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The present study aims to identify nanoparticles amenable to the decrease of erosion and corrosion in various working states.  In this regard it is argued that the negative effects on erosion and corrosion imposed due to the presence of nanoparticles are reflected from the nanoparticles shape. In this situation, WS2 featured by possessing an almost round shape is suitable for decreasing the erosion and corrosion which is undergone the present experiment. The presented experiments are in different rotational speeds as well as different working pressures. As a gist, WS2/H-100 nanofluids are suitable to decrease the surface erosion associated with ST420 and ST316 up to about 14% in 5% volumetric fraction, in the working pressures ranging from 2-8 Kg-Force and in the rotational speeds ranging from 19-220rpm. This was whilst, for the above range and with respect to Mo40 the decreasing effect was identified to be about 3%. For the corrosion, the use of nanoparticles with 5% volumetric fraction was suitable to decrease the corrosion effect of the working allows ST420 and ST316 up to 7% compared to the pure base fluid (oil). However, in the same conditions it was recorded a decrease of about 2% with respect to Mo40.