Mills [5,6] did extensive studies o

Mills [5,6] did extensive studies on bend erosion in pneumatic conveying systems,including testing the effects of particle con-centration. In his studies a term of particle ‘‘suspension density’’ (mass of particles per unit volume of gas flow) was used in the erosion measurements. The results obtained showed that the total mass lost from an entire bend, after conveying a fixed quantity of material, decreased when the suspension density of particles in the bend was increased, similarly to the other studies cited. He also explained this as being due to the likelihood of inter-particulate collisions increasing as the suspension density was increased. During the collisions particles would lose a part of their kinetic energy and thus have less energy available in the impact with the surface ,thus reducing the erosion because particle velocity is the leading variable in erosion(widely established by many studies).