Cavitation erosion resistance of sewer pipe materials

A cavitating high-pressure water-jet provided the means by which a range of materials (plastics, clay and concrete) were eroded. The measured erosion resistance was a proxy for an initially unknown combination of other properties: strength, fracture toughness, impact resistance, hardness, surface roughness, and limiting service temperature. To ascertain the cause of damage to sewers during high-pressure water-jetting, information about which material properties contributed to the measured erosion resistance under a standard high-pressure water-jetting test were found. The experimental work, and published literature, provided a database of physico-mechanical, physicochemical, thermal and tribological material properties each of which in turn were correlated with the measured jetting resistance. The properties best correlated with the jetting resistance were: maximum service temperature (R25 0.93), elastic modulus (R25 0.90), surface roughness (R25 0.89), density (R25 0.87), and thermal conductivity (R25 0.87). The correlation coefficient between jetting resistance and impact resistance (R25 0.56) lay just outside the top 10, suggesting that this was not an impact problem but a more complex combination of strength, roughness, and heat dissipation despite actual failures ultimately resulting from fracture (for which toughness was nevertheless also poorly correlated (R25 20.38)). Traditional mechanical wear, abrasion, and erosion resistance parameters (Taber abrasion (R25 20.24), limiting pressure-velocity (R25 20.57), and wear index (R25 20.23)) failed to correlate with the jetting resistance.