in greater changes of acceleration, during valve impact into its seat insert. The greatest values of impact force and acceleration have been for the small, middle and high values of valve lift, either. The ratio of impact force and valve acceleration has changed in thin bands. The friction force has decreased slightly with frequency increase and has decreased with valve lift increase. The sound level has increased with the frequency increase, and has not been dependent upon valve lift.